(c) 2000,2008 Peter McCollum
Early Military Equipment
Described in this section is "clandestine" equipment
that was developed primarily by and for the U.S. military before 1945. Some of
this equipment was used by the OSS at various times, but the primary user was
probably Military Intelligence (or paratroops in the case of the PPN-2 Beacon).
|
PRC-1/RT-30 Radio Specifications |
|
|
Weight |
32 lbs |
|
Dimensions |
18” X 13.25” X 17.25” |
|
Tube complement |
Xmtr: 807, 6V6. Rcvr: 6SG7, 6SA7, 6SK7, 6SL7, 6J5. P.S.: 5R4. |
|
Input power |
115, 150, 200, 220, or 250 VAC, 50/60 Cy. |
|
Frequency Bands |
2-5 MC, 5-12 MC |
|
Power Output |
30 watts |
|
Miscellaneous |
J-37 key, hi-Z phones output (can be
reconfigured for lo-Z ?). Xmtr xtal control only; rcvr tunes AM or CW. |
A
PRC-1 radio set. Image courtesy of Chuck Brydges, W4WXZ. Now in the collection
of Richard Dillman, W6AWO.
The PRC-5 "Suitcase
Radio"
|
PRC-5 Radio Specifications |
|
|
Weight |
25
lbs |
|
Dimensions |
11” X 10” X 4” |
|
Tube complement |
|
|
Input power |
110/220 VAC, 50/60 Cy |
|
Frequency Bands |
4-16 MC in 4 bands |
|
Power Output |
10-16 watts |
A PRC-5 radio set, with a manual dated 21 June 1944. Image courtesy of Michael Crestohl W1RC.
Schematic diagram of PRC-5 (291 KB)
This
is an AR-11 transceiver, made by ARF Products. Note the strong similarity with
the PRC-5 – it is clear that they made the PRC-5 as well. ARF was in River
Forest, Illinois beginning in 1942. Image courtesy of George Briggs.
SCR-504 Radio Direction
Finding Receiver
The SCR-504 was used for counterintelligence
purposes, to aid in locating an enemy transmitter. It was mounted in a suitcase
so that it could be fairly discretely carried on the street. Because of the
internal loop antenna, rotating the set would change the signal strength, thus
giving the operator an indication of the direction of the signal.
An
SCR-504 RDF receiver. Note the loop antenna, and the eight tubes along the bottom.
Image courtesy of William L. Howard.
Top
view of the SCR-504, showing the whip antenna protruding through the case, and
the operator’s controls under the handle, allowing basic functions to be
adjusted without opening the case. Image courtesy of William L. Howard.
RT-37/PPN-2 Beacon
Transmitter-Receiver
The PPN-2 is a transponder beacon, used
primarily for marking a ground location for aircraft to use as a homing signal.
The PPN-2 Beacon, and the aircraft-mounted APN-2 interrogator, were known to
the British as the “Rebecca-Eureka” system. See “Wireless For The Warrior,
Volume 4” for details on the system.
Image
courtesy of William L. Howard.
Image
courtesy of William L. Howard.