Vehicle Mounted PRC-77 Sets

[phoenix]

I don't think i've seen a cover of any sort for a 77 st. as they are a manpack radio I believe they were considered waterproof enough.

As for the C-42, not my field of knowledge, but i've not seen a cover for one of them either.

[rob love]

I worked with both, and there was never a cover for either. On the same token, you did not leave equipment like that out in the parking lot uncovered. The radio should not get any wetter than the operator. Between ex'es, the radios were normally pulled and stowed in the sigs room or the vehicles locker. Removal of the C-42 as a set (you could leave the top tray on and remove the PSU and the transceiver as a unit) was best left to the younger troopers....I would not try it alone today.

[Treadhead]

During one of my more insane moments, I swapped a PRC-10 for a useless bit of gear, it was only later I found out that apparently the PRC-10 was used in Nam as a base radio linking PRC-77's in the field. (like a relay station, does that make sense? I'm not radio/tech savy)

[JD Baillie]

The AN/PRC 510 set ( the Canadian version perhaps?) was capable of Radio Rebroadcast functions. It took two radios and a linking cable. Similarly the 25/77 set was also capable of this function. While I can't remember about the 510 cable, the 25 set RRB cable had a centered relay. Both setups needed to be about 25 feet appart. Possibly in the early days of Vietnam the older prick 10 was kept in the rear while the newer 25 set went forward. ??

When vehicle mounted the 25/77 set became the 125.

On another historical note Jimmy's became known as 'Zero Beats' due to the tuning tone of the 510.

JD

[phoenix]

A mounted 77 set with full ces is a AN/GRC-160 actually

[JD Baillie]

OK. So why did we call it a 125? Was that the original 25set name?

JD

[rob love]

It's like splitting hairs really. The 25 and the 77 were not identical radios according to this site:

http://www.olive-drab.com/od_electronics_anprc25.php

AN/PRC-25 and AN/PRC-77 in Other Configurations

There were three basic configurations of the PRC-25: starndard manpack, vehicular (called AN/VRC-53 in that configuration), and dual manpack or vehicular (AN/GRC-125 configuration). The PRC-77 also had these combinations available, but with different nomenclature as explained in the following.

AN/VRC-53 components AM-2060 Power Supply and Mounting Tray
AM-2060 Power Supply and Mounting Tray. Click image for view of complete AN/VRC-53 system.

AN/VRC-53 Radio System refers to RT-841/PRC-25 when installed in the AM-2060 Audio Amplifier/Power Supply and connected to the AS-1729/VRC Vehicular Whip Antenna. The MT-1029 Vehicle Mount is used to install the AM-2060 in a vehicle. The MT-1029 also supports use of the VIC-1 Vehicle Inter-Communication system.

AN/VRC-125 dual purpose system (vehicular or manpack) includes the vehicle set up as above, plus the ST-138 web suspenders back pack, battery set and the CW-503 accessories bag.

The AN/PRC-77 is the basic receiver-transmitter equipment used in the vehicular sets AN/VRC-64, AN/VRC-65 and AN/GRC-160.

The AN/VRC-64 is the vehicular version of the RT-841/PRC-77 portable Radio Set, consisting of: Receiver-Transmitter mounted on the Amplifier-Power Supply Group OA-3633/GRC. It also includes the AS-1729/VRC Vehicular Whip Antenna.

The AN/GRC-160 consists of an AN/PRC-77 Radio Set, including all the vehicular components covered above and as noted in the AN/VRC-64 as well as all standard Manpack accessory items. The AN/PRC-77 can be removed from the vehicle and used as a battery-operated Manpack Unit and later returned and mounted back onto the OA-3633/GRC resuming vehicular operation.

So the jist of it is a 25 in the AM 2060 tray (along with the remainder of the installation) is a AN/VRC53, whle a 77 in the 2060 tray with IKEE is a AN/GRC-160. The AN/GRC 125 is a AN/VRC53 setup with the regular manpack components issued alongside.

Thank god I use a 524 set so I don't have to remember all this.