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Index:(14 pages) SSTR-1; From the Horses Mouth Part I, The account of James F. Ranney, The SST-1 Transmitter The SSTR-1; From the Horses Mouth Part II, Reflections Concerning The TR-1, By Dean Cortright The SSTR-1; From the Horses Mouth Part III, Further Reflections Concerning The SSTR-1, By Dean Cortright OLGA; NORWEGIAN RESISTANCE RADIO SET By: LTC William L. Howard *******************************************************

SSTR-1; From the Horses Mouth Part I, The account of James F. Ranney, The SST-1 Transmitter FORWARD; The following material, though it has been in print for many years. It's existence, even to the experts, is generally unknown. Each part in this series was written by a member of the team that developed the SSTR-1(many of them still alive today), & found ways to get them built. These are the men for whom we have so desperately been trying to find an example of their work these past few months. Hopefully this quest will shortly conclude, as an SSTR-1 has been found, & negotiations for it's purchase are under way. I suspect that these accounts where the result of numerous questions that had been asked them over the years. It will become obvious as you read on, that each account was written long after the fact from memory, & that as a result there are some very minor errors or omissions. These will be addressed at the end of each story & some questions presented. I thank Jim Karlow, a member of our group, & son of one of the authors, for making this material available. I hope you all realize the historical significance of this series, save & distribute it in the best manor available to you. It is most distressing that accounts such as these have not been prepared or preserved concerning other equipment of great historical contribution. My admiration for these men, their efforts, & contribution to history, I cannot adequately convey. Most Sincerely, Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN military-radio-guy@juno.com -------------------------------------------------------------------------------------------------

PART I; The account of James F. Ranney, The SST-1 Transmitter In the early days of the OSS it became apperent that a communications branch would be required. On 9 December 1942, General Donovan explained to a special committee ot he Joint Cheifs of Staff(JCS) the basic requirements for OSS communications, and requested permission to form such a branch. His proposal was still being studied on 22 September1942 when he issued an order combining all OSS signal and traffic facilities in the new communications branch. At the same time, a Research and Development division was set up. In November 1942, the R & D division aquired a small laboratory which could privide technical information unavailable from commercial labs and manufacturers because of war pressures. The following two paragraphs are from the OSS War Report Vol.2; "One of the first models of radio apparatus which the Communications Branch undertook to develop was a lightweight portable radio station suitable for clandestine activities. Development work on this problem led to the production of the Strategic Services transmitter/receiver commonly known as the SSTR-1. An early model, designed prior to the establishment of the Communication Branch, failed to perform satisfactorily when delivered for testing. The model operated from 110 or 220 volt AC or DC commercial power, consuming considerably more electric current than was considered necessary, also the antenna tuning circuit was inadequate for agent operation. The early set was adopted for use only as a stopgap pending the development of a better unit." Major Henry Shore was put in charge of the project to design and build an improved version of the "suitcase radio", as a civilian employee of RCA before he entered military service, Shore turned to the RCA laboratories in New York City for help. He was told the labs were already overloaded with government work, and under no circumstances could they accept the job. Major Shore persisted, and ultimately a plan was worked out whereby one of the lab's employees, Earl Anderson, would work on the project at his home, and on his own time. In a letter to Arthur Van Dyke of RCA labs, dated 25 September 1942, Shore requested an AA-1 materials priority, and $200 to cover the cost of constructing the first model. Mr. Anderson was given one of the original portable radio sets for evaluation. He considered the receiver, while not perfect, was adequate, but the transmitter was a hopeless case. It utilized two stages, a crystal oscillator and two tubes in the power amplifier. The tubes were 35-volt heater type, making battery operation impractical. Output was rated at 35 watts. The antenna tuning circuit would not accommodate the wide variations of antenna impedance likely to be encountered in agent operations. He also discovered, with no crystal plugged into the transmitter, it was prone to self oscillation, something that could not be tolerated in a transmitter designed for clandestine operations. Accordingly, Anderson started from scratch with his own design, eventually settling on the single 6L6 crystal oscillator circuit familiar to anyone who was in the OSS communications. The transmitter was stable and efficient, producing 15 watts output with 400 volts on the plate of the 6L6. With a suitable power supply it would be practical to operate it from a storage battery as well as AC mains. The antenna matching problem was solved by using a tapped plate tank coil which made it possible to match a wide range of antenna impedances. The prototype was built on a steel panel 4 inches wide and 9 1/2 inches long. Why these dimensions were chosen is unclear, although Dean Cortright, W9IRY, says that somewhere along the line it was decided the pieces of equipment should be capable of fitting inside a typical European loaf of bread. There were some in OSS Communications Branch who felt the power of 15 watts was too little, so a series of test was arranged. In a letter dated 3 October 1942, Major Shore informed Anderson that he was sending him three crystals for test on 3510, 3910, and 4830kc. The SST-1, which would be set up at Mr. Anderson's home on Long Island: the base station was in the Washington, D.C.area. The base station call was ANNR, and Anderson would use the call ATJS. The "control"(comparison) transmitter would be Anderson's ham transmitter, a Hallicrafters HT-9, capable of 115 watts outputs, 7.56 times that of the SST-1, which at this point was referred to as "Transmitter X". Tests were conducted on 5, 6, and 8 October 1942. The following are excerpts from Mr. Anderson's letter of 10 October 1942 reporting the results: Antenna system: Except in one instance the antenna consisted of a flat top section 50 feet long, suspended 20 to 25 feet high and a down lead inside the building about 15 feet long. The ground was connected to a steam system. Monday October 5 I was very much surprised to have ANNR answer my first call on 3510kc. I did not expect me through WAR also operating on that frequency with higher power....... I then changed to 3910kc. The interference was also troubling on this frequency but not as severe as on 3510 and we were able to work very well. I then switched 4830kc. which ANNR reported to be best because the only interference was from South American broadcast stations, and it was not severe. Tuesday October 6th. This entire evening was devoted to determining the relative signal strength of the two transmitters. A total of 15 test were made in order to average out the effects of fading and interference.....The average report on transmitter X was R 6.05 and on the HT-9 was R 7.6. The antenna current of transmitter X was .4 ampere and of the HT-9 wa 1.1 amperes so that the power ratio was 7.56. Thursday October 8. Solid communication was obtained with ANNR and one further test was. A piece of wire 29 feet long was laid out along the floor and was use as an antenna on transmitter X. The signal was reported as 2-3 but quite readable. The results of the test were considered very satisfactory, and the power or 15 watts acceptable. There was discussion about substituting an RF ammeter for the pilot lamp antenna current indicator. Due to space limitations, and difficulty of obtaining suitable meters, this idea was abandoned. A final decision was made on the frequency coverage which was specified to be 3 to 12 megacycles. A contract was let to the P.R. Mallory Company for a power supply, and the SST-1 was on it's way. -----------------------------------------------------------------------------------------------

( ed) It should be noted that the SST-1 is the transmitter section of the SSTR-1. Also the stopgap radio set mentioned in the beginning of this account is totally unknown to us. Though there were several such radios used, the description supplied in this account does not match any of those known. *********************************************************

MYSTERY RADIO; Candidates Three proposed candidates have been received for the next topics of this heading. In order of their appearing here in future they are, Navy RBZ, BC-721(SCR-585, Navy AMA), & the Marine Corps R-1484/PRR-15. So start collecting your tidbits of info. Dennis The SSTR-1; From the Horses Mouth Part II, Reflections Concerning The TR-1, By Dean Cortright Forward, Over the years, I have heard many of the statements made in these accounts. However, for the most part these were then just rumors, & as there was no documentation at the time to back them up, had to be taken with a grain of salt. As I'm always very hesitant to pass along information that can't be authenticated, I had to keep these stories to myself. I'm delighted to see some of those rumors substantiated in these accounts, and therefore able to share them with all. We have a very rare opportunity to know the real story, without any undo glorification, or added bullshit to enhance sales. Each time I read these stories, I'm saddened that there was only one topic of discussion, and am left wanting for more, much more! All these accounts are *duplicated* to the best of my typing skills, along with any errors they may contain. Absolutely no editing has been done. Any such errors that may be present & obvious will be discussed at the end of the story. Again, it must be remembered that these accounts were being written long after the fact, and mainly from memory. Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN military-radio-guy@juno.com ---------------------------------------------------------------------------------------------------------

Part II, Reflections Concerning The TR-1, By Dean Cortright Shortly after I became a part of the Commo Division. I recall that a shipment of equipment arrived from the U.K. It was one of the radio sets that fitted into a suitcase. It was in several parts, and housed in a "suitcase". There was a receiver, a transmitter and power supply. This unit helped us determine what we would need if we were to come up with something for use on the various electric power sources on the European continent: power levels, types of plugs and the like. To this were added specifications generated by us- other requirements such as the need for operation from 6 VDC (the common vehicle voltage of the day) and possible use from Signal Corps type hand crank generators. The next consideration was a variety of crystal types. both U.S. and foreign, for transmitter control. Then, the equipment must be operated by U.S. operators (different hand keyer), and to be operated without meters if possible, since meters were in short supply, were fragile, and occupied considerable space. You will remember we used bulbs to indicate plate and antenna current in the transmitter. Finally of course, it like it's British counterpart, had to fit in a suitcase. Somewhere along the way. we got the idea each part should fit into a loaf of continental bread. Also our development boys wanted a super-easy antenna tuner that would match everything from a hairpin (they used them during WW-II) to a bed spring, to a long thin wire.So be it- from this came the rotating coil- which could be built in the U.S. The receiver had to be of standard parts such as tuning caps that were available in quantity, etc. The SSTR-1 was what came out of that, with alternate power supply interconnectors to match those of other government supplies, as well as DC vibrator supply, well filtered, etc. Engineers from two manufacturers helped in the development: RDR Inc. New York City, and Pioneer Electric and Research in Forest Park, Illinois, later on. These were the days when finding people to help you often was done on a personal basis, since priorities of all kinds were in vogue. Some of our folks in Washington knew Irving Weiss at RDR, and someone else knew the PERCO people. In each case, the proprietors and engineers were very helpful and responsive. Many of you know the operating details where works out at Area C. Things like color coding crystals for DAY and NIGHT use- and to avoid reference to things like operating frequencies- since many of the operators were not technical at all. We also came up with the calibrating oscillator for netting the receiver on the base station frequency somewhere along the line. The transmitting tank circuit with roving tap did load just about anything you hooked to the terminal. The crystal circuit drew a lot of current element- I don't know if our modern plated crystals will stand it. In those days, we were using pressure mounted crystals which will stand much more current. Also they were easier to frequency adjust. A little rubbing with an eraser got to a frequency a bit higher. And a dab of India ink brought the frequency down a tad. Incidentally, one of the early sample units from Britain was later (after the war) loaned to Thor Heyerdahl, and taken on the Kon-Tiki expedition. He had used one of these sets in his work for his native country's intelligence service during WW-II and wanted the same equipment. RDR and Irving Weiss continued to serve as one of our contractors, and helped develop late equipments. He then got into making transistors, and had some success early germanium units. He was, however, not careful enough with the X-ray equipment used to orient the g-crystals, and ended up with cancer from which he died. I have in my possession (along with other strange development units) a sample of one of his early germanium transistors- a reject, I bet. ---------------------------------------------------------------------------------------------------------

(ed)The TR-1 in the title line of this account should have read SSTR-1 & is a simple type O. The crystal calibrator mensioned was an accessory item included with later models of the SSTR-1, & most likely the SSTR-5. It's designation was SST-102, messuring just 4 x 2 x 2 inches including batteries . Thor Heyerdahl, now isn't that an interesting bit of trivia! Was an OSS, & SOE operative in his country of origin, Norway, beginning early in WW-II. RDR is the abbreviated trademark of Radio Development & Research(or something very close to that), they are credited with building several other items of OSS radio equipment including the SST-101, which was a 100 watt set.. That radio was unknown until last year when schematics of it surfaced & started circulating. We still don't know anything about it, or what it was used for. Dennis ******************************************************

The SSTR-1; From the Horses Mouth Part III, Further Reflections Concerning The SSTR-1, By Dean Cortright Forward, Regretfully, this is the last of this series, & of the material that I have. While it is possible that other accounts were preserved, if so, they are unknown. Did I not say in a prior comment, "I'm left wanting for more, much more!" You can now see why? Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN military-radio-guy@juno.com --------------------------------------------------------------------------------------------------

Part III, Further Reflections Concerning The SSTR-1, By Dean Cortright Hank Shore was on the design of the SST-1. Earl Anderson later worked on the circuit and constructed the first prototype. Design of the SSTR-1 was influenced to a certain extent by examination of the British clandestine radio equipment. I remember that within a month or two of my arrival in Commo Division (and soon after Hank had appeared), we received a copy of the British underground suitcase radio which had been obtained when HQ was set up in the UK, well before George Graveson was there. I assume that Steve Simpson or someone else on the ball thought to ask for it. It didn't have the exact shape factor we used but it was approximately the same; in three pieces: the transmitter, receiver, and power supply. Their power supply had an assortment of plugs for different European AC outlets, and this was helpful. Also, it had some different kinds of crystal holders. That got use into the universal crystal sock which was designed to accommodate whatever type of crystal holder we thought might be encountered. I think they also had a hand-crank generator which we also got into. However we did decide to get some standard voltage spec so we could use what was available. rather than having something built. Power supplies were kicked around a lot. We decided on 115/230 volts and a switch which altered the primary so it could be operated with two windings in parallel for 115, and in series for 230 volts. The transformer cores were designed to handle either 60 or 50hz. Later we found a rather light core that would operate from 400hz as well. The circuit would also accommodate a small gas-driven generator in addition to operation in aircraft. Direct current operation was for six volts which was the standard vehicle voltage in those days. This all took more space , so we made the power supply case a bit wider. Then we had a suitcase made to hold it all, plus crystals and some tools so one could change the plugs, etc. There was also space for a separate key, if available, and the signal plan. The idea for the rotating coil as a loading system came after the first models were built, but I don't remember exactly when that took place. Manufacture was split up at first, with transmitters built one place, the receivers another and the power supply still another. The first rotating coil design was attempted using a GLASS coil form made by Corning. I remember going to their plant to work with them, but they couldn't hold the required tolerances, and after a lot of delay, admitted that. Then we went to cast ceramics and that worked quite well. The final production design was a little beauty. The people that worked with Hank Shore were Maddy Rehm (who was an active ham, and worked for RCA Communications in New York), and Walt Bostwick, who was a customer engineer, traveling from one plant to another do to expediting, etc. Later when Maddy went overseas, Claude Leather did some of the coordinating work in DC. The receiver tuning was a bit touchy. We worked a lot on that and finally got a design which kept the tuning capacitor and coils all on one sub-assembly for greater stability. Also, the range was increased, tuning 2 through 24 mhz or thereabouts. In the Official War Report of the OSS, reference was made to an "earlier model" receiver. I think it was something which was turned out on a Signal Corps contract. I remember seeing one; it was housed in a wooden box about 15 by 15 inches, covered with naugahyde, or something like that. With those high voltage filaments tubes, the inside of the box got plenty hot if it was left on for any length of time, and that contributed to frequency instability. -------------------------------------------------------------------------------------------------

ed) Note the recurrent references in these accounts of "six volts being the standard vehicle voltage of the day", & the unit of measure "Hertz", as apposed to cycles. Both these, especially the later would indicate these accounts were compiled 'after' the late 1960's, as this is when Hertz became the standard unit of measure for frequency. By 1957 12vdc had become the standard vehicle voltage for all domestic automobiles, and later for those of foreign origin. The gas-operated generator Mr. Cortwright refers to is in strange sequence including mention of 400hz power supplies etc. Can we surmise that this generator was of 110vac 400cps ops, rather than the common multi voltage DC types in use elsewhere? This would provide for a smaller lighter unit, with more versatility in it's application. Though this chapter provides some additional information on the "earlier model" set, and 'parts' of that description do match that of known types. The use of high voltage heaters, or parallel RF output tubes still does not jive with those we know about. Nor could the complete radio set utilizing parallel output tubes/30 watts power output described by Mr Ranney in part 1, be contained in the cabinet 15 x 15 described by Mr Cortwright. Then too there is the strong possibility that more than one "earlier model set" was encountered by these authors & those providing material for Kermit Roosevelt (War Report of the OSS). We know that MANY different radio sets went through the hands of the OSS, or it's predecessor the COI, both in the early day's & later as equipment was considered for use. And that several of these early sets were indeed issued as expedients prior to the advent, standardization, & sufficient availability of the SSTR-1 . They came from various avenues including the British, the Signal Corps, & already available civilian types including some that had been in use by U.S. Forestry for years. Some of these were actually used, many more were dismissed outright. As we can see with this volume of prospective, & varied equipment being inspected by numerous persons, that we could have different accounts of different sets, or at least some very understandable confusion. While I have good reason to beleive I know what the "earlier model" set described by Mr Cortwright, & Mr. Roosevelt were(both being different radios). That described by Mr. Ranney in Part 1 remains a mystery. Towards the end of Part III in Mr Cortwright's account, we find reference to "first models", a successive developments where receivers, & transmitters are improved. The text discribes a rotating coil in the transmitter, & an "Oscillator sub-assembly" in the receiver, also haveing an "increased frequency range of 2 through 24 mhz or thereabouts". It is known that variants of SSTR-1 existed at least up to model "E", these emprovements are not incorperated in the serviving examples, nor are they included in the later model replacement, the SSTR-5. These receiver improvements do however exist in the RS-1/GRC-109 who's development we know began before the end of WW-II. I submit then that Mr Cortwright may then have been giving us a chronology of the 'breed of radio & their developments', rather than just that of the SSTR-1. Several other SSTR type sets were also built & is shown by official documents disclosing OSS purchase expenditures, these variants have never been encountered or described, perhaps these improvements were incorporated in those sets. More recent evedence exist to further support this theory, & will be addressed in further issues along with some other questions that have been submitted by our readers. Hopefully the information presented in these accounts will provoke further input that will serve to enhance our understanding. *****************************************************************

OLGA; NORWEGIAN RESISTANCE RADIO SET By: LTC William L. Howard In September 1939, the Germans invaded Poland and WW II began. Within days, Britain and France declared war on Germany. British troops moved onto the continent of Europe and took up positions with the French. Along with all the other preparations for war, Prime Minister Winston Churchill created the Special Operations Executive, The SOE, charged with the mission of ÍSetting Europe AblazeÎ The Secret Intelligence Service or SIS still had the mission to gather intelligence. Agents operating behind the lines would provide the necessary information and co - ordinate activities of resistance movements. The war began as a face off between armies, the French in the Maginot Line, the British on the northern flank facing the Germans in their positions. Referred to as the ÍPhoney WarÎ or ÍSitzkreigÎ, very little happened. In preparation for a May 1940 invasion of the territory of France and the low countries of Belgium, Luxembourg and Holland, the Germans moved to secure Norway and Denmark. On 9 April 1940, the Germans moved into Norway and occupied the country. Thus the Norwegian Resistance was born. In May 1940, the Germans invaded France and in a matter of weeks, over ran the British and French Forces. The British evacuated their forces from Dunkirk and began planning for the eventual return to the continent. Most of the overrun countries established governments in exile in London. At the beginning of 1941 various resistance groups in Norway were brought into an organization named MILORG, Military Organization. This was created to support a possible allied invasion from the west to liberate Norway and to establish law and order in the event of a German collapse, They also conducted sabatouge operations, most notably against the Heavy Water Plant at Rujukan which delayed the development of the NAZI atomic bomb. MILORG was under the command of the Norwegian Military in London and was joined to the SOE. It is reported that MILORG had approximatly 40,000 men under arms. However, before the British could begin supplying arms and equipment, it was necessary to establish radio communication between England and MILOG. The major burden of communication was placed on the British Type 3 Mark II, also referred to as the ÍB 2Î set. (See ELECTRIC RADIO 1995) These sets provided the main comminication link to the base station in England. Usually these B 2 sets were found in each district. Most war movies of the Norwegian resistance show this set in operation. Each district, however had to maintain communication with the out lying areas. Procurement of radios for this purpose was a top priority for MILORG. The man who supplied MILORG with these radios was Salve Staubo, founder of Hovding Radiofabrikk in Oslo. The production of these sets has been covered in the article ÍThe Story of ËOLGAÌ Illegal Norwegian Transmitter-ReceiverÎ in Radio Bygones, Oct/Nov 1991. Less well known and discussed are the ÍHome brewedÎ sets made by the Norwegians from components air dropped from England. These sets were designed so the resistance could monitor BBC and listen for coded messages. They were a very crude but effective means of listening to radio broadcasts. They were also, I suppose, considered more expendable than the OLGA or the B 2 sets. If one of these were captured by the Germans, another could quickly be made. I was fortunate to be loaned one of these sets by LTC Kevin Cunningham, currently stationed in the Penatagon. He had been given the set by the son of his former landlord in Norway. It was a rememberance of him as he was killed in an unfortunate accident. His name was Per Anton Thorvik and while he was not a member of the Norwegian Underground during the war, he had many friends who were and had used this type set. Col Cunningham packed up the set and sent it to me. On first look, it looks like any other home brewed radio of the 1920Ìs. The most distinguishing feature was the excellent cabinet it came in. Although ÍHome MadeÎ the wooden cabinet was an excellent piece of workmanship, a tribute to the Norwegian furniture makers, no doubt, who made it. The radio is made from components that were supplied by the British. While most of the components were taken from 1920s and 1930Ìs stocks, the tube panel was apparently custom made. Interestingly enough, all the components were made so that they could be assembled with out resorting to a soldering iron! It took me a while to figure out what the circuit was but it turned out to be a three stage regenerative receiver. The first stage was an RF amplifier of sorts, the second stage was a regenerative grid leak detector and the last stage was an audio amplifier. The tube line up was a Phillips B 443 as an audio amplifier, a Phillips B 409 as the detector and an unknown tube as the RF amplifier. Unknown as the glass broke on the trip to Florida. My guess was that is was a transmitting tube since the plate was connected to the cap on top, which is normally the grid in a receiving tube.. All tubes were the four pin continental base which made replacement very difficult. The tubes did not have sockets as we think of sockets. A bakelite board had been drilled at the factory and the pin sockets and terminal screws were installed. The connections underneath were then wired to the screw binding posts. All the user then had to do was screw the panel to a wood base and start wiring. Weather this was standard practice in Britain during the 1930s is not known. I have never seen anything like it in the U.S. This led me to the conclusion that it was made for resistance groups. The other components in the set were two variable capacitors, two rotary switches, two fixed capacitors, a resistor in a glass fuze type holder, a jack, which I initially thought was for the headphones and two more sockets for something called a Hoitaler, (which I later found out meant Loudspeaker), two antenna coils which were identified as Rheinartz type coils, and a smaller coil that had a hinge so it could be moved back and forth in relation to the one antenna coil. The final manufactured item was a wire wound rheostat for controlling the filament. The first thought I had was it would have been simpler to use two tubes, why use three? You really didnÌt need an RF amplifier. Then I realized that they were concerned about German radio direction finders picking up the signal generated by the tickler coil and re radiated out the antenna. This was solved by adding an RF amplification stage. Adding an RF amplication stage also solved some other problems. As was pointed out in the 1933 Radio Amateurs Handbook, a regenerative detector followed by one or two stages of amplification and used for CW and telephonie work would bring in amateur signals from all over the world.. At times a radio frequency amplifier ahead of the detector is very desirable. The increase in sensitivity (and perhaps selectivity) can be put to use in receiving signals from great distances. A further advantage of such an amplifier is that it isolates the detector from the antenna, reducing the radiation for the oscillating condition and making it impossible for the antenna, swaying in the wind, to cause the received signal to waver. Considering the weather conditions in the mountains of Norway, this must have been a necessary consideration. The components all had either screw terminals or came with the leads attached at the factory. It probably came in ÍkitÎ form with all the components needed except the cabinet. This would allow the builder to use any form of concealment that was handy and would keep the radio out of sight of the Germans. This particular set was in a cabinet and looked like a radio. I had the basic circuit figured out very quickly but in tracing it, there were several items which were very strange to me. One set of sockets was marked Hoitaler and there was a small jack socket, which I assumed was for the headphones as it seemed to be in the B + circiuit. What I assumed was the socket for a headphone plug, however , turned out to be something else. It was a jack socket but was too small for any plug I had ever seen. I then took the tube mounting board off the base and examined the wires underneath. I quickly discovered this was in the filament circuit! All filaments under the board were wired in parallel except the RF stage which was partly in parallel and partly wired to another power supply. I located a pair of German headphones and they fit in the socket marked Hoitaler. I then figured out that this jack socket was the filament on/off switch. It must have been a metal pin, which when inserted into the socket effectivly shorted the socket and thus completed the circuit. I suppose that a simple pull ring was attached to it which would allow a quick disconnect in case a German Radio Direction finder was spotted and it also served as a key which would keep un authorized users, to include small children, from turning the set on, which would have been possible with a simple on/off switch. I had been so used to looking at WW II Japanese sets and other sets of the period that I was used to seeing red wires for the high voltage circuits. In this case, however, the red wires were for the filament batteries and the green wires were for the plate or anode voltages. Once I realized what these wires were, following the circuit became much easier. The set was designed to make use of two filament batteries. One battery was used to power the RF amplifier and voltage was controlled by a wire wound rheostat. The tube was wired on one side of the filament to the other tubes but was isolated from them by the rheostat and a connection to a separate filament supply. The other two tubes were wired in parallel and the connection to the other filament battery was controlled by the on/off switch. As the RF amplifier tube was broken, I had no way to tell what tube was used and the thought occured that it may have been a transmitting tube which had a different filament voltage. Having asked one expert about this possibility the comment was made, Íamplification is amplificationÎ so the consensus was it could have been a transmitting tube. Since the entire set was assembled from 1920 vintage parts, it is possible that the British designers simply cleared out a ware house and designed a set using what was on hand which included the transmitting tubes of the 1920s. The second stage was the detector stage. This was a regenerative detector. There was, however, no regeneration control. The regeneration was controlled by swinging the tickler coil in an arc to and from the antenna coil. The final stage was an audio amplification which was connected to the detector stage through an interstage transformer. It looked exaclty like the circuit in the 1940 ÍShortwave Beginners Handbook.Î That circuit used a C-battery but in this set one of the filament batteries was used to provide the negative connection for the transformer secondary. In an effort to get the set operational, I had to make a power plug. Using a block of wood, cut to shape and with holes drilled in it so the power plug would fit, I used ball point pen springs to form the contacts and then soldered wires to the springs. And it worked!! The power plug had connections for the two filament supplies, the ground and antenna connections. The next project was to make two power supplies that would look some what authentic. Two small wooden crates were found and 9 volt transistor batteries were wired in series to produce 27 and 90 volts to start. The second crate was filled with Radio Shack single D cell holders and connections were made at each end, one for the filament and one for the detector/amplifier tubes. This would provide 1 1/2 volts for US tubes and could be re-wired to provide 3 1/2 volts for the European 4 volt tubes at a later stage. The next part was to make up a tube socket panel for US four pin tubes such as the Type 30 or VT 97Ìs that were still in use in the 1930Ìs and are easier to find than the British tubes.. I was also considering the possible construction of a reproduction of the set, until I found out the approximate cost a similar cabinet made in a wood shop at todays prices!! The current cost was $180.00 I opted out for a front panel and base!! Once the tube panel was constructed, I proceeded to wire it into the original set using clip leads. I made up an indoor antenna using a 50 foot copper wire and plastic insulators. With an ungodly number of jumper wires I finally managed to get the detector stage working. Sound, sort of in the headphones! I tried to see what sort of a station could be picked up before attempting to get the audio amplifier stage working. There was nothing! I was not that surprised as there are only two local stations powerful enough to be picked up in this area. And they shut down at sunset! I was going to try again in the morning when I received a phone call from a former resident of the area who was an expert on 1920 vintage sets. I had sent him some photographs and a pictorial and schematic that I had drawn. His first comment was that the coils looked like long wave coils, common in Europe but almost useless in the U.S. There was supposed to be one station in this area, the Egmont Key station which is an avaition beacon, on I believe 377KC. It was part of the instrument landing system for Tampa Innternational Airport and another one out in the middle of Tampa Bay coded Picnic which is used as the outer marker on the ILS system for runway 36L. He also said that with a really good out side antenna, I might be able to pick up modern submarine teletype signals. I had a local HAM operator who had a long wave capable receiver monitor the airwaves during a 24 hour period and he said the band was dead. I gave up further efforts to get the set operational. To get the set to a condition where it would work and pick up broadcast signals would require a set of new coils or rewinding the old coils.. This would would then take the set from itÌs original condition as a set built by the Norwegian resistance and convert it to just another 3 stage radio of the 1920Ìs, which can still be found in some quantity. I decided against any further restoration since it was not my set to begin with and that would lower the value of the set. In discussing the set with Craig Smith he commented that ÍOne way comm. (out to the resistance) would likely have been on broadcast freq.(whatever that was). Long wave 200-500KC used huge high powered trans and was prone to static in the summer, but had great range and relative resistance to fading.--MW our broadcast band 550-1600KC was a compromise between power and range requirements and was as high a freq. as could easily be reached w/ trans of the early 20's.--SW anything from 1.6mc-30mc or so , and anything above that was VHF. Í Since there is a great distance between London/Great Britain and the far reaches of Norway, it made sense that this would have been the ideal system for one way communication with the resistance.For two way communication, the short wave sets would have been used. Craig also pointed out that ÍI really don't know for a fact what Freq the Brits used to communicate with the resistance movements. I would guess shortwave because of the greater range for low powered sets.Î The OLGA sets covered 3.5 Mc/s to 16 Mc/s and the British B 2 suitcase covered 3 to 16 Mc/s This set, while not as esoteric as the British B 2 set and the Norwegian OLGA sets, still deserves a place in the history of the Norwegian resistance during WW II. It is hoped that anyone reading this article with more knowledge of the subject will contact the author by phone or by e-mail at: wlhoward@gte.net. THE WILLIAM L. HOWARD ORDNANCE TECHNICAL INTELLIGENCE MUSEUM e-mail wlhoward@gte.net Telephone AC 813 585-7756 ****************************************************