Click for homepage
RX
USA
CIA
BND
RS-49
  
RT-49 →
  
RR-49
CIA spy radio receiver · 1964

RR-49 is a transistorised miniature clandestine shortwave receiver, developed around 1964 by the US Central Intelligence Agency (CIA), and manufactured by Collins Radio Company and Delco Electronics. It was commonly used as part of the RS-49 spy radio set, but also as a stand-alone receiver by the CIA, the German Bundesnachrichtendienst (BND) and the Belgian Staatsveiligheid.

The device is housed in a molded metal case in grey hamerite colour, that measures 100 x 71 x 40 mm and weights just 370 grams without the 9V block battery. The device is suitable for AM and CW reception of Short Wave (SW) frequencies between 3 and 24 MHz, divided over 3 bands.

The frequency can be freely adjusted with coarse and fine tuning knobs in combination with the frequency scale at the upper edge. Alternatively, the frequency can be determined with a crystal – shown in the image on the right – which can be useful when using predetermined channels.
  
RR-49 receiver with crystal installed

The RR-49 was initially developed for the RS-49 spy radio set, but was released separately before the complete set was ready. As a result, it also became a popular stand-alone receiver for agents operating in a (hostile) foreign country, not least because of its low power consumption. It could be used for 18 to 20 hours from a single standard 9V block battery. The device is known to have been used by the American Central Intelligence Agency (CIA), as well as the German BND [3]. The device is functionally similar to the German BN-48 (UHU) receiver, that was released in 1958.

The receiver by itself was also used by the Belgian State Security Service (Staatsveiligheid) [1]. It is also known that the RR-49 was often presented to former CIA communications officers on their retirement, until at least 1995. This suggests that there might have been a surplus stock [1].

RR-49 receiver
RR-49 - left side
RR-49 receiver with crystal installed
Frequency scales
RR-49 receiver compared to the size of a hand
RR-49 with earphones connected
Secret CIA polaroid photograph of RS-49 agent radio [4]
Secret CIA polaroid photograph of RS-49 agent radio [4]
A
×
A
1 / 8
RR-49 receiver
A
2 / 8
RR-49 - left side
A
3 / 8
RR-49 receiver with crystal installed
A
4 / 8
Frequency scales
A
5 / 8
RR-49 receiver compared to the size of a hand
A
6 / 8
RR-49 with earphones connected
A
7 / 8
Secret CIA polaroid photograph of RS-49 agent radio [4]
A
8 / 8
Secret CIA polaroid photograph of RS-49 agent radio [4]

Features
The image below provides an overview of the controls and connections of the receiver. Apart from the external power socket and the antenna terminal, all connections and controls are located at the top surface. At the front left are two sockets: one for the connection of a pair of earphones, and one for a crystal with a HC-6/U base. If the crystal is not used, the receiver can be used with the internal Variable Frequency Oscillator (VFO) by setting the XTAL selector to OFF.

Overview of the controls and connections of the RR-49

In VFO-mode, the frequency can be adjusted with two knobs – coarse and fine – in combination with an accurate film scale. The scale can be calibrated by pressing the CAL button, turning the frequency controls until a tone is heared, and then shifting the white hairline at the centre of the frequency scale until it lines up with the nearest 1 MHz mark on the frequency scale.

A wire antenna should be connected to the spring-loaded terminal at the left side. The terminal can be released with a knob at the top surface. Surprisingly, there is no ground terminal. When the device is used in combination with the RT-49 transmitter, the antenna would be routed through it. The device is powered by an external 12V DC source – connected to the 3-pin socket at the right – or by a 9V battery that can be installed in the battery compartment at the bottom.

Versions
  • RR-49
    This is the initial version, introduced around 1964 and made by Collins Radio in Cedar Rapids (Iowa, USA). The device featured here is of this type.

  • RR-49-001
    This is a slightly later version, also made by Collins Radio and introduced in December 1965. The circuit contains several improvements over the original design of 1964.

  • RR-49A
    This is a later version, made by Delco Electronics. It is externally identical to the above versions.
Russian twin
The RR-49 is very similar to the A-610 (SEZHA) that was used by the intelligence services of the former USSR – the KGB – for the same purpose. The two receivers are shown side-by-side in the image below. Not only are the dimensions similar, the functions and features are nearly identical. It seems therefore likely that the Soviet A-610 (SEZHA) was modelled after the American RR-49.

Click to see more

Apart from the similarities, there are also differences. The front panel of te A-610 is made of die-cast aluminium, whilst the RR-49 is housed in a molded enclosure. The crystal socket of the A-610 is suitable for different types of crystals, whilst the RR-49 is only suitable for HC-6U crystals.

 More about the A-610 (SEZHA)


Controls
Frequency scales
Bottom side
With open battery compartment
Socket for external power supply
RR-49 receiver compared to the size of a hand
Headphones connected to the RR-49
RR-49 with earphones connected
B
×
B
1 / 8
Controls
B
2 / 8
Frequency scales
B
3 / 8
Bottom side
B
4 / 8
With open battery compartment
B
5 / 8
Socket for external power supply
B
6 / 8
RR-49 receiver compared to the size of a hand
B
7 / 8
Headphones connected to the RR-49
B
8 / 8
RR-49 with earphones connected

Block diagram
Below is the block diagram of the RR-49 receiver. At the left is an RF pre-amplifier, followed by a mixer where the signal from either the VFO or the crystal oscillator (XTAL) is added, resulting in an IF signal that is further amplified and passsed through a 455 kHz ceramic ladder filter. The resulting signal is then fed to an AM detector and amplified in an AF stage to headphones level.


For the reception of CW signals (morse), an adjustable Beat Frequency Oscillator (BFO) can be enabled by moving its knob from the leftmost position. The signal from the BFO is injected directly into the IF Amplifier. It produces an audible tone when the morse signal is active.



Interior of the RR-49 seen from the top left

Interior
The enclosure consists of a metal base plate – with a hinged lid covering the battery compartment – and a molded case shell. The latter is held in place by 7 screws: 2 at the left, 2 at the right and 3 at the top. The interior can be accessed by removing these screws in addition to the two black knobs of the GAIN (volume) and BFO controls (release the small screw at the centre of the knob).

The case shell can now be removed, as shown in the image on the right. All mechanical and electronic parts are mounted to the base panel.

Due to the highly compact construction, the device is not very service-friendly and would have to be taken apart completely in case it had to be repaired or adjusted. Nevertheless it had an extremely long lifespan. The receiver featured here is still fully operational after more than 50 years, which is generally not the case with most modern domestic equipment. Apparently, only first class components were used for the RR-49.
  
RR-49 receiver removed from its aluminium enclosure

The image above shows the interior of thereceiver as seen from the top right. At the front is a sub-frame with a tape- or film-type frequency scale. Note that the calibrate-switch is mounted to the top of this frame. Also note that the 3-gang tuning capacitor is shielded with a brass panel.

Interior
RR-49 receiver removed from its aluminium enclosure
RR-49 receiver interior, seen from the top right
RR-49 receiver interior, seen from the top left
RR-49 receiver interior, seen from the bottom left
Interior (RF section)
Tuning section
Close-up of AF/BFO section
C
×
C
1 / 8
Interior
C
2 / 8
RR-49 receiver removed from its aluminium enclosure
C
3 / 8
RR-49 receiver interior, seen from the top right
C
4 / 8
RR-49 receiver interior, seen from the top left
C
5 / 8
RR-49 receiver interior, seen from the bottom left
C
6 / 8
Interior (RF section)
C
7 / 8
Tuning section
C
8 / 8
Close-up of AF/BFO section

Specifications
  • Year
    1964
  • User
    CIA, BND
  • Purpose
    Agent communication
  • Type
    Superheterodyne
  • Circuits
    RF amplifier, Mixer, LO, IF, Detector, BFO, AF
  • Frequency
    3 - 24 MHz
  • Bands
    3 (see below}
  • Calibrator
    1 MHz intervals (±0.5%)
  • Modulation
    AM, CW, MCW
  • Sensitivity
    10dB S/N 1
  • Selectivity
    3dB (5kHz), 6dB (12kHz), 40dB (16kHz)
  • IF
    455 kHz
  • BFO
    ±4 kHz
  • Rejection
    Image: -20dB (3-18 MHz), -10dB (>18 MHz)
    IF: -55dB
  • Response
    300 - 2500 Hz (±3dB)
  • Battery
    9V block battery (18-20 hours)
  • Power
    12V DC (external) ±10%
  • Consumption
    75 mW
  • Accessories
    Earphone
  • Temperature
    -30 to +45°C
  • Storage
    -40 to +60°C
  • Dimensions
    100 x 71 x 40 mm
  • Weight
    370 grams (without battery)
  1. AM: 0.1mW, 15µV input, CW: 0.1mW, 5µV input.

Bands
  • White
    3 - 6 MHz
  • Red
    6 - 12 MHz
  • Green
    12 - 24 MHz
Documentation
  1. RR-49 Receiver, Operating Instructions
    CIA, date unknown. Approved for release by CIA on 23 April 2014.

  2. RR-49 circuit diagram 1
    CIA, date unknown, but probably 1964.

  3. RR-49-001 circuit diagram 1
    CIA, first drawn 1964, last updated 2 December 1965.

  4. Instruction Book, Receiver RR-49 1
    Collins Radio, 1964, 1965, 1966. 2nd Edition, February 1966.
  1. Kindly provided by Pete McCollum [1].

Publications
  1. Trip Report - Development f the RT-49 and RP/A-49
    CIA Memorandum, 28 February 1963

  2. Chief, OC-OS to Chairman, Equipment Board, Equipment Procurement
    CIA Memorandum, 2 January 1964

  3. Equipment Board staff meeting, Agenda
    CIA, 9 January 1964

  4. CIA Equipment Board staff meeting, minutes
    9 January 1964

  5. Trip Report - RT-49/RP-49
    24 November 1964

  6. Trip Report - RT-49/RP-49
    22 December 1964

  7. Trip Report - RR-49
    22 December 1964

  8. Inspection Report No. 1 - AN/B-62
    CIA Memorandum, 11 May 1966

  9. Inspection Report No. 5 - RT-49/RP-49
    17 June 1966

  10. Inspection Report No. 6 - RT-49
    CIA Memorandum, 21 June 1966

  11. Inspection Report No. 2 - AN/B-62
    CIA Memorandum, 24 June 1966

  12. Equipment Board Meeting, Agenda
    CIA, 8 November 1967

  13. Long-Range HF Communications Equipment
    7 April 1969
References
  1. Pete McCollum, The RS-49 HF Radio Set
    Retrieved November 2020.

  2. Louis Meulstee, RR-49
    Wireless for the Warrior, Volume 4, Supplement chapter 112. August 2019.

  3. Detlev Vreisleben, Personal correspondence
    November 2020.

  4. Unknown source (probably CIA). Secret images of RS-49 set in suitcase
    Crypto Museum archive CM303622. Date unknown, but probably ~ 1965.
Further information
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 05 November 2020. Last changed: Wednesday, 31 March 2021 - 20:17 CET.
Click for homepage