| Table of Unit Indicators |
| Unit indicators |
Family name |
Examples of use |
| AB |
Support for antennas |
Antenna mounts, mast bases, mast sections, towers, etc. |
| AM |
Amplifiers |
Power, audio, interphone, radio frequency, video, electronic control, etc. |
| AS |
Antenna, simple and complex |
Arrays, parabolic type, masthead whip or telescopic loop, dipole, reflector, etc. |
| BA |
Battery, primary type |
Batteries, battery packs, etc. |
| BB |
Battery, secondary type |
Batteries, battery packs, etc. |
| BZ |
Alarm units |
All types |
| C |
Controls |
Control box, remote tuning control, etc. |
| CA |
Computers auxiliary units |
Input/output peripheral, etc. |
| CC |
Cable assemblies, RF |
RF cables, waveguides, transmission lines, etc., with terminals |
| CD |
Controlling devices |
Complex controlling devices |
| CM |
Comparators |
Compares two or more input signals |
| CN |
Compensators |
Electrical and/or mechanical compensating, regulating or attenuating apparatus |
| CP |
Computers |
A mechanical and/or electronic mathematical calculating device |
| CU |
Couplers |
Impedance coupling devices, directional couplers, etc. |
| CV |
Converters (electronic) |
Electronic apparatus for changing the phase frequency, or from one medium to another |
| CW |
Radomes |
Radomes |
| CX |
Cable assemblies, non RF |
Non RF cables with terminals, test leads, also composite cables or RF and non RF conductors |
| CY |
Cases and cabinets |
Rigid and semirigid structure for enclosing or carrying equipment |
| D |
Dispensers |
Chaff |
| DA |
Loads, dummy |
RF and non RF test loads |
| DI |
Data transmission |
Devices for authentication and transferring recorded or generated data over transmitter/receiver links. |
| DT |
Detecting heads |
Magnetic, capacitive or optical pickup devices, search coil, hydrophones, etc. |
| DU |
Display unit/monitors |
All types that are external devices for computers, test sets, etc. |
| F |
Filter units |
Electronic types, back-pass, low pass, band suppression, noise telephone, filter networks; excludes non-repairable types |
| FO |
Fiber optics |
Electrical, electronic and communication |
| FR |
Frequency measuring device |
Frequency meters, tuned cavity |
| G |
Generators, power |
Electrical power generators without prime movers (see PU) |
| GO |
Goniometers |
Instruments for measuring angles for determination of energy transferred from moving to fixed coil (directional) antennas, etc. |
| H |
Head, hand and chest sets |
Includes earphone |
| HD |
Environmental Apparatus |
Heating, cooling, dehumidifying, pressure, vacuum devices, etc. |
| ID |
Indicator units, non-cathode ray tube |
Calibrated dials and meters, indicating lights, etc. (see also IP) |
| IM |
Intensity measuring devices |
Includes SWR gear, field intensity noise meters, slotted lines, etc. |
| IP |
Indicator units, cathode ray tube |
Azimuth, elevation, panoramic, etc. |
| J |
Interface units |
Interconnecting and junction units, etc. Do not use if a more specific indicator applies. |
| KG |
Key generator |
Units generating a pseudorandom sequence of cryptovariables using algorithms |
| KY |
Keying devices |
Mechanical, electrical and electronic key coders, interrupters, etc. |
| LA |
Laser |
Communication, electrical, etc. |
| LS |
Loudspeakers |
Separately housed loudspeakers and intercommunication stations |
| M |
Microphones |
Radio, telephone, throat, hand, etc. |
| MD |
Modulators, demodulators, discriminators |
Devices for varying amplitude, frequency or phase |
| ME |
Meters |
Multimeter, vacuum tube voltmeters, power meters, volt-ohm-millimeters, etc. |
| MK |
Miscellaneous kits |
Maintenance, modification, etc. |
| ML |
Meteorological devices |
Miscellaneous meteorological equipment, etc. |
| MO |
Multipurpose |
Units that perform two or more functions |
| MT |
Mountings |
Mountings, racks, frames, stands, etc. |
| MU |
Memory units |
Memory units |
| MW |
Microwave |
Communication, etc. |
| MX |
Miscellaneous |
Equipment not otherwise classified. Do not use if a better indicator is available. |
| O |
Oscillators |
Master frequency, blocking, multi-vibrators, etc. (for test oscillators, see SG) |
| OC |
Oceanographic devices |
Bathythermograph, etc. |
| OS |
Oscilloscope, test |
Test oscilloscope for general test purposes (see IP) |
| PL |
Plug-in units |
Plug-in units not otherwise classified |
| PP |
Power supplies |
Non-rotating machine types, such as vibrator pack rectifier, thermoelectric, etc. |
| PT |
Mapping and plotting units |
Electronic types only |
| PU |
Power equipment |
Rotating power equipment, motor-generators, dynamotors, etc. |
| R |
Receivers |
Receivers, all types except telephone |
| RB |
Robotics |
Electric-mechanical, etc. |
| RD |
Recorder-reproducers |
Sound, graphic, tape, wire, film, disc, facsimile, magnetic, mechanical, etc. |
| RE |
Relay assembly units |
Electrical, electronic, etc. |
| RL |
Reeling machines |
Mechanism for dispensing and rewinding antenna or field wire cable, etc. |
| RO |
Recorders |
Sound, graphic, tape, wire, film disc, facsimile, magnetic, mechanical, tape, and card punch, etc. |
| RP |
Reproducers |
Sound, graphic, tape, wire, film, disc, facsimile, magnetic, mechanical, punched tape and card readers, etc. |
| RR |
Reflectors |
Target, confusion, etc., except antenna reflectors (see AS) |
| RT |
Receiver and transmitter |
Radio and radar transceiver, composites of transmitter and receiver, etc. |
| S |
Shelter |
Electrical equipment, etc. |
| SA |
Switching units |
Manual, impact, motor driven, pressure operated, electronic, etc. |
| SB |
Switchboard |
Telephone, fire control, power distribution, etc. |
| SG |
Generator, signal |
Test oscillators, noise generators, etc. (see O) |
| SM |
Simulators |
Flight, aircraft, target, signal, etc. |
| SN |
Synchronizers |
Equipment to coordinate two or more functions |
| SS |
Special purpose |
Devices performing unique functions |
| SU |
Optical units |
Electro-optical units, such as night vision, scope, sights, auto-collimator, viewers, trackers, alignment equipment |
| SY |
Speech, secure |
Devices that secure voice transmission/receiving equipment |
| T |
Transmitters |
Transmitters, all types except telephone |
| TA |
Telephone apparatus |
Miscellaneous telephone equipment |
| TB |
Towed body |
Hydrodynamic enclosures used to house transducers, hydrophones, and other electronic equipment |
| TD |
Timing devices |
Mechanical and electronic timing devices, range devices, multiplexers, electronic gates, etc. |
| TF |
Transformers |
When used as separate units |
| TG |
Positioning devices |
Tilt and/or train assemblies |
| TH |
Telegraph apparatus |
Miscellaneous telegraph items |
| TN |
Tuning units |
Receiver, transmitter, antenna, tuning units, etc. |
| TR |
Transducers |
-- |
| TS |
Test units |
Test and measuring equipment not otherwise classified. Do not use if more specific indicators apply. |
| TT |
Teletypewriter and facsimile apparatus |
Teletype, tape, facsimile miscellaneous equipment |
| TU |
Television |
Special types |
| TW |
Tape units |
Preprogrammed with operational test and checkout data |
| V |
Vehicles |
Carts, dollies, vans peculiar to electronic equipment |
| ZM |
Impedance measuring devices |
Used for measuring Q, C, L, R, or PF, etc. |