This file lists some observed info on the GRC-109, RS-1, RS-6, and GRA-71 equipment. Compiled by: Pete McCollum 3810 Whisper Hollow Dr. Colo. Springs, CO 80920 719-548-3525 MCCOLLUM@SSDEVO.ENET.DEC.COM Descriptions ------------ The RS-1 consists of: - Receiver RR-2. Tunes 3-24 mhz in 3 bands: 3-6, 6-12, and 12-24 mhz. Tube complement: 1T4 RF amp, 1L6 converter, 1T4 455 khz IF (two), 1U5 detector/audio, and 1T4 BFO/audio. The 1L6 tube seems to be somewhat hard to find, and is in demand because it was used in certain models of the Zenith Trans-Oceanic radio. It is believed that a 1U6 would work in place of the 1L6, but 1U6's are rare, too. - Transmitter RT-3. Tunes 3-22 mhz, xtal control, accepts crystals with 3/4" pin-spacing (i.e. FT-243), or 1" pin-spacing. Tube complement: 6AC7 oscillator and 2E26 final. - Power supply RP-2 or RP-3. Input is 75-260 VAC, 40-1000 Hz; with switch- selectable input voltage and a meter to indicate the current line voltage. The RP-3 is bigger, and allows operation from 6 VDC using a vibrator circuit. Uses a 0B2 as a regulator for the receiver's B+. The RS-1 was developed for CIA use around 1950 or so. The GRC-109 is the Army adoption of the RS-1, and consists of receiver R-1004, transmitter T-784, and power supply PP-2685 or PP-2684. The only known difference between the GRC-109 and RS-1 is that the T-784 has a connector for a Burst Coder (GRA-71) on the front panel. There is also a GRC-109A set, which is a later model which has a different case with hasp-type lid fasteners, instead of thumbscrews. It also has some cost-saving design changes: for example, the window for the tuning dial is a part of the front-panel casting, instead of being a separate screw-on piece. The RS-6 is more-or-less a miniaturized version of the RS-1. It has a very similar design, but uses submini tubes in the receiver and power supply regulator, and a mini tube as the transmit oscillator. Physically, the complete radio is in four boxes: receiver, transmitter, power supply, and power supply filter unit (which also provides storage for some accessories). The power supply uses a 6X4 tube instead of the selenium rectifiers used in the RP-x; presumably because the selenium units are too bulky. The GRA-71 is a device that allows you to record a message composed of dits and dahs onto a small tape cartridge, then the message is 'played back' at a rate of about 300 WPM, and electrically keys the T-784. The purpose is to 'burst transmit' a message, so that the bad guys don't have enough time to RDF your location. Also, the burst message is not copy-able unless you are able to record it, then play it back at a reduced speed. ? Some general notes and observations: ------------------------------------ The PP-268x/RP-x power supply, in combination with the 'lampholder adaptor', allow the GRC-109/RS-1 to be operated from AC mains practically anywhere in the world. Physically, you can plug into either US-style AC outlets, or into round-pin (European-style) outlets. The round pins can be unscrewed and inverted to change the diameter of the pins, plus the rubber plug is somewhat flexible to allow changing the spacing of the pins. One part of the lampholder adaptor can be used to get power from a standard light bulb socket, or from a bayonet-style bulb socket. Radio Shack sells a Euro-to-US AC plug adaptor that can be used if you don't have the 'lampholder adaptor'. Electrically, the PP-268x/RP-x units accept a wide range of voltages and frequencies. The R-1004/RR-2 and T-784/RT-3 are also designed with flexibility in mind. Note that with the exception of the burst-keyer connector and the power supply connectors, everything uses simple binding posts for electrical connections. I believe that this was to facilitate emergency hookups for antennas, headphones, etc. For example: I can imagine an operative in some low-budget east-European hotel room, with his RS-1 set plugged into the bare bulb socket hanging from the ceiling, the antenna wire draped across the curtain rods, and the ground wire clamped onto the cast-iron radiator (the wire and clamp is included with the GRC-109 set). Discovering that his headphones are missing, he uses the TL-29 knife (also included with the GRC-109 set) to cut the handset off of the telephone, strip the wires, and connect it to his RR-2's 'Phones' binding posts. This would be a messier task if the radio had something like a 1/4" phone jack to deal with. In case the code key on the T-784/RT-3 is damaged, there are binding posts for you to connect a substitute. It seems that Admiral made most/all of the GRC-109 and RS-1 stuff, and that Oklahoma Aerotronics made the GRC-109A's. The "A" models seem to all have an A-suffix on the serial number, and they have snap-type lid fasteners instead of thumbscrews. I haven't found anyone yet that actually used an RS-6 or GRA-71. Please contact me if you have info. RS-6 Notes: - There also was an RS-6A, which used the RT-6A and RR-6A. The only big difference is that the RS-6A tunes 4.5-22 MHz, whereas the RS-6 tunes 3-16.5 MHz. There are also some minor circuit differences, and the RT-6A uses a 6AK6 oscillator instead of a 6AG5. The manual mentions RT-6A serial numbers of up to 9750. - The RS-6 was reportedly discussed in the Feb. 1993 issue of the Antique Wireless Association Old Timers Bulletin. - It is reported that the RS-6 was made by GTE in Waltham, MA. - There are various opinions of the RS-6 being issued to the crews of various aircraft, such as the U-2, B-47, and B-29 - none substantiated at this point. - In my view, the RS-6 is not a very "user-friendly" design - too many cables and wires, with the possibility of hooking things up wrong, and exposed high voltages on male connector pins. The manual also discusses a situation with the keying relay that requires the operator to press the key when changing modes, etc. - how is the operator supposed to keep track of all this? Side-note on RS-6 parts: - The battery clamps are Mueller ClamPipe #58, with flat thumb screws. - The alligator clip on the accessory cord is a Mueller #45. - The wires on the accessory cord are a twisted pair of dark red and dark green, with black string-ties. - The 'hank antenna' is just a 100-foot bundle of AF-gray wire rolled around a rectangular piece of cardboard. ? Dates for certain items have been reported as follows (I cannot verify these dates yet): RR-2 1950-1962 RS-6 c.1953 (The manual Addendum is dated May 1953. At least 2614 units had been made by then.) R-1004 1962-1969 T-784 1962-1969 T-784A 1969-1973 There are three books that I recommend which discuss spy-related gadgetry, including radios. All are by H. Keith Melton. Unlike many books with 'spy' or 'CIA' in the title, these books are accurate and realistic. "OSS Special Weapons & Equipment" - A sort of catalog of OSS hardware, including radios such as the SSTR-1. "CIA Special Weapons & Equipment" - As above, but for CIA stuff. Includes the RS-1, RS-6, RS-8, GRA-71, etc. "The Ultimate Spy Book", published by DK Publishing, NY NY, 1996, ISBN 0-7894-0443-5. A sort of 'coffee-table book', with lots of high-quality color photos. Includes a bunch of non-U.S. stuff. Surprisingly, it does *not* have a picture of the RS-1. Questions --------- - What is "MWO-11-5820-474-35/1"?. Both of the below-listed T-784s have this marking. "MWO" is "Modification Work Order". Perhaps it is a mod to add the burst-coder connector? - What was the 'official' headset with the RS-1 set? The manual shows a fuzzy picture of an 'antique-style' headset with a wire headband and phone tips. - Need any sort of documentation related to the GRA-71. - My GRA-71 produces a specific signal when you press the "IDY" button. I wonder if this signal can be configured differently for each unit? If you have one that puts out a signal, let's compare... As I recall, mine puts out a repeating 'dash' - perhaps the length of the dash can be varied? ? Observed serial numbers and markings: ------------------------------------- model serial contract/other info T-784 GRC-109 transmitter. 32 MWO 11-5820-474-35/1 137 Admiral Corp. Label on panel reads: "MWO 11-5820- 474-35/1, Applied at Depot, Checked 8231 - RJM" 283 FR-36-039-C-4-44845(E) Admiral Corp. Serial is on lid only - panel serial was removed. 709 ID tag screwed onto lid. Serial # on panel is painted, not engraved. 737 FR-36-039-C-5-14591(E) Admiral Corp. Lid's ID plate is self-adhesive foil, but there are holes and captive nuts for original ID plate. Front panel stencil marking: "MWO-11-5820-474-35/1". Front panel sticker: "Overhauled Tobyhana Army Depot 5-8-81". T-784A GRC-109A transmitter. Snap-type lid fasteners. 102A Oklahoma Aerotronics, Inc. DAAB 05-69-C-1302. Cover is stenciled "CO C" above ID plate, and "A30" below. 411A Oklahoma Aerotronics, Inc. DAAB 05-69-C-1302. Has "13" stenciled on cover. Flat-black paint. R-1004 GRC-109 receiver. 121 "Receiver Radio R-1004/GRC-109" stenciled in white on the lid. No ID plate on lid. Panel says only: R-1004/GRC-109, Ser. No. 121. 293 No ID tag on lid. Front panel is painted (silkscreen), and serial # is engraved. 344 ID plate on lid (screwed on). FR-36-039-C-4-44845(E) Admiral Corp. Tuning dial window is clear, not yellow. Knobs do *not* have "RDR" stamped in them. No serial # on panel - panel may have been repainted? "OD 5" stenciled in white on lid. Case is somewhat crudely finished, and has four 'support bosses' built in to the top edge of the casting. 497 Stick-on label on lid. Overhauled by Tobyhana, date code "2117". Front panel ID plate has painted-on serial #. Serial is also engraved in large numbers in the lower-right corner of panel. 743 R-1004A GRC-109A receiver. Snap-type lid fasteners, and a carrying handle built into the side. Oklahoma Aerotronics, Inc. DAAB 05-69-C-1302. 118A Metal ID plate on lid, with screws. This lid is on radio #141A. ID plate has spelling error: "reciever". 141A Has lid #118A. 409A 637A PP-2684 Power supply, operates from various AC voltages and frequencies, or from 6V DC (uses vibrator). 86 No ID on lid, panel ID is painted, panel serial is engraved. 346 FR-36-039-C-4-44845(E) Admiral Corp. ID plate on lid (screwed on). Sticker ID on panel, no serial #. ? PP-2684A GRC-109A power supply (see PP-2684 above). Snap-type lid fasteners. 422A Oklahoma Aerotronics, Inc. DAAB 05-69-C-1302. Square orange acceptance stamp to right of lid's ID plate. PP-2685 Power supply, operates from various AC voltages and frequencies. 55 FR-36-039-C-5-14591(E) 88 Case marked "OD-53 SET-1". 91 FR-36-039-C-5-14591(E) 117 FR-36-039-C-4-44845(E) Admiral Corp. Lid's ID plate is self-adhesive foil. Front panel sticker: "Overhauled Tobyhana Army Depot ?202". Case and panel each stamped "WHO5AO". 329 FR-36-039-C-4-44845(E) Admiral Corp. Front panel sticker: "Overhauled Tobyhana Army Depot 6 5 81". 777 No contractor marking (no ID plate on lid?). PP-2685A GRC-109A power supply (see PP-2685 above). Snap-type lid fasteners. 308A Oklahoma Aerotronics, Inc. DAAB 05-69-C-1302. 517A Oklahoma Aerotronics, Inc. DAAB 05-69-C-1302. CN-690 Provides connection between G-43 (or GN-58) hand crank generator and R-1004 and T-784. Six foot cable, with connector for G-43, on other end is a box containing a VR tube and female connectors that mate with power plugs on R-1004 and T-784. 548A Oklahoma Aerotronics. DAAB 05-69-C-1302. Marked: "Use only when connecting G-43 to R-1004". RT-3 CIA version of T-784. Does not have the codeburst keyer connector on the front panel. (none) Rough/crude casting. Lid marked "DET B-1 MIAMI FLA". Lots of hand-wear on knobs. Key knob is a more rounded shape than others. Serial was carefully removed from panel. The CIA used to have a training facility at a military base in the Miami area, so this unit may have been used there. 6487 Lid marked "RT-3" in small orange lettering. Letter "H" stamped in upper-right corner of lid. "MWO 39" stenciled above ID plate on panel. RR-2 2020 [Unit pictured in manual, and labeled "RR-2", not "RR-2B".] RR-2B CIA version of R-1004. The only known difference is the markings. Tuning dial window is yellow (not sure if this is natural, or aging. Knobs have "RDR" stamped into them. (none) Looks like it never had a serial # marking. 3973 Lid marked "RR-2B" in small orange lettering. Sticker on case "Dec 7 1968". Bottom edge perimeter of case is a sharp corner, not rounded. 6690 Lid marked "RR-2B" in small orange lettering. RP-2 CIA version of PP-2685/GRC-109. 173 [Unit pictured in manual.] RP-3 CIA version of PP-2684/GRC-109. ? Adaptor, Lampholder Consists of two pieces: an adaptor that accepts a male european AC plug and converts to male light-bulb base; and adaptor that accepts male light-bulb base and converts to male 2-prong US-style AC plug. Packaging labelled: 6250-864-3330 DSA-400-70-C-0810 12/69. Mfr.: Bryant. H-65/U Headset, listed as a standard component in GRC-109 manual. 4000 ohms, has matching transformers built into earpieces. Completely covers the user's ears - made for noisy environments. Has PJ-051R plug (old telephone switchboard type, resembles 1/4" stereo plug). An adaptor cable is used to connect to the R-1004. Headband marked "Radalab MX-1081/U". Earpiece marked "MX-239 Radalab". Stenciled lettering says "SFEP 3". HS-301 Earphone used with RS-6. Hearing-aid style. TL-29 Pocket knife, electrician's style, made by Camillus. One sheepsfoot knife blade, and one wire-stripper/ screwdriver blade. Shown as an included accessory in the GRC-109 manual. Camillus still makes this model. BA-48 Dry Battery, 90V and 1.5V. The R-1004 power plug mates directly to battery. CD-1119FR Power cable with 4-prong male plug that mates with PP-2685/2684 receiver connection. Other end has a a round 4-contact female connector. Probably not used with GRC-109 stuff at all, but it fits the PP-268x and BA-48. RR-6 RS-6 receiver. Essentially the same design as the RR-2, but uses subminiature tubes. Tunes 3-15 MHz, in two bands. 3564 3656 4929 5254 5339 RR-6A Tunes 4.5-22 MHz, instead of 3-15. Band edges are at 10 MHz. RT-6 RS-6 transmitter. Very similar design to the RT-3, but the tuning range is 3-16.5 mhz. Has a 6AG5 oscillator and a 2E26 final. 33 [Lowest number covered by the manual Addendum.] 2001 [Serials 2001-2614 had a different antenna impedance 2614 matching switch, in the manual Addendum.] 3532 3877 4608 5349 RT-6A RS-6A transmitter. Tunes 4.5-22 MHz, instead of 3-16.5 MHz. Band edges are at 10 MHz. Uses a 6AK6 oscillator instead of a 6AG5. 9750 [Highest number mentioned in manual]. ? RA-6 RS-6 power supply filter unit. Contains two submini gas regulator tubes and other filter components, and has storage space for accessories. 3532 4216 4499 4527 4721 RP-6 RS-6 power supply unit. Contains a multi-voltage power transformer, 6X4 rectifier, and a vibrator for running from 6VDC. 3532 4902 5271 AN/GRA-71 "CODER - BURST TRANSMISSION GROUP". ID plate is on the side of the box, not on cover. Main unit is "Adaptor, Keyer MX-4498". Complete unit includes each of the items listed below (2 of the MA-9's), plus a second code wheel for the coder, and a cleaning brush that looks like a small optical lens-cleaning brush. Of the two code wheels: one has a plain-text alphabet, while the other has a scrambled alphabet. 194 Arvin Industries Inc., FR-36-039-E-5-15509(E). Plastic case (?). 1420 Arvin Industries Inc., FR-36-039-E-5-15509(E). Aluminum or magnesium case, thinner walls compared to GRC-109, reinforcement ridges (concave) built-in to the case. KY-468 "Keyer", for GRA-71. 128 Arvin Industries. FR-36-039-E-5-15509(E). 788 Arvin Industries. FR-36-039-E-5-15509(E). MX-4496 "Coder, Tape", for GRA-71. 762 Stenographic Machines, Inc. Order no. 36900-PC-63. 1151 Arvin Industries. FR-36-039-E-5-15509(E). MX-4495 "Coder, Tape", for GRA-71. 244 Arvin Industries. FR-36-039-E-5-15509(E). 678 Arvin Industries. FR-36-039-E-5-15509(E). MA-9 "Magazine, Recording Tape", for GRA-71. 1433 Arvin Industries. FR-36-039-E-5-15509(E). 1807 Arvin Industries. FR-36-039-E-5-15509(E). 1818 Stenographic Machines, Inc. Order no. 36900-PC-63. 2391 Arvin Industries. FR-36-039-E-5-15509(E). ? INTERVIEW --------- Following is an interview with Bob Olsen, from a phone conversation in August, 1996. Bob is a retired CIA veteran and Signal Corps radio operator. I met Bob last year at a reunion of folks who used to live on Saipan (in the Mariana Islands, near Guam). In the 50's and 60's, Saipan was a CIA training base. Trainees would be flown in from various Asian countries, trained, then sent back to spy on the Communists and other groups that CIA was interested in keeping track of. I was born there the year after Bob left. Among other things, Bob trained recruits in how to use the RS-1 radio set. -------------------------------------------------- P: What do you recall about 'when & where' the RS-1 equipment was used? B: Well, we used it in the old days, you know, we didn't have satellites in the sky and all that. So when we needed to get information out of a country, we had to find somebody that was willing to go back in and send it out or bring it out, either for nationalistic reasons or for money. I worked with some people from Tibet. These guys couldn't read or write their own language, they had no skills at all, but they were really sharp. I taught them all about 12 WPM of code, and we had to teach them a cryptographic system. Someone else taught them the paramilitary stuff - jumping out of airplanes and all that. So, my job was teaching them communications. In this group [of guys from Tibet], four of them were Buddhist monks, and two traders that used to ride in and out of Nepal on yaks. We've got to train them, then drop them in with the RS-1 gear. We had GN-58 hand-crank generators, and also power supplies to go with the equipment. The hardest thing to teach them was security - how to take care of their cryptographic gear, not get caught, how to not do any operating in a building where they'd be dimming the lights. Basically we taught them to use the GN-58 more [often than the AC power supply]. But security was a hard thing to get across to them, they really just didn't understand that. [Anyway,] these guys all went in and every one of them came up on the air. I was down on Saipan and Taipei waiting for them to come back - they were dropped in from 15,000 feet out of a B-17. But basically, what we used that equipment for was clandestine work - send 'em in with a signal plan and a whole gunnysack full of crystals - they didn't work the same frequency too often. P: Do you recall about what year that would have been? B: They were dropped in in '57 - the last year I worked with [the RS-1] was '58. People would say they can't learn code, but you have to live with them, day and night. And we did - we actually slept with them in their quarters, and we had an interpreter. But, you don't know if they would get in there and then someone would pay them more money, or they would get killed, or something, and you would never hear from them again. So it got kind of nerve- wracking, you work with somebody for 5 or 6 months, you get attached to them. P: What years were you on Saipan? B: [From about] 1953 and '54, and we left in '58. P: You had mentioned to me last year that you had to modify crystals and such? B: Yeah, we had the little [FT-243 crystals], and we'd take them apart and etch them. You could also grind them on a plate of glass with jeweler's rouge, and if you get them too high, you could bring them down a little bit with a little India ink. I did a lot of that - had to get a lot of crystals ready for a run. P: So somebody else would decide what frequencies would be used? B: Well, we had an operations man in the Commo group, and he'd come up with a signal plan: when he [the agent] would come up [on the air], and how often, and what frequency. We didn't want him to sit on one frequency. ? P: Do you remember any maintenance problems with the RS-1, or things that were unreliable? B: No, I don't. You know, the fact that we dropped those things out of airplanes, and everything else, and still had 'em work, it speaks pretty good for 'em. I used the RS-1 on several training missions - they were the old staple. P: Did you use the key that's on top of the transmitter [RT-3], or did you send a separate key with it? B: No, we used the key on top of it. We had no frills on it - we taught 'em to tune it up and use the GN-58 or the power supply. P: Did you ever work with any aircraft radio gear? B: I was a CW operator all through WWII for the Air Force in India. The first good radio that came out was called an ART-13 Collins 10-channel. After WWII, in Korea, we still had them laying in a motor pool. I was a Commo sergeant in a signal company. This stuff was all laying in a motor pool - the [SCR-]399 with a BC-610. I'd go down to the motor pool with a fifth of whiskey and I could get a whole truck load of stuff. I was trained in aircraft [radio equipment] maintenance at Scott Field, Illinois, but I leaned toward the operating side - I was a high-speed operator. A lot of my friends at CIA where old-timers from OSS; although I wasn't with them until the latter part of the Korean war. The ol' CIA was a good outfit. There are bums in everything, but most everybody was trying to do a good job. I think as a whole we did. We pulled off some pretty cagey deals, but that's the only way we could do it in those days. So, I take it with a grain of salt when I hear these reporters bad-mouth the thing, you know? When I was on Saipan, I was basically involved in training, although I did install a big monitoring setup there, with two 10 KW Collins 10-channel transmitters, and three hundred-foot towers. I got hooked into that - I'm basically not an engineer, but the engineer they had his time was up, so sure enough, the Chief of Station says "you're it". I *worked*, trying to dig footings for 100-foot towers through the coral. Old Ely Popovich was an old WWII man that they dropped into Yugoslavia - he was a demolitions expert. I finally ended up with him coming out there with black powder, and blowing footings for all my towers and guys. P: What kind of receiving equipment was on Saipan as part of that station? B: We had SP-600's, and Collins 51-J's. And we had some of those old 542's that come out of the 399 units. I was in Tokyo when the Korean war broke out, and I got the first SP-600 that was built. The old Chief Signal Officer, he was a Major-General, he got 'em for me. Every time MacArthur flew, I maintained solid communications with him. Everywhere he went, I worked him - when he went down to Wake and got fired, worked him when he was going home, and the guy that come over to settle the peace treaty, and they passed each other in mid-air. They couldn't work each other, so I sat there and relayed between the two airplanes for about two hours. CIA picked me up the last year I was in Tokyo, and I worked out of Yokosuka with them. I met an old guy there, Admiral Ueda [or Wada?], he was a communications officer for the Japanese Navy. He was in Washington when MacArthur was a 2nd Lieutenant - that's how old he was. I used to do a lot of procurement for the outfit. We'd go on these trips to different electronic firms, trying to buy stuff. One of them was a clandestine radio [Don't know which model Bob was referring to here - he told me that there were reliability problems with it], and batteries - we were trying to get batteries that weren't ages old. In the Signal Corps, the batteries had been sitting on a shelf for 6 or 7 years, and you'd have to take a wheelbarrow-full of batteries to operate an SCR-300. So, we got to talking [Bob and Admiral Ueda], and he had a son that was the same age as me who was killed in a Japanese submarine. But, he was retired when the war broke out, and they called him back in. He was an interesting old guy - I learned a lot from him - I learned to respect the Japanese. **EOF**