Delco 5300 vs PRC64
Delco 5300 A and AN/PRC-64:
Delco 5300 A (Serial No: 24)

is a Spy Radio, like its predecessor GRC-109 : It was developed by DELCO for the CIA and has a very compact size.

It works from 3.0 to 8.0 MHZ.

The solid state radio has a watertight housing , the operational elements, however, are not watertight.
It is switched on by opening the lid. A Morse key is built in; it operates a microswitch below the front panel.

Transmitter and receiver have separated crystals of the CR-78/U- type, four channels can be switched separately for the transmitter as well as for the receiver. The antenna is tuned with the help of a small bulb, a whisper- function can be switched on.

It can be operated in CW and AM modes, AM being not common for a spy radio. Though solid state, small and battery operated, it is no portable radio, because it uses wire antennas.

Frequency range:
 
Channel 1:  3.0 ... 3.9 MHz
Channel 2:  3.8 ... 4.9 MHz
Channel 3:  4.8 ... 6.3 MHz
Channel 4:  6.2 ... 8.0 MHz

AN/PRC-64



























Delco 5300A mentiones 5 antenna lenghts, AN/PRC-64 mentiones 7.
Connectors for ANT and GND are different.
Batterytest-knob and -bulb changed their places


Technical data:

Channels:
4 for transmitter as well as receiver, crystal controlled
Mode:
CW, AM
HF output:
CW: 5W; AM: 1.5 W
Sensitivity:
CW: 2 µV
AM: 5 µV
CW- speed:
up to 300 wpm with burst code keyer GRA-71
Battery:
BA-1509/Prc64: 4V, 12V, 24V
Date of issue:
1965


PRC-64: the Army adoption of the Delco 5300. Tunes 2.2-6 MC, has BW switch on receiver, battery-test circuitry is simplified (tests only the 24V), transmitter uses a larger type CR-89 crystal (so that receiver and transmitter crystals cannot be accidentally interchanged???). The CW key on the PRC-64 is implemented with a panel-mounted microswitch, thus perhaps making it easier to keep the front panel watertight.

PRC-64A: same as PRC-64, except that there is an added 'daughter board' on the transmitter module that improves high-speed keying performance. The PRC-64A manual says that all PRC-64's were modified by the addition of the daughter board, thus making them PRC-64A's. However,  an unmodified PRC-64 that was formerly a "parts unit" at the Tobyhana repair depot. The ID plate on PRC-64A's indicates a contract date of 1968.

Developed from the DELCO 5300 A for the US Army. Except the frequency range, the technical data are the same as the data of the DELCO 5300 A.

It works from 2.2 ... 6.0 MHz

It was developed in the USA, but was used in great numbers by Australia and its allies during the Vietnam War period.

All PRC-64 are said to be modified to the improved model PRC-64A (for use of a burst code keyer GRA-71), but unmodified radios still can be found.

Frequency range:
 
Channel 1:  2.2 ... 2.85 MHz
Channel 2:  2.8 ... 3.65 MHz
Channel 3:  3.6 ... 4.7 MHz
Channel 4:  4.6 ... 6.0 MHz
PRC64 Review by KI6SN   |                Army Tech Report No. 67-01       |         Unclassified Defense Dept. PRC64 Doc    |
WA3WSJ operating PRC-64 Manocacy Hill, PA