April 16, 2025 Rufina Uche

Joint Army-Navy Nomenclature System

If you've ever come across military equipment labeled AN/PRC-152 or OK-105/GRC, you’ve encountered the Joint Electronics Type Designation System (JETDS)—a standardized naming convention used by the U.S. military. Established during World War II, JETDS ensures that every piece of electronic equipment has a structured, recognizable name, allowing seamless communication between military branches and allies.

Formerly called the Joint Army-Navy Nomenclature System, the JETDS assigns standardized, unclassified names to electronic devices. Officially formalized in 1957 under MIL-STD-196, this system helps streamline communication and logistics in the military's electronic operations. But its complexity leaves many scratching their heads.

But what do these cryptic codes actually mean? Let’s break them down.

Application of JETDS

JETDS covers a vast range of military electronics, from handheld radios to complex missile guidance systems. Here’s a general list of what falls under this system:

Data processing systems
Detection and tracking devices (for air, land, and underwater operations)
Recognition and identification systems
Communications equipment
Navigation systems
Weapons control and evaluation systems
Flight control systems
Electronic countermeasures

What JETDS Doesn't Cover

While comprehensive, JETDS does not apply to:

Software programs
Unmodified commercial electronics (which retain their original manufacturer designations)

Additionally, JETDS operates independently of the Army’s "M" designation system (e.g., M4 carbine rifle), which covers broader equipment categories.

Breaking Down the JETDS Hierarchy

JETDS isn’t just a string of random letters and numbers—each part of a designation follows a structured format to indicate the function and classification of the equipment.

Item Levels Explained

Level	Description	Example
Unit	A standalone item that may require additional components to function.	A handheld radio or an antenna.
Group	A set of related units that work together but don’t function independently.	"Antenna Group"
Set	A unit or group combined with accessories for a specific function.	"Radio Terminal Set"
Subsystem	A collection of sets and groups forming part of a larger system.	Guided missile subsystem.
System	A fully integrated setup designed for a mission-critical task.	"Shipboard Computer System"
Center	A command hub for administrative and operational control.	Military operations center.
Central	A stationary, unified technical facility.	"Communications Central"

This structured approach helps the military efficiently manage, deploy, and maintain equipment.

Deciphering JETDS Type Designations

Every JETDS designation has two primary components:

Type Designation (e.g., AN/PRC-152)
Item Name (e.g., "Radio Set, Portable")

The Type Designation follows a fixed format:

Understanding the Code: AN/PRC-152

AN/ → Stands for "Army-Navy", signifying joint usage.
First Letter (Installation Platform):

A = Piloted Aircraft
B = Underwater Mobile/Submarine
C = Cryptographic
D = Pilotless Aircraft/Carrier
F = Fixed Ground
G = General Ground Use
K = Amphibious
M = Mobile (Ground)
P = Portable
S = Water
T = Transportable (Ground)
U = General Utility (Multiple)
V = Vehicular (Ground)
W = Water Surface and Underwater Combined
Z = Piloted-Pilotless Airborne Vehicles Combined

Second Letter (Equipment Type):

A = Invisible Light, Heat Radiation
B = Communications Security
C = Carrier – Electronic Wave/Signal
D = Radiac
E = Laser
F = Fiber Optics
G = Telegraph/Teletype
I = Interphone and Public Access
J = Electromechanical or Inertial Wire Covered
K = Telemetering
L = Countermeasures
M = Meteorological
N = Sound in Air
P = Radar
Q = Sonar/Underwater Sound
R = Radio
S = Special or Combination
T = Telephone (Wire)
V = Visual/Visible Light
W = Armament (peculiar to armament not otherwise covered)
X = Facsimile to Television
Y = Data Processing or Computer
Z = Communications

Third Letter (Purpose):

A = Auxiliary Assembly
B = Bombing
C = Communications Receiving/Transmitting
D = Direction Finder/Reconnaissance/Surveillance
E = Ejection and/or Release
G = Fire Control or Search Light Directing
H = Recording/Reproducing
K = Computing
M = Maintenance/Test Assemblies
N = Navigational Aids
Q = Special or Combination
R – Receiving/Passive Detecting
S = Detecting/Range and Bearing Search
T = Transmitting
W = Automatic Flight or Remote Control
X = Identification and Recognition
Y = Surveillance (Search, Detect, and Multiple Target Tracking) and Control (Fire and Air Control)
X = Secure

So, AN/PRC-152 translates to a Portable Radio Communications device. The 152 at the end is simply the series number.

Additional Modifiers:

Modification Letters (A, B, C, etc.) → Indicate different versions of the same equipment.
(V) → Denotes variable models or configurations.
(C) → Indicates cryptographic capabilities.
-Tn → Represents training equipment.

For example, AN/PRC-77(V) indicates a variant of a portable radio communications system.

Group and Unit Designations in JETDS

Example of Group Designations

Group designators typically start with a two-letter code, followed by a number and a slash indicating the associated system.

Group Indicator	Family Name	Examples (does not limit the application of group indicators)
OA	Miscellaneous groups	Groups not listed
OB	Multiplexer and/or demultiplexer groups	All types
OD	Indicator groups	All types
OE	Antenna groups	All types
OF	Adapter groups	All types
OG	Amplifier groups	All types
OH	Simulator groups	All types
OI	Cryptographic groups	All types
OJ	Consoles and Console groups	All types
OK	Control groups	All types
OL	Data analysis and Data processing groups	All types
OM	Modulator and/or Demodulator groups	All types
ON	Interconnecting groups	All types
OP	Power Supply groups	All non-rotating types
OQ	Test-Set groups	All types
OR	Receiver groups	All types
OS	Satellite groups	All types
OT	Transmitter groups	All types
OU	Converter groups	All types
OV	Generator groups	All types including power generating equipment
OW	Terminal groups	Telegraphs, radios, telephones, etc.
OX	Coder, Recorder, Interrogator, Transponder groups	All types
OY	Radar groups	Do not use if more specific indicator applies
OZ	Radio groups	Do not use if a more specific indicator (OE, OR, OT, etc.) applies

Example: OK-105/GRC

OK = Control group
105 = Model number
GRC = Used with ground radio communication systems

Example of Unit Designations

Unit designators follow a similar format but focus on the primary function of the equipment.

Unit Indicator	Family Name	Examples (does not limit the application of unit indicators)
AB	Support for antennas	Antenna mounts, mast bases, mast sections, towers, etc.
AM	Amplifiers	Power, audio, interphone, radio frequency, video, electronic control, etc.
AS	Antennas, simple and complex	Arrays, parabolic type, masthead whip or telescopic loop, dipole, reflector, etc.
BA	Batteries, primary (non-rechargeable) type	Batteries, battery packs, etc.
BB	Batteries, secondary (rechargeable) type	Batteries, battery packs, etc.
BZ	Alarm units	All types
C	Controls	Control boxes, remote tuning controls, etc.
CA	Computer auxiliary units	Input/Output, peripherals, 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	Mechanical and/or electronic mathematical calculating devices
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 of RF and non-RF conductors
CY	Cases and cabinets	Rigid and semi-rigid structures for enclosing or carrying equipment
D	Dispensers	Chaff
DA	Loads, dummy	RF and non-RF test loads
DI	Data transmission units	Devices for authentication and transferring recorded or generated data over transmitter/receiver links
DT	Detecting heads	Magnetic, capacitive, or optical pickup devices, search coils, hydrophones, etc.
DU	Display Units/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 communications, etc.
FR	Frequency measuring devices	Frequency meters, tuned cavity, etc.
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 earphones
HD	Environmental apparatus	Heating, cooling, dehumidifying, pressure, vacuum devices, etc.
ID	Indiciator 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 generators	Units generating a pseudorandom sequence of crypto variables using algorithms
KY	Keying devices	Mechanical, electrical, and electronic key coders, interrupters, etc.
LA	Lasers	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	Multimeters, vacuum tube voltmeters, power meters, volt-ohm-milliameters, 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	Communications, 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 oscilloscopes, 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	Mechanisms 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 transceivers, composites of transmitter and receiver, etc.
S	Shelter	Protective shelters, etc.
SA	Switching units	Manual, impact, motor-driven, pressure-operated, electronic, etc.
SB	Switchboards	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, scopes, 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	Sonar transducers, vibration pickups, etc. (see H, LS, and M)
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.

Example: R-2348/PRC

R = Radio receiver
2348 = Model number
PRC = Portable radio communication

Every designation serves as a mini blueprint, instantly conveying function, usage, and compatibility.

A Brief History of JETDS

JETDS was introduced during World War II to create a unified equipment naming system across military branches. Over the decades, it expanded to include modern technologies and allied nations.

Key Milestones

1943 – System adopted.
1957 – Formalized under MIL-STD-196.
2018 – Latest revision (MIL-STD-196G).

Despite the rise of advanced technologies, JETDS remains a critical organizational tool in military logistics.

Why JETDS Matters

JETDS isn’t just an internal military code—it plays a crucial role in:
✔ Streamlining logistics by ensuring every piece of equipment has a unique, standardized identifier.
✔ Enhancing interoperability across military branches and allied nations.
✔ Facilitating equipment tracking for maintenance, deployment, and upgrades.

For military enthusiasts and tech geeks, decoding JETDS is like solving a puzzle that reveals the complexity and precision behind military operations.

"Part of" vs. "Used With"—Understanding Equipment Relationships

JETDS also distinguishes between:

"Part of" → Essential components that come included with the system (e.g., a receiver inside a radio).
"Used with" → Accessories or add-ons that enhance a system but are not essential (e.g., a headset for a radio).

Understanding these classifications helps the military track inventory, dependencies, and replacements efficiently.

JETDS Beyond the U.S.

Other nations have adopted similar nomenclature systems:

Japan → Uses "J/" instead of "AN/".
Taiwan (Republic of China) → Uses "CS/".

While the naming formats may be similar, the equipment itself may have different specifications and capabilities.

Conclusion

Whether you’re piecing together AN/PRC-77, navigating MIL-STD-196, or simply curious about military logistics, understanding JETDS provides a fascinating look into defense technology.