|
|
|
|
|
|
VHF Surveillance Receiver
- this page is a stub
The R-744A was a general purpose valve-based
VHF surveillance receiver,
developed by the US Army Signal Corps in 1957/58 [A].
The receiver is suitable for AM, FM and CW signals and has a frequency
range of 20 - 100 MHz. It was intended for
intercepting
enemy radio signals as well as for
radio direction finding.
The device is powered by a 24V DC source, such as the battery of a vehicle,
backed up by internal LT and HT batteries.
The complete set, consisting of the radio and various accessories,
is known as OA-1451/PRR
and also known as NSN 5821-00-082-3847.
The R-744A was manufactured under contract of the US Army Signal Corps
by Arvin Industries and by P.R. Mallory Company, Inc.
The radios were used for intercept and direction finding
in Vietnam, Canada and Australia, and were produced
in small quantities, which is why they are so rare and why there is virtually
no information about them on the internet. The receiver was designed as a
Surveillance Receiver and has the advantage of being continuously adjustable.
Furthermore, it was suitable for the reception of
AM, FM and (modulated) CW, whereas most existing receivers were FM-only.
The CIA used a slightly different receiver, the SRR-4,
that was based on the same design.
It covered 50-200 MHz and was also built in small quantities.
➤ More about the SRR-4
|
- R-744A/PRR
Basic model with bandspread knob.
Manufactured by Arvin Industries in the US.
Known serial numbers are 007, 12 and 16 [1].
- R-744A
Later model (without the '/PRR' suffix in the model number.
Differences unknown.
Known serial numbers are 22, 59 and 60 [1].
- R-744(XE-3)/PRR
Later model without bandspread knob.
Manufactured by P. R. Mallory & Co. Inc. in the US.
- SRR-4
Special model for the CIA,
with extended 50 - 200 MHz frequency range.
In addition, it can be powered by 12V DC and from the 110V and 220V AC
mains.
|
- Batteries (A: BA-406/U and B: BA-418/U)
- Directing Finder Antenna
- VHF Antenna
- Headset 600 ohm, e.g. HS-33
- Vehicle Mounting Base MT-1988/PRR
- Power supply unit PP-1481/PRR (internal)
- Power cable (24V DC) CX-4377/U
|
Type Superherodyne Frequency 20 - 100 MHz Modulation CW, MCW, AM, FM Sensitivity AM < 1µV, CW < 0.3 µV, FM < 1µV IF 4.3 MHz Bandwidth 75 kHz ± 10 kHz at 6dB, < 270 kHz at 60dB Calibration Built-in crystal calibrator with 2 MHz interval Rejection IF ≥ 100dB, other 80dB (20-77 MHz), 70dB (77-100 MHz) Power 24V DC (or batteries) Current LT: 450 mA (1.25 V), HT: 13.5 mA (40.5 V) Batteries LT: BA-403/U, HT: BA-418/U Vehicle PSU PP-1481 (XE-3)/PRR Output 5 mW at 1000 Hz into 600 Ω Valves 13 Temperature -40 to +65 °C (Storage -60 to +70°C) Altitude Sealevel to 3 km Humidity ≤ 98% Weight 6.8 kg (8.5 kg with batteries)
|
-
Superceeded by TM 11-5825-203-10 on 9 January 1961.
|
|
|
|
Any links shown in red are currently unavailable.
If you like the information on this website, why not make a donation?
© Crypto Museum. Created: Thursday 14 April 2016. Last changed: Wednesday, 14 October 2020 - 10:17 CET.
|
 |
|
|
|
![Image of the complete R744 setup, taken from the manual [A].](img/r744_set.jpg)