Portable communication


RT-695/ PRC-41

Portable UHF Transceiver based on the ARC51


Photo: On the front of the R/T unit are two plugs for two handsets.  In the RT695A version one of them connects to the KY-38 secure voice  unit.

Either the silver-zinc battery (BB-451/U) , or the ac power supply (PP 3700) is attached to the bottom of the RT695 /PRC-41 transceiver.


The PRC-41 is a portable transceiver for ground-to-air service, built with modified modules from the ARC-51. It is intended for forward air control.

The radio has 1750 channels in the military 225-400 MHz band, spaced 100kHz. Output power is approx. 2W ( 3W max).  The unit is supplied by 26Vdc, at 2A in receive, or 2.8A in transmit plus  a  short (7ms/ 2A ) pulse when changing  the T/R switch from Rx to Tx or back.

The PRC-41 was followed up in 1969 by the PRC-66



                 Transceiver    RT 695 / PRC-41                 28 x 10.5 x 35 cm , 10.5 kg

                 Power Supply      PP-3700                          28 x 10.5 x 19 cm ,   7.5 kg

                 Battery              BB-451/U                          28 x 10.5 x 19 cm ,   7.5 kg

                 Mount            MT 2976     ( vehicle mount, connects to car battery)

                 Antenna           AS 1404     ( omni directional)

                                           AS 1405     ( directional log-periodic)


Circuit diagrams and some data  are here.


Transceiver   Like the ARC51, The RT695 is a triple superhet with fully crystal controlled channels. Differences to the ARC51 are: Manual control, no crystal oven, simplified squelch circuits and only 2W RF output.

Versions: The RT695A has a slightly modified audio circuit  to allow secure voice  communication using the external crypto unit KY-38


Battery    The battery has 16 silver/ zinc oxide cells, filled with potassium hydroxide (KOH).  The nominal voltage and capacity  is 24V, 25Ah, although it was recommended  not to discharge beyond  20Ah.

With a cycle of 1 minute transmit and 9 minutes receive, the battery will last 12 hours at an ambient temperature between –20 and +35 deg. C.

The battery can be recharged up to 20 times with  16 x 2.03 = 32.5V, initially current limited to 2.5A. After 20 recharge cycles, the battery is discarded, and the silver is recycled if possible.


AC Power Supply  The PP-3700  is a transformer-ballast type power supply with 26.5V output at maximal 4.5A, in exactly the same case as the battery.

The PP-3700 is  not physical nor electrical suitable to recharge the battery.




 FM Comm






FM Comm panels


VHF Communication


  TR 1985


UHF Communication






 ARC-52 family





  UHF Comm panels

 ARM47 UHF testset


USB control


Download Pictures


Download Diagrams

Side view of the PRC41. On top the  Rx audio amp, the 1st and 2nd IF module, the 3d IF module, and behind it the Spectrum Generator.


In the middle the tuning gear and the T/R switch.


On the bottom the modulator, the RF amplifier, the  +180V supply and  behind it the Guard receiver.


Below:  The tiny ceramic 7077 triodes in the RF  amplifier glow quite bright .