PRC-522 military VHF transceiver.

Canadian AN/PRC-522 VHF Transceiver, RT-5121/U.

This is my page about the AN/PRC-522 VHF military transceiver. I don’t have a huge amount of information about these radios which are very similar to the Racal/Thales Panther V and Racal TRA-3900’s that I own. If anyone has any other information about this radio or any of the other similar Racal based radios do let me know so it can be included.

Known features:

AN/PRC-552 IRIS Combat Network Radio

VHF 30 – 108 Mhz 4 watts at 12V DC. Same 12v nicad battery as Racal Cougar system.

20W out when used in Vehicle configuration with VIU (vehicle interface unit).

Designed for voice, data and text messages.

Has 2 different built in cypher systems, one of which is the Vinson cypher (PT on the crypto knob = plain text/clear audio, CT = Cypher Text, CTv = Cypher Text Vinson).

Frequency hopping, 100 hops per second. Wide band or narrow band selectable.


AN/PRC-522 Canadian military VHF transceiver.

These radios are based on the Racal Panther family of EDR/ECCM radios (very similar also to the TRA-3900). Racal designed and developed them back in the very late 80’s early 90’s before being taken over by Thales in 2000. Following their unsuccessful bid based on the very similar TRA-3900 to gain the British army’s contract to replace their ageing clansman radios Thales closed Racal in late 2001.

The PRC-522 has been Canada’s primary combat network manpack radio for almost 2 decades having been purchased in 1991. It is now being upgraded by replacing the cryptographic and data transmission modules (2 out out of the 7 modules in the radio) to increase the data throughput when in the data modes. The 11,000 radios that are in service are then expected to be used for another decade.

PRC-522 internal modules. As you can see it is very similar to the TRA-3900 and Panther.
The power supply PCB is in the rear of the radio, the RF power amplifier is underneath.

One key difference between the PRC-522 and the other similar Racal radios is the location of the backup battery (HUB or Hold Up Battery). Instead of being inside the main body of the radio it is in a separate compartment behind a panel on the rear of the radio. The radio shown in the pictures here appears to be an early Racal development unit. It does not have the Vinson Crypto board and instead is fitted with a Racal designed Crypto Simulator board which has a FPGA and eprom. I believe this is either to allow different Cyphers to be tested or to simulate a radio with Crypto without actually having the very secret Vinson cypher.


CSEC = Cipher Security.

HSET = Hop Set.

TESC = I’m unsure, but a TSEC key is needed for correct hop operation.

Display date = Shift – 9 (toggling the vol control to the “S” position allows you to enter the date/time but the radio I have does not accept the changes.

Blank Display = Shift – 1

Run BIT = Shift – T

Show Mission Configurable Link Codes = T – T

The frequency of Channel 1 (A) can be entered manually once every time the channel switch is turned to channel 1.


  • Select a channel and turn the vol control to HSET.
  • Press Shift (Fr) is displayed and the frequency can be entered.
  • Pressing T allows the entry to be redone.
  • Shift – 0 = INTLEA OF is displayed. Press 1 to set INTLEA ON, Press 0 to set INTLEA OF
  • Shift – 0 = —— 5n (Sn?) is displayed – a 5 digit number can be entered (unknown function)
  • Shift – 0 = 0  0  1  Hc is displayed and a 3 digit hop code can be entered.
  • Shift – 0 = 00000 1L and a frequency can be entered. I believe this is the lower frequency for 1 of 8 bands of barred hop frequencies.
  • Shift  = 00000 1H the upper limit for the barred band – shift steps through the 8 L and H frequencies (my suspicion is to leave as 00000 fo no barred frequencies).

In hop mode: Add = Shift – Shift. Then from ADD, Shift – 1 = ADD, Shift – 0 = BAN, Shift – 3 = SEL

Error tones and Beeps

    • Error Tone.
      • A continuos alternating 2 tone alarm with no pause in between.
        • Incorrect entry during programming.
        • Operation of a hopping net with 2 transceivers set to Master (H).
        • Hopset OTAR reception error.
    • Hailing Tone / Plain Text Cue
      • A series of pips lasting for 10 seconds.
        • Hailing Tone – when operating in Frequency Hopping mode and receiving a Fixed Compatible transmission.
        • Plain Text Cue – In Cipher Text VINSON mode, when receiving a Plain Text message.
    • Advanced Time-Of-Day Warning.
      • A series of pips lasting for 5 seconds and voice can still be heard over the pips.
        • Operation of a hopping net and an outstation sends a transmission with an Advanced TOD, the Master will receive this warning.
    • Unready Tone.
      • A series of fast pips.
        • when operating in Frequency Hopping mode, and the transceiver is synchronizing and not ready to pass traffic.
        • when operating in Selective Communication mode, all unselected transceivers will receive this tone.
    • Low battery Warning.
      • A series of slow pips when the battery is low.
    • Plain Text Tone.
      • A single pip every 2 seconds.
        • when operating in Plain Text mode, during transmission.
    • Crypto Fail.
      • A continuous 1 kHz tone.
        • internal COMSEC failure.
    • Key Alarm.
      • An alternating 2 tone alarm with a 1/2 second pause in between.
        • Operating in Cipher mode with an unprogrammed CSEC key.
        • Operating in Frequency Hopping mode with an unprogrammed TSEC key.
    • Variable Operation.
      • An single pip.
        • occurs when a crypto variable (key) is successfully loaded.
        • Plain Text Cue – In Cipher Text VINSON mode, when receiving a Plain Text message.

Half duplex, frequency-hopping, secure, tactical, digital VHF FM Radio
30 MHz to 108 MHz in 25 kHz channels
Incorporates Electronic Counter Counter Measure (ECCM)
Meets environmental extremes listed in STANAG 2895 and MIL-STD-810D
Conforms to EMC/EMI Requirements of MIL-STD-461C
Integral VINSON compatible crypto module
Conforms to TEMPEST requirements of NACSIM 5100A and CID/09/14

AN/PRC-522: Manpack radio set
AN/VRC-513 (V)1: Medium power vehicle installation radio set
AN/VRC-513 (V)2: High power vehicle installation radio set

Transceiver Characteristics:
Height: 90 mm
Width: 238 mm
Depth: 220 mm
Weight: 4.8 kg

General Characteristics:
Frequency Range: 30 – 107.975 MHz (3120) channels in single channel or frequency hopping
Bandwidth: 25 kHz
Modulation: FM (F3E)
Channels: 8 programmable channels to store single frequencies or ECCM frequency sets
Modes: Analogue or digital; secure or plain text; radio rebroadcast; remote control mode
Frequency spacing/channel steps: 25 kHz
Radio rebroadcast: Mixed modes, Automatic mode selection

ECCM Modes:
Wideband hopping
Narrowband hopping (band selectable)

Barred Bands:
4 frequency hopping
16 frequency hopping
256 frequency hopping

Built-in Tests:
Transmit/Receive level indicator
Battery voltage indicator
Power-on automatic internal module test
Manually initiated internal module test

Power Supply:
Supply voltage: 12V or 28V nominal (to QSTAG 307)
Manpack Rechargeable Battery life: (1:1:8 cycle) 12 hours typical (at 20ºC)
Lithium batteries are also available for Manpack operations

Power output: 0.1 watts, 4 watts, 16 watts and 50 watts depending on configuration (manually or remotely selectable)

RX sensitivity: -116dBm (0.35µV) for 10 dB SINAD (analogue) or 10% BER (digital)
Audio output power: 10 mW into 300 ohms
Volume control: Five stepped volume levels or fixed level audio mode
Spurious response and image rejection: Greater than 85 dB

External Controls:
Channel switch
On/off switch
Crypto switch
Frequency entry
Single channel mode select
Frequency hopping mode select
No transmit/low/medium/high power select
Standby mode select
Radio rebroadcast mode select

Frequency (in single channel), Built-in Test results, selected operational modes

Environmental Characteristics (to MIL-STD-810):
Operating Temperature: -40ºC to +48ºC
Storage Temperature: -51ºC to +63ºC

Low profile manpack antenna
Manpack antenna
Single port vehicular antenna
Rechargeable batteries
Battery chargers
Carrying harnesses
Low profile headset
Fill device
High power RF amplifier (50 W mode)

Other System Components:
Vehicular adapters
Active noise reduction headsets
Adapter tray to interface with the legacy installation harness (for interim usage only)
Log readers

Product Options:
Internal COMSEC: Embedded with Over the Air Rekeying (OTAR) and VINSON compatibility
Tempest certified to NACSIM 5100A and CID/09/14

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