Graphic symbols in electrical engineering. Symbol in electrical diagrams

Content:

In order to correctly read and understand what a particular diagram or drawing related to electricity means, you need to know how the icons and symbols depicted on them are deciphered. A large amount of information is contained in the letter designations of elements in electrical circuits, defined by various regulatory documents. All of them are displayed in Latin characters in the form of one or two letters.

One-letter symbolism of elements

Letter codes corresponding to individual types of elements most widely used in electrical circuits are combined into groups designated by one symbol. Letter designations correspond to GOST 2.710-81. For example, the letter “A” refers to the “Device” group, consisting of lasers, amplifiers, remote control devices and others.

The group denoted by the symbol “B” is deciphered in the same way. It consists of devices that convert non-electrical quantities into electrical ones, which does not include generators and power supplies. This group is complemented by analogue or multi-digit converters, as well as sensors for indications or measurements. The components themselves included in the group are represented by microphones, loudspeakers, sound pickups, ionizing radiation detectors, thermoelectric sensitive elements, etc.

All letter designations corresponding to the most common elements are combined into a special table for ease of use:

The first letter character required to be reflected in the marking	Group of main types of elements and devices	Elements that make up the group (the most typical examples)
	Devices	Lasers, masers, remote control devices, amplifiers.
	Equipment for converting non-electrical quantities into electrical ones (without generators and power supplies), analogue and multi-charge converters, sensors for indications or measurements	Microphones, loudspeakers, sound pickups, ionizing radiation detectors, sensitive thermoelectric elements.
	Capacitors
	Microassemblies, integrated circuits	Digital and analog integrated circuits, memory and delay devices, logic elements.
	Miscellaneous elements	Various types of lighting devices and heating elements.
	Designation of the fuse on the diagram, arresters, protective devices	Fuses, arresters, discrete current and voltage protection elements.
	Power supplies, generators, crystal oscillators	Rechargeable batteries, power supplies on an electrochemical and electrothermal basis.
	Signal and indication devices	Indicators, light and sound signaling devices
	Contactors, relays, starters	Voltage and current relays, time relays, electrothermal relays, magnetic starters, contactors.
	Chokes, inductors	Chokes in fluorescent lighting.
	Engines	DC and AC motors.
	Measuring instruments and equipment	Counters, clocks, indicating, recording and measuring instruments.
		Power circuit breakers, short circuiters, disconnectors.
	Resistors
Pulse counters
Frequency meters
Active energy meters
Reactive energy meters

Recording devices
Action time meters, clocks
Voltmeters
Wattmeters
	Switches and disconnectors in power circuits	Circuit breakers
		Short circuits
		Disconnectors
	Resistors	Thermistors
		Potentiometers
		Measuring shunts
		Varistors
	Switching devices in measurement, control and signaling circuits	Switches and Switches
		Push-button switches
		Automatic switches
		Switches triggered by various factors: From level
		From pressure
		From position (travel)
		From rotation speed
		From temperature
	Transformers, autotransformers	Current transformers
		Electromagnetic stabilizers
		Voltage transformers
	Communication devices, converters of non-electrical quantities into electrical ones	Modulators
		Demodulators
		Discriminators
		Frequency generators, inverters, frequency converters
	Semiconductor and electrovacuum devices	Diodes, zener diodes
		Electrovacuum devices
		Transistors
		Thyristors
	Antennas, lines and microwave elements	Couplers
		Short circuits

		Transformers, phase shifters
		Attenuators

	Contact connections	Sliding contacts, current collectors


		Separable connections
		High Frequency Connectors
	Mechanical devices with electromagnetic drive	Electromagnets
		Brakes with electromagnetic drives
		Clutches with electromagnetic drives
		Electromagnetic cartridges or plates
	Limiters, terminal devices, filters	Limiters
	Limiters, terminal devices, filters	Quartz filters

In addition, GOST 2.710-81 defines special symbols to designate each element.

Conventional graphic symbols of electronic components in circuits

STATE STANDARD OF THE USSR UNION

UNIFIED SYSTEM OF DESIGN DOCUMENTATION

CONDITIONAL GRAPHIC DESIGNATIONS IN SCHEMES.
ELEMENTS OF DIGITAL EQUIPMENT

GOST 2.743-91

GOSSTANDARD OF RUSSIA

Moscow – 1992

STATE STANDARD OF THE USSR UNION

one system design documentation

CONDITIONAL GRAPHIC DESIGNATIONS IN SCHEMES. ELEMENTS OF DIGITAL EQUIPMENT

Unified system of design documentation.
Graphical symbols in diagrams.
Elements of digital technology

GOST
2.743-91

Date of introduction 01.01.93

This standard establishes general rules for the construction of conventional graphic symbols (GID) of elements of digital technology in circuits performed manually or using computer printing and graphic output devices in all industries.

1. GENERAL PROVISIONS

1.1. An element of digital technology (hereinafter referred to as an element) is a digital or microprocessor chip, its element or component; digital microassembly, its element or component. Definitions of digital and microprocessor microcircuits, their elements and components - according to GOST 17021, definitions of a digital microassembly, its element or component - according to GOST 26975. Note. Elements of digital technology conventionally include elements that are not intended for converting and processing signals that change according to the law of a discrete function, but are used in logical circuits, for example, a capacitor, generator, etc. 1.2. When constructing the UGO, the symbols “0” and “1” are used to identify two logical states “logical 0” and “logical 1” (Appendix 1).

2. RULES FOR CONSTRUCTING UGO ELEMENTS

2.1. General rules for constructing a UGO

2.1.1. The UGO of the element has the shape of a rectangle, to which the lead lines are connected. The UGO of an element can contain three fields: the main one and two additional ones, which are located to the left and to the right of the main one (Fig. 1).

Note. In addition to the main and additional fields, the UGO element may also contain the circuit of a common control unit and the circuit of a common output element (Appendix 2). 2.1.2. In the first line of the main field of the UGO, the designation of the function performed by the element is placed. The subsequent lines of the main field contain information in accordance with GOST 2.708. Note. It is allowed to place information in the main field from the first position of the line, if this does not lead to ambiguity of understanding. Additional fields contain information about the purpose of the outputs (terminal labels, indicators). It is allowed to place indicators on the output lines on the contour of the UGO, as well as between the output line and circuit UGO.2.1.3. The UGO can consist only of the main field (Table 1, item 1) or of the main field and one additional one, which is located to the right (Table 1, item 2) or to the left (Table 1, item 3) of the main one, as well as from the main field and two additional ones (Table 1, clause 4). Additional fields are allowed to be divided into zones, which are separated by a horizontal line. The main and additional fields may not be separated by a line. In this case, the distance between alphabetic, numeric or alphanumeric designations placed in the main and additional fields is determined by the unambiguous understanding of each designation, and for designations placed on one line, there must be at least two letters (numbers, signs) with which these are made designations.

Table 1

Name	Designation
1. UGO containing only the main field
2. UGO containing the main field and one (right) additional field
3. UGO containing the main field and one (left) additional field
4. UGO, containing a main field and two additional ones, divided into zones. The number of zones is not limited.

Notes: 1. The signs “*” indicate the functions and pin labels of the elements. 2. It is allowed that elements depicted in a combined manner are separated graphically by communication lines, and the distance between the ends of the contour lines of the UGO and the communication lines must be at least 1 mm (Fig. 2).

2.1.4. The element pins are divided into inputs, outputs, bidirectional pins and non-carrying pins. logical information.Element inputs are shown on the left side of the UGO, outputs - on the right side of the UGO. Bidirectional conclusions and conclusions that do not carry logical information are depicted on the right or left side of the UGO.2.1.5. When connecting lead lines to the UGO contour, it is not allowed to: draw them at the level of the sides of the rectangle; put arrows on them near the UGO contour indicating the direction of the information. 2.1.6. Another orientation of the UGO is allowed, in which the inputs are located at the top and the outputs at the bottom (Fig. 3).

Note. In UGO orientations, when the inputs are on the right or bottom, and the outputs are on the left or top, it is necessary to put arrows on the output (communication) lines indicating the direction of information propagation, and the designation of the element’s function must correspond to that shown in the drawing. 4.

2.1.7. The dimensions of the UGO are determined by: by height: the number of lead lines; the number of intervals; the number of lines of information in the main and additional fields, font size; by width: the presence of additional fields; the number of characters placed in one line inside the UGO (including spaces), font size . 2.1.8. The ratios of the sizes of function designations, labels and pin indicators in the UGO, as well as the distances between the lead lines must correspond to those given in Appendix 5. The minimum step size of the modular grid M is selected based on the requirements of microfilming (GOST 13.1.002). 2.1.9. Inscriptions inside the UGO are made in the main font in accordance with GOST 2.304. When performing UGO using computer output devices, the fonts available in them are used.

2.2. Designations of element functions

2.2.1. The designation of functions or a set of functions (hereinafter referred to as functions) performed by an element is formed from capital letters of the Latin alphabet, Arabic numerals and special characters written without spaces. The number of characters in the function designation is not limited, however, one should strive for their minimum number while maintaining unambiguous understanding each designation.2.2.2. The designations of the functions of the elements are given in table. 2.

table 2

Name	Designation
1. Buffer
2. Calculator:
computer section
computing device
3. Calculator
4. Divider
5. Demodulator
6. Demultiplexer
7. Decoder
8. Discriminator
9. Display
10. Peripheral programmable interface
11. Inverter, repeater
12. Comparator
13. Microprocessor
14, Modulator
15. Modifier
16. Memory
17. Main memory
18. Main memory
19. Fast memory
20. “First-in, first-out” memory
21. Read Only Memory (ROM):
programmable ROM (PROM)
Reusable EEPROM (REPROM)
Ultraviolet erasable reprogrammable EPROM (UV EPROM)
22. Random Access Memory (RAM):
Static random access RAM (RAM)
Dynamic random access RAM (RAM)
non-volatile RAM (ENOSU)
23. Associative storage device
24. Programmable Logic Array (PLA)
25. Converter
Notes: 1. The letters X and Y can be used to represent the information presented at the inputs and outputs of the converter, for example:
analog
digital
binary
decimal
BCD
octal
hexadecimal
Gray code
seven-segment
TTL level
MOS level
ESL level
2. Designations allowed:
digital-to-analog converter
analog-to-digital converter
26. Bus transceiver
27. Processor
Processor section
28. Register
Shift register n-bit
29. Adder
30. Counter:
n-bit counter
modulo n counter
31. Trigger
Two stage trigger
Note. It is allowed not to indicate the function designation when executing UGO triggers
32. Multiplier
33. Amplifier
34. Device
35. Arithmetic-logical device
36. Priority coding device
37. Switching device, electronic key
38. Tire
39. Encryptor
40. Delay element
41. Logical element:	³ n or > = n
"majority"
"exclusive OR"
"logical AND"
Note. When performing UGO using computer output devices, it is allowed to designate the function
"logical AND"
"logical OR"
"n and only n"
"odd"	2k + 1 or 2K + 1
"parity"
42. Installation logic element:
"montage OR"
"montage I"
43. Monostable element, single-vibrator:
with restart
without restart
44. Non-logical element:
stabilizer, general designation
Voltage regulator
current stabilizer
45. Sets of non-logical elements
resistors
capacitors
inductances
diodes
diodes with polarity indication
transistors
transformers
indicators	according to GOST 2.764
fuses
combined, for example, diode-resistor
46. Unstable element, generator:
general designation
Note. If the waveform is obvious, the designation “G” without “ ” is acceptable.
with start synchronization
with stop synchronization at the end of the pulse
with synchronized start and stop
square pulse generator
continuous pulse generator
ramp generator
sine wave generator
47. Threshold element, hysteresis

2.2.3. The “*” sign is placed before the function designation of an element if all its outputs are non-logical. 2.2.4. It is allowed to add technical characteristics of the element to the right of the function designation, for example:

resistor with a resistance of 47 Ohms - *R 47.

The element delay is indicated as shown in Fig. 5.

If the two delays are equal, then only one value of 10 ns is specified. Notes 1. Delay, expressed in seconds or in units based on the number of words or bits, can be specified either inside or outside the delay element UGO loop. 2. It is allowed to indicate the delay value as a decimal number: 3 or DEL3, and the value of the delay unit must be specified on the diagram field or in technical requirements 3. In the UGO element, it is allowed to omit the space between the numerical value and the unit of measurement, for example RAM16K, 10 ns, + 5 V.2.2.5. If it is necessary to indicate a complex function of an element, a composite (combined) function designation is allowed. For example, if an element performs several functions, then the designation of its complex function is formed from several simpler function designations, and their sequence is determined by the sequence of functions performed by the element: four-bit counter with decoder at the output of CTR4DC; converter/amplifier of binary coded decimal code to seven-segment code BCD/7SEG>. The designation of a complex element function can also be composed of a function designation and an output label explaining this function designation, with the output label appearing before the function designation, for example: accelerated transfer generator CPG; data register DRG; selector (selection device) SELDEV.2.2.6. When using designations of functions of elements not established by this standard, they must be explained in the diagram field.

2.3. Designation of element pins

2.3.1 The pins of the elements are divided into those that carry and those that do not carry logical information. The pins that carry logical information are divided into static and dynamic, as well as direct and inverse. 2.3.2. On a direct static output, a binary variable has the value “1” if the signal on this pin in the active state is in the “logical 1” state (hereinafter referred to as LOG1) in the accepted logic convention. On an inverse static output, a binary variable has a value “1” if the signal on this pin in the active state is in the “logical 0” state (hereinafter referred to as LOG0) in the received logic convention. On the direct dynamic output, the binary variable has the value “1” if the signal on this pin changes from the LOG0 state to the LOG1 state in the received logical agreement. On the inverse dynamic output, the binary variable has the value “1” if the signal at this pin changes from the LOG1 state to the LOG0 state in the accepted logical agreement. 2.3.3 Properties of the outputs in accordance with paragraphs. 2.3.1 and 2.3.2 are indicated by pointers (Table 3)

Table 3

Name	Designation
Name
1. Direct static input
2. Direct static output
3. Inverted static input
4. Inverted static output
5. Direct dynamic input
6. Inverse dynamic input
7. Static input with polarity indicator
8. Static output with polarity indicator
9. Dynamic input with polarity indicator Note to paragraphs. 7 - 9. Pointers are used when the LOG1 state corresponds to a less positive level.
10. Conclusion that does not carry logical information:
pictured left
pictured on the right

Notes: 1. Form 1 is preferred. 2. When performing UGO using computer output devices, it is allowed to perform: inverse static input, output - with the letter O; direct dynamic input - symbol > or /; inverse dynamic input - symbol< или \; вывод, не несущий логической информации - буквой X.2.3.4. Указатель нелогических выводов не проставляют на выводах УГО элемента, если перед обозначением его функции проставлен знак «*» нелогического элемента.2.3.5. Функциональное назначение выводов элемента обозначают при помощи меток выводов.Метку вывода образуют из прописных букв латинского алфавита, арабских цифр и (или) специальных знаков, записанных в одной строке без пробелов.Количество знаков в метке не ограничивается, но по возможности должно быть минимально при сохранении однозначности понимания каждого обозначения.Обозначения основных меток выводов элементов приведены в табл. 4.

Table 4

Name	Designation
1. Address
2. Byte
3. Bit:
Jr
senior
4. Lock:
ban
capture
5. Fault signal blocking
6. Input (information)
7. Vector
8. Branching
9. Recovery
10. Double-threshold input, hysteresis input
11.Associative storage device request input
12. Countdown input (decrease input)
13. Input operand on which one or more mathematical operations are performed
Notes: 1. The n parameter is replaced by the decimal equivalent of this bit. If the values of all inputs Pn are powers of base 2, n can be replaced by binary exponent.
2. If there is a second operand, its designation is preferably “Q”.
14. Direct count input (increase input)
Note to paragraphs 12, 14. Parameter n should be replaced with the value by which the contents of the counter are increased or decreased
15. An input that causes the element's output to change state to additional every time it accepts the LOG1 state
16. Digital comparator inputs:
more
less
equals
17. Choice (selection)
18. Address selection:
column
lines
19. Crystal selection, memory access
20. Conclusion (information)
21. Bidirectional output	< >or "
22. The output is free (not having any internal connections in the element)
23. Fixed mode (state) output
24. An output whose state change is delayed until the signal causing the change returns to its original level
25. Open output (for example, open collector output, open emitter output)
26. Open H-type output (for example, open collector of pnp transistor, open emitter of npn transistor, open drain of P channel, open source of N channel)
27. Open L-type output (for example, open collector of n-p-n transistor, open emitter of p-n-p transistor, open source of P channel, open drain of N channel)
28 Tri-state output
Note. When performing design documentation using a computer output device, the designation is allowed
29. Memory-associative comparison output
30. Digital comparator output:
more	* > * or * >
less	* < * или * <
equals	* = * or * =
Note. The “*” sign must be replaced with operand designations (clause 13)
31. Generation
32. Readiness
33. A group of pins combined inside an element:
inputs
exits
34. Grouping the bits of a multi-bit input or output
Note. n ... m are replaced by decimal equivalents of real significance or binary order. Intermediate values between n and m may be omitted
35. Grouping connections:
input
weekend
Note. The designation is used when it is necessary to indicate that several pins are used to transmit the same information
36. Data:
input
weekend
sequential
Note. For storage devices the following designations are allowed:
input information
output information
37. Upload (parallel recording enabled)
38. Delay
39. Double delay
40. Loan:
loan taker input
loan outlet
loan formation
loan distribution
41. Busy
42. Write (write command)
43. Request
44. Service request
45. Sign
46. Imitation
47. Inversion (negation)
48. Instructions, command
49. Handshake
50. Code
51. Switching (electronic)
52. The End
53. Correction
54. "logical 0"	LOGO or LOG0
55. "logical 1"
56. Mask, disguise
57. Marker
58. Multiplexing
59. Odd parity
60. Waiting
61. Operation
62. Stop
63. Answer
64. Refusal
65. Cleaning
66. Error
Error word
67. Transfer
68. Transfer:
carry input
carry-propagating output
transfer formation
transfer propagation
69. Overflow
70. Acknowledgment
71. Position
72. Interrupt:
interrupt acknowledge
programmable interrupt
73. Reception
74. Priority
75. Continued
76. Start, beginning
77. Work
78. Resolution
79. Allowing the passage of pulses, circuit operation
80. Resolution of the third state
Note. When performing UGO using computer output devices, the designation is allowed
81. Mode
82. The result is zero
83. Reset:
general
reset
84. Shift:
from left to right and top to bottom (from least significant to most significant)
from right to left or from bottom to top (from most significant to least significant)
Note. The n parameter should be replaced with the actual value of the positions by which the shift occurs. When n = 1 this value can be omitted.
left or right
85. Synchronization
86. Condition
87. Medium
88. Strobe (sampling signal)
89. Score:
input specifying the element's contents
output indicating the contents of the element
Note. The "*" sign should be replaced with the value of the element's contents
90. Reading (reading)
91. Tact
92. Management
93. Condition
94. Setting to “1”
95. Installation of JK trigger:
to LOG1 state (J-input)
to LOG0 state (K-input)
96. Function
97. Parity

2.3.6. The designation of the main labels indicating the functional purpose of the pins that do not carry logical information is given in table. 5.

Table 5

Name	Designation
1. Power output from voltage source
Notes:
1. When performing UGO using computer output devices, the designation is allowed
2. Designation allowed
3. The supply voltage rating is indicated next to the UGO above or next to the output line, for example
It is allowed to put the voltage rating inside the UGO instead of the output label, for example
4. Explanatory information may be placed before the output label, for example:
serial number;
power indicator of the digital part of the element;
analog power indicator
2. Common terminal, ground, housing
Notes:
1. Designation allowed.
2. Before the output mark, it is allowed to put an indicator of the general output of the digital part and an indicator of the general output of the analog part
3. Current
Notes:
1. Instead of the designation “I” you can put its value, for example
2. It is allowed to put a serial number before the output label, for example
4. Terminal for connecting a capacitor
5. Terminal for connecting a resistor
6. Terminal for connecting inductance
7. Lead for connecting a quartz resonator
8. Field-effect transistor terminals:
source
drain
gate
9. Conclusions of n-p-n and p-n-p transistor:
collector
base
emitter
npn transistor emitter
emitter pnp transistor

2.3.7. If it is necessary to indicate a complex function of the outputs, it is possible to construct a composite label formed from the main labels, and it is recommended to follow the reverse order of attaching the labels, for example: RDA read address; DBY data byte; BYSEL byte selection. To designate an output label that alternately has two functions, these functions are indicated through a slash, for example: input/output I/O; write/read WR/RD; control/data C/D. Notes: 1. The order of the labels determines the logical level of the enabling signal: the first function is performed at LOG1, the second - at LOG0. 2. The order of pin labels that do not carry logical information is arbitrary. 3. When performing a UGO of an element that has two ports for receiving and transmitting information: A and B, the output label A/B means permission to receive information by port A and transmit information by port B at the logical signal level at this pin equal to LOG1.2.3.8. It is allowed to use the function designations given in Table 1 as pin labels. 2, for example: COMP comparison; the result of the P-Q subtraction operation. It is also possible to compose a complex output label from the function designation and output label, and the direct order of their attachment is recommended, for example: reading from memory RDM.2.3.9. When depicting a compound function or output label, it is allowed to execute it in two lines - one below the other, for example: RAM; DOUT.256´1< >2.3.10. If it is necessary to display a free output in the UGO (without connections inside the element), then it must have an output pointer that does not carry logical information and have an output label “NC”. 2.3.11. The power supply pins of the elements are either text information on a free field of the diagram, or in one of the ways shown in Fig. 6. Note. In one set of design documentation it is allowed to use either the methods shown in Fig. 6a and 6b, or to hell. 6a and 6c.2.3.12. The numbering of the element pins is given above their pin line on the left for inputs or on the right for outputs from the UGO circuit or the output indicator - if available. Note. It is allowed to number the outputs of elements in a break in the output line. 2.3.13. When using terminal labels not specified by this standard, they should be given in the UGO in brackets and explained in the field of the diagram (Fig. 7) or in the regulatory and technical documentation for the product.

Note. It is allowed to supplement the output label established by this standard with an explanatory output label not established by this standard, and it is placed in parentheses and, if necessary, explained in the diagram field, for example: EN (P/S) - permission for parallel or serial connection of triggers within an element .

2.4. Designation of pin groups

2.4.1. The conclusions of the elements are divided into logically equivalent, i.e. interchangeable without changing the function of the element, and logically unequal.2.4.2. The UGO of an element is performed without additional fields or without a right or left additional field, in the following cases: all pins are logically equivalent; the functions of the pins are uniquely determined by the function of the element. In this case, the distances between the pins must be the same, and pin labels are not indicated. 2.4.3. If there are logically equivalent inputs or outputs of an element, they can be graphically combined into a group of outputs, which are assigned a label indicating their function. This mark is placed at the level of the first output of the group (Fig. 8).

Note. The numbering of the pins of such groups of logically equivalent pins can be specified in any order. 2.4.4. If several consecutive pins have parts of labels that reflect the same functions, then such pins can be combined into a group of pins, and this part of the label is placed in a group label. A group mark is placed above a group of marks that must be written without space between lines (Fig. 9).

2.4.5. Groups of pins are separated by one line spacing or placed in a separate zone for each group. 2.4.6. From several group labels, a group label of a higher order can be selected. This label is placed above the groups of pins to which it belongs, separated from them by an interval. Groups that belong to a group label of a higher order are placed in a separate zone (Fig. 10).

Note. It is allowed to omit the space between groups of pins that have a higher order label.2.4.7. The numbers of digits in groups of pins are indicated by numbers in the natural series, starting from zero. In this case, pin labels are assigned in one of the ways presented in Fig. eleven.

Note. For outputs, pin labels consisting only of digit numbers are allowed. Only the labels of an open output and an output with three states are required. If weight coefficients are uniquely defined in a group of discharges, then instead of the discharge number its weighting coefficient can be entered. For example, for binary notation the series of weights has the form 2 0, 2 1, 2 2, 2 3, ... = 1, 2, 4, 8, ... Then the information input of the zero digit will be labeled D1 or 1, the third digit - D8 or 8.2.4.8. If it is necessary to number groups and digits within a group, the label of each output will consist of the group number (first digit) and the digit number in the group, separated from each other by a dot, for example: information input label of the first digit of the zero group: D0.1. Note. If there are two information channels (ports) in an element, it is allowed to designate them A and B, which are taken out as a group label for information inputs and (or) outputs, if this does not lead to ambiguity in understanding the output labels. 2.4.9. Bidirectional output is indicated by the label "< >"or """, which is placed either in the UGO of the element - above or next to the function label (group function label) of the output (outputs) - damn. 12a and damn. 12b, respectively, or at the terminals of the element (Fig. 12c). In this case, the labels of the pins indicating the input and output functions are marked with a slash. Note. It is allowed to place the labels of the input and output functions of the output above and below the label of the bidirectional output, respectively (Fig. 12d).

2.5. Connection of pins

2.5.1. The outputs of the elements are divided into influencing and dependent. An influencing pin affects one or more pins that depend on it.2.5.2. To indicate the relationship of the element's pins, a dependency designation is used. The designation of the dependency of the pins is carried out by assigning pin labels to them: for an influencing pin - a letter designation of the dependence in accordance with Appendix 3 and a serial number placed after the letter designation without a space; for each dependent on a given influencing pin - the same serial number, placed without a space before the letter designation of the output label assigned to it in accordance with table. 4, or instead of it. If the influencing pin affects the dependent pin with its additional logical state, then a dash is placed above the serial number placed before the dependent pin label (Fig. 13a). If the pin is dependent on several influencing pins, the serial number each of them must be indicated separated by commas (Fig. 13b). Note. It is allowed to supplement the dependency designation with a label explaining the functional purpose of the output, which is placed in parentheses.

2.5.3. If the output performs several functions and (or) has several influencing effects, then the designation of each of these functions and (or) dependencies with the corresponding label can be shown either in subsequent lines, and each label can be associated with a pointer (Fig. 14a) , or on one line through a slash (Fig. 14b). The order of labels representing multiple functions or dependencies is arbitrary. Note. When specifying several labels of one pin in subsequent lines, it is allowed that the pin lines do not connect to them.

3. INSTALLATION LOGIC DESIGNATION

3.1. The direct connection of the logical outputs of several elements to a common load (installation logic) should be indicated as shown in Fig. 15a.3.2. Installation logic can be considered conditionally as an element that is depicted as a UGO element of installation logic (Fig. 15b). Notes to paragraphs. 3.1, 3.2: 1. The term “installation logic element” corresponds to the term “DOT element”. 2. Depending on the type of logical function being performed, the “*” sign should be replaced with the sign “&” (“edit AND”) or the sign “1” (“edit OR”). 3. It is allowed to depict the installation logic as shown in Fig. 15c, if this does not lead to ambiguity of understanding. 4. If the element outputs are assigned open output labels, it is allowed to display the installation logic in accordance with the drawing. 15

4. ABBREVIATION OF UGO GROUPS

4.1. To reduce the volume of documentation, abbreviated designation of UGO groups is allowed.4.2. The UGO elements can be depicted combined, adjacent to each other on one or two sides, parallel to the distribution of information (Fig. 16a). In this case, there is no logical connection between these elements. Note. It is allowed to depict UGO elements with a common side perpendicular to the dissemination of information (Fig. 16b). In this case, there is at least one logical connection between these elements. Logical connections should be indicated in accordance with Appendix 4. In the absence of such instructions, it is considered that there is only one logical connection between these elements (Fig. 16c).

4.3. UGO groups of similar elements, depicted in combination and having the same information and common conclusions, can contain a common graphic block - a control block (Appendix 3). It is allowed to designate the control unit as shown in Fig. 17.

4.4. In a group of elements depicted together and containing the same information in the main field of the UGO, the latter is placed in the upper UGO (Fig. 18a). It is allowed to separate such elements from each other with a dashed line (Fig. 18b). Two consecutive groups of elements should be depicted as shown in Fig. 18th century An abbreviated designation for a group of pairs of elements is shown in Fig. 18d. A group of elements with identical terminals (inputs and outputs), having a common control unit and not having it, can be depicted as shown in Fig. 18d and damn. 18g respectively.

4.5. In circuits that have elements with a large number of terminals of the same functional purpose, abbreviated designation of such elements is allowed (Fig. 19).

Pin number
Output label
Pin number
Output label

Notes: 1. The records of pins 13 - 17 and 13 ... 17 are identical. 2. The table (the first method of abbreviated designation of elements) should be placed in the diagram field.4.6. In circuits with repeating elements, it is also possible to use the batch method of information compression, i.e. package image of UGO elements and their communication lines. 4.6.1. A package of elements is a group of similar elements depicted as one UGO. A package of signals is a group of signals (logical connections of elements) depicted by one line. Packages of elements and signals are explained in the diagram using information packages, 4.6.2. An information package is a brief listing of the following data: signal identifiers (logical connections of elements); design addresses of elements and signals; coordinates of elements on the diagram; number of elements or signals in the package, etc. 4.6.3. A short record of the information package can be presented as follows: 0,1; 0.1; 0.1; 0,1 = (0,1) 4 - sequence 0,1 is repeated 4 times; 0, 0, 0, 1, 1, 1 = 3 (0,1) - each element of the specified sequence is repeated 3 times in a row.4.6.4 . A batch image of information is used when the following conditions are simultaneously met: uniformity of elements in a group; uniformity of input and output signals of group elements; regularity of signals in each packet, allowing for their convenient listing. 4.6.5. Inside the main field of the UGO of the package of elements, the following is placed: in the first three lines, information is in accordance with GOST 2.708; in subsequent lines, information about the package. If there is not enough space in the main field, information about the package of elements can be placed in the diagram field. For example, to the right of the UGO of a package of elements. An example of a UGO of a package of elements is shown in Fig. 20.

5. EXAMPLES OF UGO ELEMENTS

5.1. Examples of UGO elements are given in table. 6 - 15 for positive logic convention. The given letter designations of functions and element pin labels are mandatory, with the exception of the alternative ones given in table. 2 or in table. 4 (in parentheses). In this case, it is possible not to indicate serial numbers in the pin labels when indicating the dependency. The order of the pin labels (groups of pin labels - if any) is recommended. The pointers of the pins of the elements are given in the preferred form 1 table. 3, however, it is allowed to use all forms of indicators given in table. 3.5.2. Examples of UGO logic elements are given in table. 6.

Table 6

Name	Designation
1. Element "NO"
2. Element 3I-NOT
3. Element 2I-NOT with an open collector output and increased load capacity
4. Element 3OR-NO
5. Combined 2I-OR element with inverted output
6. Element 4I-NET with an open collector at the output
7. 2I-OR element with inverted output and expansion input
8. Expander
9. Even or Odd Element

5.3. Examples of UGO transceiver elements are given in table. 7.

Table 7

5.4. Examples of UGO hysteresis elements are given in table. 8.

Table 8

5.5. Examples of UGO converters (decoders) and encoding devices (encoders) are given in Table. 9.

Table 9

Name	Designation
1. BCD to Decimal Converter
2. Converter from three lines to eight
3. Binary to BCD Converter
4. Converter-amplifier of binary code to seven-segment. Note. It is allowed to replace lowercase letters with uppercase ones: A, B, C, D, E, F, G
5. Priority encoder (priority encoder) from 8 lines to 3 lines (GS - “group signal”)
6. Two decryptors that accept a two-digit code. Note. It is allowed to designate decoders A and B, which are displayed as a group label of the outputs of the corresponding decoder
7. Converter TTL levels to MOS levels
8. Converter of ESL levels to TTL levels. Note to paragraphs. 7 and 8. The designation of the signal converter function / can be replaced by the designation // if it is necessary to indicate the presence of a galvanic connection between its inputs and outputs

5.6. Examples of UGO multiplexers and demultiplexers, as well as switches of digital and analog signals are given in Table. 10.

Table 10

Name	Designation
1. Multiplexer for 8 inputs with strobe. Note. The EN gate input may be designated STR
2. 8-line demultiplexer
3. Four-channel multiplexer with two inputs each
4. Two-channel multiplexer with 4 inputs each. Note to paragraphs. 3, 4. When designating multiplexer channels not by serial numbers (1, 3, etc.), but by the letters A, B, etc.), to eliminate ambiguity in understanding, the data address input is assigned the “Select” label: SEL or SE
5. Electronic switch

5.7. Examples of UGO arithmetic elements are given in table. eleven.

Table 11

Name	Designation
1. Full single-bit adder
2. Four-bit adder-subtractor
3. 4-bit full adder
4. Four-bit high-speed ALU
5. Fast forward generator for ALU
6. Four-bit digital comparator

5.8. Examples of UGO triggers (bistable elements) are given in table. 12.

Table 12

Name	Designation
1. Two triggers with separate triggering (RS-type), one with an additional input
2. Two D-type delay flip-flops
3. Six D-flip-flops with common control and reset inputs
4. Edge-triggered D-type flip-flop
5. J K-type flip-flop, edge triggered
6. Universal JK flip-flop with master-helper structure
7. Two JK flip-flops with common control and reset inputs

5.9. Examples of UGO monostable (multivibrators) and unstable elements are given in table. 13.

Table 13

5.10. Examples of UGO registers and counters are given in table. 14.

Table 14

ANNEX 1

LOGICAL CONVENTION

1. Binary logic deals with variables that can take two logical states - the “logical 1” state (hereinafter referred to as LOG1) and the “logical 0” state (hereinafter referred to as LOG0). The logical function symbols defined by this standard represent the relationship between inputs and outputs of elements in terms of logical states not related to physical implementation.2. With a specific physical implementation of elements, logical states are represented by physical quantities (electric potential, pressure, luminous flux, etc.). Logic does not require knowledge of the absolute value of a quantity, so a physical quantity is simply identified as more positive - H and less positive - L (Fig. 21). These two values are called logical levels.

3. Correspondences between these concepts are established by the following agreements:

Positive logic convention

A more positive value of the physical quantity (logical level H) corresponds to LOG1. A less positive value of a physical quantity (logical level L) corresponds to LOG0.

Negative Logic Convention

A less positive value of a physical quantity (logical level L) corresponds to LOG1. A more positive value of the physical quantity (logical level H) corresponds to LOG0.4. To indicate the correspondence between logical states and the values of these states, two methods are used: the method of a single agreement for the entire circuit (positive logic agreement or negative logic agreement); using a polarity indicator.5. To establish a one-to-one correspondence in the circuit between the logical state and the logical level at the element output, use the inversion pointer (0) or the polarity pointer (or).6. The inversion pointer is used if a single agreement is adopted for the entire circuit (as in Fig. 21). If the circuit uses positive and negative logic conventions, an indicator of the polarity of the outputs for which the negative logic convention is valid should be used. In a circuit with polarity indicators, the pointer inversions are not used.7. The diagram field or technical requirements must indicate in what logic the diagram is implemented.8. Logic gates can have logical equivalent forms. For example, an element having a truth table expressed in signal levels, which is shown in Fig. 22a, has equivalent forms in positive logic and in negative logic, presented in hell. 22b and damn. 22v accordingly.

Name	Designation
1. 4-bit shift register with parallel inputs
2. 4-bit serial-parallel shift register with direct and additional code at the output (T/C - input for switching the code at the outputs: direct or additional; P/S - input that controls the connection of register bits in series or parallel)
3. Shift 4-bit bidirectional general purpose register
4. Universal 8-bit register
5. 8-bit shift register with dual serial input and parallel outputs
6. Shift 8-bit universal register with serial and parallel inputs and outputs (A/S - input, mode switching: asynchronous or synchronous; ALD - input allowing parallel recording of information in channel A)
7. 8-bit shift register with parallel loading
8. Binary 14-bit counter with carry-through
9. Asynchronous decimal counter consisting of dividers by 2 and by 5 with parallel recording

APPENDIX 2

Table 16

CONTOUR SYMBOLS

Name	Designation
1. Main circuit (corresponding to that shown in Figure 1 of this standard)
2. General control circuit Note: The circuit of the general control unit is located above the main circuit
3. Common output element circuit Note. The contour of the common output element is located under the main contour

Notes: 1. The ratio of the length of the circuits to their width is not set and is determined by the information placed in the circuit and the number of pins. 2. It is allowed to indicate a common output element in the circuit of a common control unit (for example, output “ST-9” of the UGO meter, Table 14, clause 12). Examples of UGO with control circuits and a common output element are shown in Fig. 23a and damn. 23b respectively.

APPENDIX 3

Table 17

RELATIONSHIP OF OUTPUT

Dependency type	Letter designation	Effect on dependent output
Dependency type	Letter designation
ADDRESS		Action allowed (address selected)	Action blocked (address not selected)
CONTROL		Action allowed	Action blocked
PERMISSION		Action allowed	The action of the dependent output is blocked: the external state “high impedance” (HI) is set to the output with an open circuit or with three states: level L (H) VI is set to the open circuit output type H (L), the remaining outputs are set to LOG0 state
AND		Action allowed	The state is set to LOG0
MODE		Action allowed (mode selected)	Action blocked
NEGATION		Additional internal state	Internal state unchanged
SETTING TO "0"		Internal output state as for S = 0, R = 1
INSTALLATION IN "1"		Internal output state as for S = 1, R = 0	Internal state unchanged
OR		State LOG1 is set	Action allowed
INTERCONNECTION		State LOG1 is set	The state is set to LOG0

* This column shows the state of the influencing output. ** Pseudo-stable condition.

APPENDIX 4

Table 18

INTERNAL JOINS *

Name	Designation
1. Internal connection (the internal state of LOG1 (LOG0) of the input of the right element corresponds to the internal state of LOG1 (LOG0) of the output of the left element)
The internal state of LOG1 (LOG0) of the right element corresponds to the internal connection of LOG0 (LOG1) of the output of the left element). Note. The vertical line may cross the inversion indicator "0".
3. Internal connection with a dynamic characteristic (the internal state LOG1 of the input of the right element appears only when the output of the left element transitions from LOG0 to LOG1, in all other cases the internal state of the input of the right element is LOG0)
4. Internal connection with negation, which has a dynamic characteristic
5. Internal (virtual) input (this input is in the LOG1 state, unless it is changed by an input with a predominant or modifying dependence, the designation of which is displayed to the right of the first input in accordance with Table 17.
6. Internal (virtual) output (the effect of this output on the internal input with which it is connected is determined by the type of dependence in accordance with Table 17, the designation of which is shown to the right of this output) Notes to paragraphs. 5 and 6: 1. Internal (virtual) inputs and outputs have only one internal logical state. 2. Only the pin pointers given in Table 1 are applicable to internal (virtual) inputs and outputs. 3, paragraph 5 of this standard.

* An internal connection is a connection within an element (internal inputs and outputs).

APPENDIX 5

Table 19

The ratios of the dimensions of the UGO on the modular grid are given in Table. 19.

Name	Designation
1. Minimum distance between lead lines
2. General control unit
3. Common output element
4. Polarity indicator, such as static input with polarity indicator
5. Inverted output indicator, such as inverted static input
6. Dynamic output indicator, such as inverse dynamic input
7. Pointer to an output that does not carry logical information, such as the one shown on the left
8. Bidirectional output label, for example:
shown from the entrance
shown with polarity indicator
20. Designation of the “Exclusive OR” function
21. Analog signal designation
23. Digital signal designation

INFORMATION DATA

1. DEVELOPED AND INTRODUCED by the Committee for Standardization and Metrology of the USSR DEVELOPERS: V.V. Dolgopolov, Ph.D. tech. sciences; V.Yu. Gulenkov, Ph.D. tech. sciences; S.S. Borushek, L.G. Yurganova, V.V. Gugnina2. APPROVED AND ENTERED INTO EFFECT by Resolution of the Committee of Standardization and Metrology of the USSR dated December 23, 1991 No. 23753. The standard complies with the international standard IEC 617-12 in terms of section. 54. INSTEAD GOST 2.743-825. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS

	Item number
GOST 2.304-81
GOST 2.708-81
GOST 13.1.002-80
GOST 17021-88
GOST 26975-86

If for an ordinary person the perception of information occurs by reading words and letters, then for mechanics and installers they are replaced by alphabetic, digital or graphic symbols. The difficulty is that while the electrician completes his training, gets a job, and learns something in practice, new SNiPs and GOSTs appear, according to which adjustments are made. Therefore, you should not try to learn all the documentation at once. It is enough to gain basic knowledge and add relevant data as you work.

For circuit designers, instrumentation mechanics, electricians, the ability to read an electrical diagram is a key quality and indicator of qualification. Without special knowledge, it is impossible to immediately understand the intricacies of designing devices, circuits and methods of connecting electrical units.

Types and types of electrical circuits

Before you begin to study the existing symbols of electrical equipment and its connections, you need to understand the typology of circuits. On the territory of our country, standardization has been introduced according to GOST 2.701-2008 dated July 1, 2009, according to “ESKD. Scheme. Types and types. General requirements".

Based on this standard, all schemes are divided into 8 types:

United.
Located.
Are common.
Connections.
Installation connections.
Completely principled.
Functional.
Structural.

Among the existing 10 species listed in this document, highlight:

Combined.
Divisions.
Energy.
Optical.
Vacuum.
Kinematic.
Gas.
Pneumatic.
Hydraulic.
Electrical.

For electricians, it is of greatest interest among all the above types and types of circuits, as well as the most popular and often used in work - an electrical circuit.

The latest GOST, which came out, has been supplemented with many new designations, current today with code 2.702-2011 dated January 1, 2012. The document is called “ESKD. Rules for the execution of electrical circuits” refers to other GOSTs, including the one mentioned above.

The text of the standard sets out clear requirements in detail for electrical circuits of all types. Therefore, when performing installation work with electrical circuits, this document should be used as a guide. The definition of the concept of an electrical circuit, according to GOST 2.702-2011, is as follows:

“An electrical diagram should be understood as a document containing symbols of parts of a product and/or individual parts with a description of the relationship between them and the principles of operation from electrical energy.”

Once defined, the document contains rules for the implementation on paper and in software environments of contact connection designations, wire markings, letter designations and graphic representations of electrical elements.

It should be noted that most often only three types of electrical circuits are used in home practice:

Assembly– for the device it is displayed printed circuit board with the arrangement of elements with a clear indication of the location, value, principle of fastening and connection to other parts. Electrical wiring diagrams for residential premises indicate the number, location, rating, connection method and other precise instructions for the installation of wires, switches, lamps, sockets, etc.
Fundamental– they indicate in detail the connections, contacts and characteristics of each element for networks or devices. There are complete and linear circuit diagrams. In the first case, control, control of elements and the power circuit itself are depicted; in a linear diagram, they are limited only to the circuit with the remaining elements depicted on separate sheets.
Functional– here, without detailing the physical dimensions and other parameters, the main components of the device or circuit are indicated. Any part can be depicted as a block with a letter designation, supplemented by connections with other elements of the device.

Graphic symbols in electrical diagrams

The documentation, which specifies the rules and methods for graphically designating circuit elements, is represented by three GOSTs:

2.755-87 – graphic symbols of contact and switching connections.
2.721-74 – graphic symbols of parts and assemblies for general use.
2.709-89 – graphic symbols in electrical diagrams of sections of circuits, equipment, contact connections of wires, electrical elements.

In the standard with code 2.755-87, it is used for diagrams of single-line electrical panels, conventional graphic images (CGI) of thermal relays, contactors, switches, circuit breakers, and other switching equipment. There is no designation in the standards for automatic devices and RCDs.

On the pages of GOST 2.702-2011, it is allowed to depict these elements in any order, with explanations, decoding of the UGO and the circuit diagram of the difavtomat and RCD itself.
GOST 2.721-74 contains UGOs used for secondary electrical circuits.

IMPORTANT: To designate switching equipment there is:

4 basic UGO images

9 functional signs of UGO

*UGO*	*Name*
	Arc suppression
	No self-return
	With self-return
	Limit or travel switch
	With automatic operation
	Switch-disconnector
	Disconnector
	Switch
	Contactor

IMPORTANT: Designations 1 – 3 and 6 – 9 are applied to the fixed contacts, 4 and 5 are placed on the moving contacts.

Basic UGO for single-line diagrams of electrical panels

*UGO*	*Name*
	Thermal relay
	Contactor contact
	Switch - load switch
	Automatic - circuit breaker
	Fuse
	Differential circuit breaker
	RCD
	Voltage transformer
	Current transformer
	Switch (load switch) with fuse
	Motor protection circuit breaker (with built-in thermal relay)
	A frequency converter
	Electricity meter
	Normally closed contact with reset button or other push-button switch, with reset and opening by means of a special actuator of the control element
	Normally closed contact with push-button switch, with reset and opening by retracting the control button
	Normally closed contact with push-button switch, reset and open by pressing the control button again
	Normally closed contact with push-button switch, with automatic reset and opening of the control element
	Delayed closing contact that initiates upon return and operation

	Delayed closing contact which is only initiated when triggered
	Delayed closing contact which is actuated by return and tripping
	Delayed closing contact which only operates on return
	Delayed closing contact that only switches when triggered
	Timing relay coil
	Photo relay coil
	Pulse relay coil
	General designation of a relay coil or contactor coil
	Indication lamp (light), lighting
	Motor drive
	Terminal (separable connection)
	Varistor, surge arrester (surge suppressor)
	Arrester
	Socket (plug connection): Pin Nest
	A heating element

Designation of measuring electrical instruments to characterize circuit parameters

GOST 2.271-74 accepts the following designations in electrical panels for buses and wires:

Letter designations in electrical diagrams

The standards for the letter designation of elements on electrical circuits are described in the GOST 2.710-81 standard with the text title “ESKD. Alphanumeric designations in electrical circuits." The mark for automatic devices and RCDs is not indicated here, which is prescribed in clause 2.2.12 of this standard as a designation with multi-letter codes. The following letter codings are accepted for the main elements of electrical panels:

*Name*	*Designation*
Automatic switch in the power circuit	QF
Automatic switch in the control circuit	SF
Automatic switch with differential protection or difavtomat	QFD
Switch or load switch	QS
RCD (residual current device)	QSD
Contactor	K.M.
Thermal relay	F, KK
Timing relay	KT
Voltage relay	KV
Impulse relay	KI
Photo relay	KL
Surge arrester, arrester	F.V.
fuse	F.U.
Voltage transformer	TV
Current transformer	T.A.
A frequency converter	UZ
Ammeter	PA
Wattmeter	PW
Frequency meter	PF
Voltmeter	PV
Active energy meter	P.I.
Reactive energy meter	PK
Heating element	E.K.
Photocell	B.L.
Lighting lamp	EL
Light bulb or light indicating device	H.L.
Plug or socket connector	XS
Switch or circuit breaker in control circuits	S.A.
Push-button switch in control circuits	S.B.
Terminals	XT

Representation of electrical equipment on plans

Despite the fact that GOST 2.702-2011 and GOST 2.701-2008 take into account this type of electrical circuit as a “layout diagram” for the design of structures and buildings, one must be guided by the standards of GOST 21.210-2014, which indicate “SPDS.

Images on the plans of conventional graphic wiring and electrical equipment.” The document establishes UGO on plans for laying electrical networks of electrical equipment (lamps, switches, sockets, electrical panels, transformers), cable lines, busbars, tires.

The use of these symbols is used to draw up drawings of electric lighting, power electrical equipment, power supply and other plans. The use of these designations is also used in basic single-line diagrams of electrical panels.

Conventional graphic images of electrical equipment, electrical devices and electrical receivers

The contours of all depicted devices, depending on the information richness and complexity of the configuration, are taken in accordance with GOST 2.302 on the scale of the drawing according to the actual dimensions.

Conventional graphic designations of wiring lines and conductors

Conventional graphic images of tires and busbars

IMPORTANT: The design position of the busbar must exactly coincide on the diagram with the place of its attachment.

Conventional graphic images of boxes, cabinets, panels and consoles

Conventional graphic symbols of switches, switches

On the pages of documentation GOST 21.210-2014 there is no separate designation for push-button switches, dimmers (dimmers). In some schemes, according to clause 4.7. the normative act uses arbitrary designations.

Conventional graphic symbols of plug sockets

Conventional graphic symbols of lamps and spotlights

The updated version of GOST contains images of lamps with fluorescent and LED lamps.

Conventional graphic symbols of monitoring and control devices

Conclusion

The given graphic and letter images of electrical components and electrical circuits are not a complete list, since the standards contain many special signs and codes that are practically not used in everyday life. To read electrical diagrams, you will need to take into account many factors, first of all, the country of manufacture of the device or electrical equipment, wiring and cables. There is a difference in markings and symbols on the diagrams, which can be quite confusing.

Secondly, you should carefully consider areas such as intersections or lack of a common network for wires located with the overlay. On foreign diagrams, if a bus or cable does not have a common power supply with intersecting objects, a semicircular continuation is drawn at the point of contact. This is not used in domestic schemes.

If the diagram is depicted without complying with the standards established by GOSTs, then it is called a sketch. But for this category there are also certain requirements, according to which, based on the sketch provided, an approximate understanding of the future electrical wiring or design of the device should be drawn up. Drawings can be used to create more accurate drawings and diagrams based on them, with the necessary symbols, markings and compliance with scales.

In this article we will show a table of graphic symbols of radio elements in the diagram.

A person who does not know the graphic designation of the elements of a radio circuit will never be able to “read” it. This material is intended to give the novice radio amateur where to start. Such material is found very rarely in various technical publications. This is precisely why he is valuable. In different publications there are “deviations” from the state standard (GOST) in the graphic designation of elements. This difference is important only for state acceptance authorities, but for a radio amateur it has no practical significance, as long as the type, purpose and main characteristics of the elements are clear. In addition, the designation may be different in different countries. Therefore, this article provides different options for graphically designating elements on a diagram (board). It may well be that you will not see all designation options here.

Any element on the diagram has a graphic image and its alphanumeric designation. The shape and dimensions of the graphic designation are determined by GOST, but as I wrote earlier, they have no practical significance for a radio amateur. After all, if on the diagram the image of the resistor is smaller in size than according to GOST standards, the radio amateur will not confuse it with another element. Any element is indicated on the diagram by one or two letters (the first one must be capitalized), and by a serial number on a specific diagram. For example, R25 means that it is a resistor (R), and in the diagram shown it is the 25th in a row. Sequence numbers are typically assigned from top to bottom and left to right. It happens that when there are no more than two dozen elements, they are simply not numbered. It happens that when modifying circuits, some elements with a “large” serial number may be in the wrong place in the circuit; according to GOST, this is a violation. Obviously, the factory acceptance was bribed with a bribe in the form of a banal chocolate bar, or an unusually shaped bottle of cheap cognac. If the circuit is large, then it can be difficult to find elements that are out of order. With a modular (block) construction of equipment, the elements of each block have their own serial numbers. Below you can find a table containing designations and descriptions of the main radio elements; for convenience, at the end of the article there is a link to download the table in WORD format.

Table of graphic designations of radioelements on the diagram

Graphic designation (options)	Item name	Brief description of the item
	Battery	Single source electric current, including: watch batteries; AA salt batteries; dry batteries; cell phone batteries
	Battery	A set of single elements designed to power equipment with an increased total voltage (different from the voltage of a single element), including: batteries of dry galvanic batteries; batteries for dry, acid and alkaline cells
	Knot	Connection of conductors. The absence of a dot (circle) indicates that the conductors in the diagram intersect, but do not connect to each other - these are different conductors. Does not have an alphanumeric designation
	Contact	A terminal of a radio circuit intended for “rigid” (usually screw) connection of conductors to it. Most often used in large power management and control systems of complex multi-unit electrical circuits
	Nest	Connecting easily removable contact of the “connector” type (in amateur radio slang - “mother”). Used primarily for short-term, easily disconnected connections of external devices, jumpers and other circuit elements, for example as a test socket
	Socket	A panel consisting of several (at least 2) female contacts. Designed for multi-contact connection of radio equipment. A typical example is a 220V household electrical outlet.
	Plug	Contact easily removable pin contact (in the slang of radio amateurs - “dad”), intended for short-term connection to a section of an electrical radio circuit
	Fork	Multi-pin connector, with a number of contacts of at least two, intended for multi-pin connection of radio equipment. A typical example is the power plug of a 220V household appliance.
	Switch	A two-contact device designed to close (open) an electrical circuit. A typical example is a “220V” light switch in a room
	Switch	A three-contact device designed to switch electrical circuits. One contact has two possible positions
	Tumblr	Two “paired” switches - switched simultaneously by one common handle. Separate groups of contacts can be depicted in different parts of the diagram, then they can be designated as group S1.1 and group S1.2. In addition, if there is a large distance in the diagram, they can be connected by one dotted line
	Galetny switch	A switch in which one "slide" type contact can be switched to several different positions. There are paired biscuit switches, in which there are several groups of contacts
	Button	A two-contact device designed to briefly close (open) an electrical circuit by pressing it. A typical example is an apartment doorbell button
	Common wire (GND)	A contact of a radio circuit that has a conditional “zero” potential relative to other sections and connections of the circuit. Typically, this is the output of the circuit, the potential of which is either the most negative relative to the rest of the circuit (minus the circuit's power supply) or the most positive (plus the circuit's power supply). Does not have an alphanumeric designation
	Grounding	The pin of the circuit to be connected to Earth. Allows you to eliminate the possible occurrence of harmful static electricity, and also prevents injury from electric shock in the event of possible contact with dangerous voltage on the surfaces of radio devices and units that are touched by a person standing on wet ground. Does not have an alphanumeric designation
	Incandescent lamp	An electrical device used for lighting. Under the influence of electric current, the tungsten filament glows (it burns). The filament does not burn out because there is no chemical oxidizing agent - oxygen - inside the lamp bulb
	Signal lamp	A lamp designed to monitor (signal) the status of various circuits of outdated equipment. Currently, instead of signal lamps, LEDs are used, which consume lower current and are more reliable.
	Neon lamp	Gas discharge lamp filled with inert gas. The color of the glow depends on the type of filler gas: neon – red-orange, helium – blue, argon – lilac, krypton – blue-white. Other methods are also used to give a certain color to a lamp filled with neon - the use of luminescent coatings (green and red glow)
	Lamp daylight(LDS)	A gas-discharge lamp, including the bulb of a miniature energy-saving lamp, using a fluorescent coating - a chemical composition with an afterglow. Used for lighting. With the same power consumption, it produces brighter light than an incandescent lamp
	Electromagnetic relay	An electrical device designed to switch electrical circuits by applying voltage to the electrical winding (solenoid) of a relay. A relay can have several groups of contacts, then these groups are numbered (for example P1.1, P1.2)
		An electrical device designed to measure the strength of electric current. It consists of a fixed permanent magnet and a movable magnetic frame (coil) on which the arrow is attached. The greater the current flowing through the frame winding, the greater the angle the arrow deflects. Ammeters are divided according to the rated current of the full deflection of the pointer, by accuracy class and by area of application
		An electrical device designed to measure the voltage of an electric current. In fact, it is no different from an ammeter, since it is made from an ammeter by being connected in series to an electrical circuit through an additional resistor. Voltmeters are divided according to the rated voltage of the full deflection of the pointer, by accuracy class and by area of application
	Resistor	A radio device designed to reduce the current flowing through an electrical circuit. The diagram indicates the resistance value of the resistor. The power dissipation of the resistor is depicted by special stripes, or Roman symbols on the graphic image of the case, depending on the power (0.125 W – two oblique lines “//”, 0.25 – one oblique line “/”, 0.5 – one line along the resistor “ -“, 1W – one transverse line “I”, 2W – two transverse lines “II”, 5W – tick “V”, 7W – tick and two transverse lines “VII”, 10W – crosshair “X”, etc. .). The Americans have a zigzag designation for the resistor, as shown in the figure.
	Variable resistor	A resistor whose resistance at its central terminal is adjusted using a “knob.” The nominal resistance indicated in the diagram is the total resistance of the resistor between its extreme terminals, which is not adjustable. Variable resistors can be paired (2 on one regulator)
	Trimmer resistor	A resistor, the resistance of which at its central terminal is adjusted using a “regulator slot” - a hole for a screwdriver. Like a variable resistor, the nominal resistance shown in the diagram is the total resistance of the resistor between its outer terminals, which is not adjustable
	Thermistor	A semiconductor resistor whose resistance changes depending on the ambient temperature. As the temperature increases, the resistance of the thermistor decreases, and as the temperature decreases, on the contrary, it increases. It is used to measure temperature as a temperature sensor, in thermal stabilization circuits of various equipment cascades, etc.
	Photoresistor	A resistor whose resistance changes depending on the light level. As the illumination increases, the resistance of the thermistor decreases, and when the illumination decreases, on the contrary, it increases. Used for measuring illumination, recording light fluctuations, etc. A typical example is the “light barrier” of a turnstile. Recently, instead of photoresistors, photodiodes and phototransistors are more often used
	Varistor	A semiconductor resistor that sharply reduces its resistance when the voltage applied to it reaches a certain threshold. Varistor is designed to protect electrical circuits and radio devices from random voltage surges
	Capacitor	An element of a radio circuit that has an electrical capacitance and is capable of accumulating an electrical charge on its plates. The application is varied depending on the size of the capacitance; the most common radio element after the resistor
		A capacitor, in the manufacture of which an electrolyte is used, due to this, with a relatively small size, has a much larger capacity than an ordinary “non-polar” capacitor. When using it, polarity must be observed, otherwise the electrolytic capacitor loses its storage properties. Used in power filters, as pass-through and storage capacitors for low-frequency and pulse equipment. A conventional electrolytic capacitor self-discharges in no more than a minute, has the property of “losing” capacity due to the drying out of the electrolyte; to eliminate the effects of self-discharge and loss of capacity, more expensive capacitors are used - tantalum
		A capacitor whose capacity is adjusted using a “regulator slot” - a hole for a screwdriver. Used in high frequency circuits of radio equipment
		A capacitor whose capacity is adjusted using a handle (steering wheel) located outside the radio receiver. Used in high-frequency circuits of radio equipment as an element of a selective circuit that changes the tuning frequency of a radio transmitter or radio receiver
		A high-frequency device that has resonant properties similar to an oscillatory circuit, but at a certain fixed frequency. Can be used at “harmonics” - frequencies that are multiples of the resonant frequency indicated on the device body. Often, quartz glass is used as a resonating element, so the resonator is called a “quartz resonator”, or simply “quartz”. It is used in generators of harmonic (sinusoidal) signals, clock generators, narrow-band frequency filters, etc.
		Winding (coil) made of copper wire. It can be frameless, on a frame, or can be made using a magnetic core (a core made of magnetic material). Has the property of storing energy due to magnetic field. Used as an element of high-frequency circuits, frequency filters and even the antenna of a receiving device
		A coil with adjustable inductance, which has a movable core made of magnetic (ferromagnetic) material. As a rule, it swings on a cylindrical frame. Using a non-magnetic screwdriver, the depth of immersion of the core into the center of the coil is adjusted, thereby changing its inductance
		An inductor containing a large number of turns, which is made using a magnetic circuit (core). Like a high-frequency inductor, the inductor has the property of storing energy. Used as low-pass filter elements audio frequency, power supply and pulse accumulation filter circuits
		An inductive element consisting of two or more windings. An alternating (changing) electric current applied to the primary winding causes a magnetic field to appear in the transformer core, which in turn induces magnetic induction in the secondary winding. As a result, an electric current appears at the output of the secondary winding. The dots on the graphic symbol at the edges of the transformer windings indicate the beginnings of these windings, Roman numerals indicate the winding numbers (primary, secondary)
		A semiconductor device capable of passing current in one direction but not in the other. The direction of the current can be determined by a schematic diagram - converging lines, like an arrow, indicate the direction of the current. The anode and cathode terminals are not indicated by letters in the diagram.
		A special semiconductor diode designed to stabilize the voltage of reverse polarity applied to its terminals (for a stabistor - straight polarity)
		A special semiconductor diode that has an internal capacitance and changes its value depending on the amplitude of the reverse polarity voltage applied to its terminals. It is used to generate a frequency-modulated radio signal in circuits for electronic regulation of the frequency characteristics of radio receivers
		A special semiconductor diode, the crystal of which glows under the influence of an applied direct current. Used as a signal element for the presence of electric current in a certain circuit. Comes in different glow colors
		A special semiconductor diode, when illuminated, a weak electric current appears at the terminals. Used for measuring illumination, recording light fluctuations, etc., similar to a photoresistor
		A semiconductor device designed to switch an electrical circuit. When a small positive voltage is applied to the control electrode relative to the cathode, the thyristor opens and conducts current in one direction (like a diode). The thyristor closes only after the current flowing from the anode to the cathode disappears, or the polarity of this current changes. The terminals of the anode, cathode and control electrode are not indicated by letters in the diagram
		A composite thyristor capable of switching currents of both positive polarity (from anode to cathode) and negative (from cathode to anode). Like a thyristor, a triac closes only after the current flowing from the anode to the cathode disappears, or the polarity of this current changes
		A type of thyristor that opens (starts passing current) only when a certain voltage is reached between its anode and cathode, and closes (stops passing current) only when the current decreases to zero, or the polarity of the current changes. Used in pulse control circuits
		A bipolar transistor, which is controlled by a positive potential at the base relative to the emitter (the arrow at the emitter shows the conditional direction of the current). Moreover, when the base-emitter input voltage increases from zero to 0.5 volts, the transistor is in the closed state. After further increasing the voltage from 0.5 to 0.8 volts, the transistor operates as an amplification device. At the final section of the “linear characteristic” (about 0.8 volts), the transistor is saturated (fully open). A further increase in the voltage at the base of the transistor is dangerous; the transistor may fail (a sharp increase in the base current occurs). According to the textbooks, a bipolar transistor is controlled by a base-emitter current. Direction of switched current in npn transistor– from collector to emitter. The base, emitter and collector terminals are not indicated by letters in the diagram
		A bipolar transistor, which is controlled by a negative potential at the base relative to the emitter (the arrow at the emitter shows the conditional direction of the current). According to the textbooks, a bipolar transistor is controlled by a base-emitter current. The direction of the switched current in a pnp transistor is from the emitter to the collector. The base, emitter and collector terminals are not indicated by letters in the diagram
		A transistor (usually n-p-n), the resistance of the collector-emitter junction of which decreases when it is illuminated. The higher the illumination, the lower the junction resistance. Used for measuring illumination, recording light fluctuations (light pulses), etc., similar to a photoresistor
		A transistor whose drain-source junction resistance decreases when voltage is applied to its gate relative to the source. It has a high input resistance, which increases the sensitivity of the transistor to low input currents. Has electrodes: Gate, Source, Drain and Substrate (not always the case). The principle of operation can be compared to a water tap. The greater the voltage on the gate (the greater the angle the valve handle is turned), the greater the current (more water) flows between the source and drain. Compared to a bipolar transistor, it has a larger range of regulating voltage - from zero to tens of volts. The gate, source, drain and substrate terminals are not indicated by letters in the diagram
		A field-effect transistor controlled by a positive gate potential relative to the source. Has an insulated shutter. It has a high input resistance and a very low output resistance, which allows small input currents to control large output currents. Most often, the substrate is technologically connected to the source
		A field-effect transistor controlled by a negative potential at the gate relative to the source (for remembering, the p-channel is positive). Has an insulated shutter. It has a high input resistance and a very low output resistance, which allows small input currents to control large output currents. Most often, the substrate is technologically connected to the source
		A field-effect transistor that has the same properties as “with a built-in n-channel” with the difference that it has an even higher input resistance. Most often, the substrate is technologically connected to the source. Using insulated gate technology, MOSFET transistors are made, controlled by an input voltage from 3 to 12 volts (depending on the type), having an open drain-source junction resistance from 0.1 to 0.001 Ohm (depending on the type)
		A field-effect transistor that has the same properties as “with a built-in p-channel” with the difference that it has an even higher input resistance. Most often, the substrate is technologically connected to the source

– electronic components assembled into analog and digital devices: TVs, measuring instruments, smartphones, computers, laptops, tablets. If previously parts were depicted close to their natural appearance, today conventional graphic symbols of radio components on the diagram, developed and approved by the International Electrotechnical Commission, are used.

Types of Electronic Circuits

In radio electronics, there are several types of circuits: circuit diagrams, wiring diagrams, block diagrams, voltage and resistance maps.

Schematic diagrams

Such an electrical diagram gives a complete picture of all the functional components of the circuit, the types of connections between them, and the operating principle of electrical equipment. Circuit diagrams are commonly used in distribution networks. They are divided into two types:

Single-line. This drawing shows only power circuits.
Full. If the electrical installation is simple, then all its elements can be displayed on one sheet. To describe equipment that contains several circuits (power, measuring, control), drawings are made for each unit and placed on different sheets.

Block diagrams

In radio electronics, a block is an independent part of an electronic device. A block is a general concept; it can include both a small and a significant number of parts. A block diagram (or block diagram) provides only general concept about the design of an electronic device. It does not display: the exact composition of the blocks, the number of ranges of their functioning, the schemes according to which they are assembled. In a block diagram, blocks are represented by squares or circles, and the connections between them are represented by one or two lines. The directions of signal passage are indicated by arrows. The names of the blocks in full or abbreviated form can be applied directly to the diagram. The second option is to number the blocks and decipher these numbers in a table located in the margins of the drawing. Graphic images of blocks can display the main parts or plot their operation.

Assembly

Wiring diagrams are convenient for creating an electrical circuit yourself. They indicate the location of each circuit element, communication methods, and the laying of connecting wires. The designation of radioelements on such diagrams usually approaches their natural appearance.

Voltage and resistance maps

A stress map (diagram) is a drawing in which, next to the individual parts and their terminals, the voltage values characteristic of the normal operation device. Voltages are placed in the gaps of the arrows, showing in which places measurements need to be made. The resistance map indicates the resistance values characteristic of a working device and circuits.

How are various radio components indicated in the diagrams?

As previously mentioned, there is a specific graphic symbol to designate radio components of each type.

Resistors

These parts are designed to regulate the current in the circuit. Fixed resistors have a certain and constant resistance value. For variables, the resistance ranges from zero to the set maximum value. The names and symbols of these radio components in the diagram are regulated by GOST 2.728-74 ESKD. In general, in the drawing they represent a rectangle with two terminals. American manufacturers designate resistors on diagrams with a zigzag line. image of resistors on diagrams

image of resistors on circuit diagrams

Fixed resistors

Characterized by resistance and power. They are indicated by a rectangle with lines indicating a specific power value. Exceeding the specified value will lead to failure of the part. The diagram also indicates: the letter R (resistor), a number indicating the serial number of the part in the circuit, and the resistance value. These radio components are designated by numbers and letters - “K” and “M”. The letter “K” means kOhm, “M” means mOhm.

Variable resistors

image of variable resistors on diagrams. Their design includes a moving contact, which changes the value of resistance. The part is used as a control element in audio and other similar equipment. In the diagram it is indicated by a rectangle indicating fixed and moving contacts. The drawing shows a constant nominal resistance. There are several options for connecting resistors:

resistor connection options

Consistent. The end lead of one part is connected to the start lead of the other. A common current flows through all elements of the circuit. Connecting each subsequent resistor increases the resistance.
Parallel. The initial terminals of all resistances are connected at one point, the final terminals at another. Current flows through each resistor. The total resistance in such a circuit is always less than the resistance of an individual resistor.
Mixed. This is the most popular type of connection of parts, combining the two described above.

Capacitors

graphical representation of capacitors in diagrams A capacitor is a radio component consisting of two plates separated by a dielectric layer. It is applied to the diagram in the form of two lines (or rectangles for electrolytic capacitors) indicating the plates. The gap between them is a dielectric layer. Capacitors are second only to resistors in terms of popularity in circuits. Capable of accumulating an electrical charge with subsequent release.

Capacitors with constant capacitance. The letter “C”, the serial number of the part, and the value of the nominal capacity are placed next to the icon.
With variable capacity. The minimum and maximum capacity values are indicated next to the graphic icon.

In circuits with high voltage in capacitors, with the exception of electrolytic ones, the voltage value is indicated after the capacitance. When connecting electrolytic capacitors, polarity must be observed. To indicate a positively charged plate, use the “+” sign or a narrow rectangle. If there is no polarity, both plates are indicated by narrow rectangles. Electrolytic capacitors are installed in power supply filters for low-frequency and pulsed devices.

Diodes and Zener diodes

graphic representation of diodes and zener diodes on diagrams A diode is a semiconductor device designed to pass electric current in one direction and create obstacles to its flow in the opposite direction. This radio element is designated in the form of a triangle (anode), the top of which is directed in the direction of current flow. A line (cathode) is placed in front of the vertex of the triangle. A zener diode is a type of semiconductor diode. Stabilizes the voltage of reverse polarity applied to the terminals. A stabistor is a diode to the terminals of which a voltage of direct polarity is applied.

Transistors

Transistors are semiconductor devices used to generate, amplify and convert electrical oscillations. With their help, they control and regulate the voltage in the circuit. They differ in a variety of designs, frequency ranges, shapes and sizes. The most popular are bipolar transistors, designated in diagrams by the letters VT. They are characterized by the same electrical conductivity of the collector and emitter.

graphic representation of transistors on circuits

Microcircuits

Microcircuits are complex electronic components. They are a semiconductor substrate into which resistors, capacitors, diodes and other radio components are integrated. They are used to convert electrical pulses into digital, analog, analog-digital signals. Available with or without housing. The rules for conventional graphic designation (UGO) of digital and microprocessor microcircuits are regulated by GOST 2.743-91 ESKD. According to them, the UGO has the shape of a rectangle. The diagram shows the supply lines to it. The rectangle consists of only the main field or the main one and two additional ones. The main field must indicate the functions performed by the element. Additional fields usually decipher the pin assignments. Primary and secondary fields may or may not be separated by a solid line.

graphic representation of microcircuits

Buttons, relays, switches

graphic representation of buttons and switches on a diagram

relay image on diagrams

Letter designation of radio components on the diagram

Letter codes of radioelements on circuit diagrams

Devices and elements	Letter code
Devices: amplifiers, remote control devices, lasers, masers; general designation	A
Converters of non-electrical quantities into electrical ones (except for generators and power supplies) or vice versa, analogue or multi-digit converters, sensors for indicating or measuring; general designation	IN
Speaker	VA
Magnetostrictive element	BB
Ionizing radiation detector	BD
Selsyn sensor	Sun
Selsyn receiver	BE
Telephone (capsule)	B.F.
Thermal sensor	VC
Photocell	B.L.
Microphone	VM
Pressure meter	VR
Piezo element	IN
Speed sensor, tachogenerator	BR
Pickup	B.S.
Speed sensor	VV
Capacitors	WITH
Integrated circuits, microassemblies: general designation	D
Integrated analog microcircuit	D.A.
Integrated digital microcircuit, logical element	DD
Information storage device (memory)	D.S.
Delay device	D.T.
Various elements: general designation	E
Lighting lamp	EL
A heating element	EC
Arresters, fuses, protection devices: general designation	F
fuse	F.U.
Generators, power supplies, crystal oscillators: general designation	G
Battery of galvanic cells, batteries	G.B.
Indicating and signaling devices; general designation	N
Sound alarm device	ON
Symbolic indicator	HG
Light signaling device	H.L.
Relays, contactors, starters; general designation	TO
Electrothermal relay	kk
Time relay	CT
Contactor, magnetic starter	km
Inductors, chokes; general designation	L
Engines, general designation	M
Measuring instruments; general designation	R
Ammeter (milliammeter, microammeter)	RA
Pulse counter	PC
Frequency meter	PF
Ohmmeter	PR
Recording device	PS
Action time meter, clock	RT
Voltmeter	PV
Wattmeter	PW
Resistors are constant and variable; general designation	R
Thermistor	RK
Measuring shunt	R.S.
Varistor	RU
Switches, disconnectors, short circuits in power circuits (in equipment power supply circuits); general designation	Q
Switching devices in control, signaling and measuring circuits; general designation	S
Switch or switch	S.A.
Push-button switch	S.B.
Automatic switch	SF
Transformers, autotransformers; general designation	T
Electromagnetic stabilizer	T.S.
Converters of electrical quantities into electrical ones, communication devices; general designation	And
Modulator	ive
Demodulator	UR
Discriminator	Ul
Frequency converter, inverter, frequency generator, rectifier	UZ
Semiconductor and electrovacuum devices; general designation	V
Diode, zener diode	VD
Transistor	VT
Thyristor	VS
Electrovacuum device	VL
Microwave lines and elements; general designation	W
Coupler	WE
Koro tkoea we ka tel	W.K.
Valve	W.S.
Transformer, phase shifter, heterogeneity	W.T.
Attenuator	W.U.
Antenna	W.A.
Contact connections; general designation	X
Pin (plug)	XP
Socket (socket)	XS
Demountable connection	XT
High frequency connector	XW
Mechanical devices with electromagnetic drive; general designation	Y
Electromagnet	YA
Electromagnetic brake	YB
Electromagnetic clutch	YC
Terminal devices, filters; general designation	Z
Limiter	ZL
Quartz filter	ZQ

Letter codes of the functional purpose of a radio-electronic device or element

Functional purpose of the device, element	Letter code
Auxiliary	A
Counting	WITH
Differentiating	D
Protective	F
Test	G
Signal	N
Integrating	1
Gpavny	M
Measuring	N
Proportional	R
State (start, stop, limit)	Q
Return, reset	R
Memorizing, recording	S
Synchronizing, delaying	T
Speed (acceleration, braking)	V
Summing	W
Multiplication	X
Analog	Y
Digital	Z

Letter abbreviations for radio electronics

Letter abbreviation	Decoding the abbreviation
A.M.	amplitude modulation
AFC	automatic frequency adjustment
APCG	automatic local oscillator frequency adjustment
APChF	automatic frequency and phase adjustment
AGC	automatic gain control
ARYA	automatic brightness adjustment
AC	acoustic system
AFU	antenna-feeder device
ADC	analog-to-digital converter
frequency response	amplitude-frequency response
BGIMS	large hybrid integrated circuit
NOS	wireless remote control
BIS	large integrated circuit
BOS	signal processing unit
BP	power unit
BR	scanner
DBK	radio channel block
BS	information block
BTK	blocking transformer personnel
BTS	blocking transformer line
BOO	Control block
BC	chroma block
BCI	integrated color block (using microcircuits)
VD	video detector
VIM	time-pulse modulation
VU	video amplifier; input (output) device
HF	high frequency
G	heterodyne
GW	playback head
GHF	high frequency generator
GHF	hyper high frequency
GZ	start generator; recording head
GIR	heterodyne resonance indicator
GIS	hybrid integrated circuit
GKR	frame generator
GKCH	sweep generator
GMW	meter wave generator
GPA	smooth range generator
GO	envelope generator
HS	signal generator
GSR	line scan generator
gss	standard signal generator
yy	clock generator
GU	universal head
VCO	voltage controlled generator
D	detector
dv	long waves
dd	fractional detector
days	voltage divider
dm	power divider
DMV	decimeter waves
DU	remote control
DShPF	dynamic noise reduction filter
EASC	unified automated communication network
ESKD	unified system of design documentation
zg	audio frequency generator; master oscillator
zs	slowing system; sound signal; pickup
AF	audio frequency
AND	integrator
ICM	pulse code modulation
ICU	quasi-peak level meter
ims	integrated circuit
ini	linear distortion meter
inch	infra-low frequency
and he	reference voltage source
SP	power supply
ichh	frequency response meter
To	switch
KBV	traveling wave coefficient
HF	short waves
kWh	extremely high frequency
KZV	recording-playback channel
CMM	pulse code modulation
kk	frame deflection coils
km	coding matrix
cnc	extremely low frequency
efficiency	efficiency
KS	deflection system line coils
ksv	standing wave ratio
ksvn	voltage standing wave ratio
CT	check Point
KF	focusing coil
TWT	traveling wave lamp
lz	delay line
fishing	back wave lamp
LPD	avalanche diode
lppt	tube-semiconductor TV
m	modulator
M.A.	magnetic antenna
M.B.	meter waves
TIR	metal-insulator-semiconductor structure
MOP	metal-oxide-semiconductor structure
ms	chip
MU	microphone amplifier
neither	nonlinear distortion
LF	low frequency
ABOUT	common base (switching on a transistor according to a circuit with a common base)
VHF	very high frequency
oi	common source (turning on the transistor *according to a circuit with a common source)
OK	common collector (switching on a transistor according to a circuit with a common collector)
onch	very low frequency
oos	negative feedback
OS	deflection system
OU	operational amplifier
OE	common emitter (connecting a transistor according to a circuit with a common emitter)
Surfactant	surface acoustic waves
pds	two-speech set-top box
Remote control	remote control
pcn	code-voltage converter
pnc	voltage-to-code converter
PNC	converter voltage frequency
village	positive feedback
PPU	noise suppressor
pch	intermediate frequency; frequency converter
ptk	tv channel switch
PTS	full TV signal
Vocational school	industrial television installation
PU	preliminary effort
PUV	playback pre-amplifier
PUZ	recording pre-amplifier
PF	bandpass filter; piezo filter
ph	transfer characteristic
pcts	full color television signal
Radar	line linearity regulator; radar station
RP	memory register
RPCHG	manual adjustment of local oscillator frequency
RRS	line size control
PC	shift register; mixing regulator
RF	notch or stop filter
REA	radio-electronic equipment
SBDU	wireless remote control system
VLSI	ultra-large scale integrated circuit
NE	medium waves
SVP	touch program selection
Microwave	ultra high frequency
sg	signal generator
SDV	ultralong waves
SDU	dynamic light installation; remote control system
SK	channel selector
SLE	all-wave channel selector
sk-d	UHF channel selector
SK-M	meter wave channel selector
CM	mixer
ench	ultra-low frequency
JV	grid field signal
ss	clock signal
ssi	horizontal clock pulse
SU	selector amplifier
sch	average frequency
TV	tropospheric radio waves; TV
TVS	line output transformer
tvz	audio output channel transformer
tvk	output frame transformer
TIT	television test chart
TKE	temperature coefficient of capacitance
tka	temperature coefficient of inductance
tkmp	temperature coefficient of initial magnetic permeability
tkns	temperature coefficient of stabilization voltage
tks	temperature coefficient of resistance
ts	network transformer
shopping center	television center
tsp	color bar table
THAT	technical specifications
U	amplifier
UV	playback amplifier
UVS	video amplifier
UVH	sample-hold device
UHF	high frequency signal amplifier
UHF	UHF
UZ	recording amplifier
Ultrasound	audio amplifier
VHF	ultrashort waves
ULPT	unified tube-semiconductor TV
ULLTST	unified lamp-semiconductor color TV
ULT	unified tube TV
UMZCH	audio power amplifier
CNT	unified TV
ULF	low frequency signal amplifier
UNU	voltage controlled amplifier.
UPT	DC amplifier; unified semiconductor TV
HRC	intermediate frequency signal amplifier
UPCHZ	intermediate frequency signal amplifier?
UPCH	intermediate frequency image amplifier
URCH	radio frequency signal amplifier
US	interface device; comparison device
USHF	microwave signal amplifier
USS	horizontal sync amplifier
USU	universal touch device
UU	control device (node)
UE	accelerating (control) electrode
UEIT	universal electronic test chart
PLL	phase automatic frequency control
HPF	high pass filter
FD	phase detector; photodiode
FIM	pulse phase modulation
FM	phase modulation
LPF	low pass filter
FPF	intermediate frequency filter
FPCHZ	audio intermediate frequency filter
FPCH	image intermediate frequency filter
FSI	lumped selectivity filter
FSS	concentrated selection filter
FT	phototransistor
FCHH	phase-frequency response
DAC	digital-to-analog converter
Digital computer	digital computer
CMU	color and music installation
DH	central television
BH	frequency detector
CHIM	pulse frequency modulation
world championship	frequency modulation
shim	pulse width modulation
shs	noise signal
ev	electron volt (e V)
COMPUTER.	electronic computer
emf	electromotive force
ek	electronic switch
CRT	cathode-ray tube
AMY	electronic musical instrument
emos	electromechanical feedback
EMF	electromechanical filter
EPU	record player
Digital computer	electronic digital computer