Lost Group Post,



     Authenticating a Spy Radio,




Lost Group Post,

     I've lost the Group Post for Feb.17/98. The feature artical was:

OFF THE SHELF PRICK's; PART IV, PRC-94, if you still have it on file, please send me a copy. Also Alan would like one at <>




      By Alan D. Tasker  WA1NYR

This is the story, as best I can tell it, of the progress that the U.S. Military has made over the past sixty years in mainstream portable voice communications radios.  A "Portable" is defined as a unit capable of being operated while a person is in motion.  Mainstream is defined as having reached some fair production level.  Not included in this discussion are code sending units/beacons or satellite communication units (these are datacom only, i.e. e-mail, maps, etc.).  Also included here is some information on non-mainstream products.
In any work such as this, there is a tendency to pigeonhole items in an attempt to organize and simplify.  This, plus the fact that one is always working with incomplete information, may lead to some inaccuracies.  If you find something with which you do not agree or if you have something to add, please contact me.
If you are unfamiliar with military nomenclature, you might want to visit references 6 and 12 first.

Pictures for many of these radios appear in various web sites, and these are so indicated in the "Sources" section.

General Goals

In general, the goals in the development of new radios were, for many years, as follows (some of which are interdependent with, and some of which are contrary to, some of the others).  
  In more recent years, additional goals have been imposed. 
In addition, there has sometimes been at least a perceived need to develop radios that operate within more than one band (i.e. the AN/PRC-70, 113, 117D, 128, 138, 139, and the AN/URC-100 series).  These radios help "interoperability" with other fighting force elements, as well as communications with local elements when they exist.

The Simple Six

  One can group the types of portable radios the Military buys into the following six categories, four of which are tactical and two of which are non-tactical.  Not every service purchases all types, nor are all types procured in the same quantities.


1. The Squad Radio, VHF FM (wide band), a small hand held unit for very local communications within ground forces.
2. The main ground force communications device, a VHF FM (wide band) backpack, for longer distance communications than the squad radio can provide.
3. An FAC (Forward Air Controller) radio, generally a backpack, UHF, AM, for communications with aircraft.
4. A Special Forces radio, HF, SSB, backpack/manpack, for very long distance communications.


5. SAR (Search and Rescue) radios, originally on 140.58 MHz, then 121.5/243 MHz, then 243 MHz only, and then multi channel, all AM, for downed airmenor other rescue duties.
6. Guard Duty/Fire Rescue/Other Use types, generally Low band (30-50 MHz)or High Band (152-174 MHz), or UHF (450-470 or 512 MHz), and/or the closely associated Government frequencies, narrow band FM.

The Charts 

The following seven charts along with the introductory paragraphs for each summarize these six types of portable radio sets from the beginning (just before World War II) to the present.  Your comments are welcome and are encouraged.


Over the years, certain trends have been evident.  For instance, the Air Force and Army have tended to collaborate and use the same hardware when both services needed the same function.  This can be seen in the charts, especially in SAR and non-tactical radio usage.  Other trends are as  follows.

 The Army has traditionally been the Lead in the Squad radio, although the Marines started the development of the PRC-68.  The Army is also the Lead in the VHF backpack area.  The Air Force has traditionally been the Lead in the UHF FAC area with the Navy and Army tending to use what was developed.  The notable exception is the PRC-75, which was developed for the Marines only.  Additionally, there is little evidence to suggest that the Army has had a need for a UHF FAC radio later in time than the PRC-41 era.

 The Army generally Leads the effort in HF radio development.  The Air force is currently the Lead in SAR system development.  The Air Force is the Lead in the Scope Shield program, which is essentially non-tactical.
The Beginning Steps in Ground Force Portable Radios, Pre WWII-Charts 1 and 7 The style developed in the beginning (battery on the bottom, rigid antenna on the top, front panel controls) was employed for the SCR-194 and SCR-195 for the Army and the TBY for the Navy.  These were not really hand held devices, nor were they built like the backpacks with which we are familiar today.  It is a tossup where to put these early units, so I simply put them in the charts with the most room.

The VHF Squad Radio, WWII to Present-Charts 1 and 7 The first unit, the SCR-511, was designed to be used while riding a horse. However, the cavalry was abolished before WW II, so it would seem it was a bit awkward to use on foot.  Therefore, the honor must go to the SCR-536 for being the first true handheld radio. (Both units were made, in the beginning, by Galvin Mfg. Co, which is now Motorola.)  Packing a walloping 36 mW [B.C. typo in the manual, is really 360 mw] of Tx power, and subject to all the interference the HF AM band musters, it was none the less a success.  The Navy's MAB and DAV were also fairly small units, but not quite handheld.
The Korean War vintage PRC-6 (although there is some debate as to whether it made it through development in time to actually see wartime service), making use of the relatively new sub-miniature (pencil sized) tubes, improved greatly on the SCR-536.  A VHF unit with 250-mW output, the FM mode of this unit reduced the interfering noise level greatly.
After a long and drawn out research effort (basically waiting for transistor and integrated circuit technology to develop), the PRC-68 was produced, a very neat little package indeed.  There had been an interim stop at the PRR-9/PRT-4, the first all solid state implementation, but they never really saw much use. The PRC-68 was to prove to be the father of 6 additional designs, the 68A, 68B(V), 68B(V)2, 126, 128, and 136.
The 1" longer PRC-68A followed, which was one of the first microprocessor-controlled units.  It allowed random frequency programming, but you had to stay within one of the four sub-bands.

The present unit, the PRC-68B(V) (Marines)/PRC-126 (Army) is basically a PRC-68A with a frequency display.  In addition, the PRC-126 has external frequency setability.  They are microprocessor controlled and allow more latitude in channel placement than even the PRC-68A because they have an external antenna tuning control.

The VHF Backpack Radio, WWII to Present-Charts 2 and 7 By all accounts, the first true backpack, the SCR-300, was a very successful design.  It was followed by the Korean War vintage (although they may have just missed actual war service) PRC-8, 9, and 10 (Armor, Artillery, and Infantry respectively). Using sub-miniature tubes, these offered wider frequency coverage than before.

The PRC-25 was the first synthesized unit, offered wider yet frequency coverage, and had just one tube (RF power output stage).  Over 125,000 were produced.  The all solid state but otherwise identical PRC-77 followed.

The current unit is the PRC-119 SINCGARS (SINgle Channel Ground and Air Radio System).  It has an ability to FH (Frequency Hop) in order to avoid jamming.  In addition, the "A" model is called ICOM (Internal COMsec). Comsec stands for COMmunications SECurity, i.e. voice scrambling in order to prevent intelligent interception of message content by the opposition. This model also sports a much longer battery life.
Meanwhile, there is an improvement program underway that has developed and purchased a small number of trial radios.  The following was taken from the WWW (reference 18).

"The Single Channel Ground and Airborne Radio System (SINCGARS) SIP  (SINCGARS Improvement Program) Compatible Portable Radio, the RT-1753(C)/U, is a compact portable version of the SINCGARS SIP radio. This portable radio will be used along with the Lightweight Internet Controller (LINC) and Dismounted Soldier Unit (DSSU) in TF XXI (Task Force XXI) to support dismounted soldier operations and is designed to operate from a dismounted soldier's vest pouch. The radio replaces the current manpack version of the SINCGARS radio. The portable radio includes all SIP performance enhancements to include additional data mode features, embedded COMSEC, an external RS-232 Data Interface and packet switching for access into the tactical Internet. The radio weighs no more than 5 pounds (with battery and antenna), is approximately 1.9 inches by 10.6 inches in size (with battery) and provides selectable output RF transmit power up to two (2) watts and communication range of 3 to 4 kilometers. The portable radio uses a rechargeable NiCad battery pack. Battery life is approximately 6 hours. The portable radio shall consist of a portable radio, an antenna, and battery pack."


Authenticating a Spy Radio,

I need some help from you experts in "spy" radios. A friend wants me to look at a set he has that he believes was a "spy" radio from the 30s or 40s. I haven't seen it yet, but this is his description:

The set is an 8-inch-square cube. It is painted black wrinkle. All controls and connections come out the front panel.  The power cable comes out the lower left corner and is a cloth-covered cable. The case is missing.  The chassis and front panel seem to be spot-welded to each other and then machined. There is no name plate and no maker's-name on any part, including the tubes.

The markings inside are a red stamped "12" next to the receive-transmit switch and next to both tube sockets.  There is also a red "11" stamped next to the terminal points for the power cable.

Front panel controls are : "W. L." using a thumb wheel (wavelength?). "A. T." looks like a varicopler (aerial tune?). "R." and "S." which is a big lever switch (receive and send?).
Large unmarked toggle switch which looks "on-off"-ish. Two pin jacks marked "TEL." Two pin jacks marked "KEY" Two binding posts marked "A and G"

The set uses two tubes (30, 33).

He wants to determine if this is a covert-operation radio or just a standard military or "ham-job." It doesn't sound like any military set I know, nor do I think hams put inspection marks on their homebrew sets.  I need to know some "tips and tricks" to look for to determine if this is an authentic "spy" set or if it's something else.  Does anyone have any clues, like wire type or something? He's supposed to send it to me next month, so I'll try to get the time to take some photos then.

73 DE Dave Stinson AB5S


Dave, it doesn't sound like a "SPY radio to me.

Tubes are too early, and power output would have been too low.

 The first sets used were commercial types, and then only as an expediant(circa early 1942). The British supplied us with our first radios in very short order. These to both use, and get ideas from for the production of our own.

All such sets will be operable from about any AC source 90-250v. And often 6vdc.

They will not always be sterile, often they will have some type of model number, and tubes often will be marked.

They will tune just about anything consceivable by way of antenna.

Only one such radio is known to have been black crinkle, and that was the PRC-5. All others were simi gloss black with one exception, the PRC-1 which was OD.

All will be xtal control on trans and produce a minimum of 10-15 watts TX/CW.

Front panel controls will always be well marked as to their function(mainly due to the very limited instruction the operative might have received).

I'd sooner think this set is an early QRP Ham rig.

The design suggest mid thirties(tubes, and variometer)

Terminology used indicates it's of US origin I/E Europeans would have place and "E" for earth, rather than "G" for ground.

As this is most surely a US set, of  30's design, and the US had no clandestine, or special operational groups until early 1942(we were totally inept at such things at the beginning of the war, and required considerable tutoring from the British).

 I think it's being a SPY radio can be safely ruled out.




Thanks very much for the info.  I have great respect for your knowledge in this area, especially as concerns ground-type equipment, but I do have to interject one thing for us aircraft fellas.

The Navy was spying on German radio comms back in 1937-1941. The RAT system, the true operational ancestor of the so-called "ARC-5s," was designed specifically to listen-in on German manuvers.  That intelligence was shared with the Brits.  It was all very top-secret in its day.  I can say this with pretty good confidence as I worked with a now-deceased gentleman at the Nevada Test Site who was a Navy equipment operator on several of these flights.  He was very closed-mouth about it even at this late date (mid-1980s) and only talked with me about it because I had mentioned the RAT to him.

I can't say how effective the operators and intelligence people were in using the equipment, as all he did was keep it working. The 1939 RAT system, however, was years ahead of anything else at the time.  The 1940 RAV system was an expansion of the RAT's operating specs.

Feel free to post this to the mil list as it's very unlikely this little bit of pre-WW-II cloak-n-dagger is still classified.

73 DE Dave Stinson AB5S

That's a most interesting story, why don't you write is all up for us?

I'm fully aware, I've read all the noted novels, and historic references. However the limit of our secret operations were just listening, and trying to break codes. These activities were left over after WW-I, this was put to a very abrupt stop in about 1929 as " Gentlemen don't Spy on Gentlemen", as our new secretary of state put it when he found out. This resulted in the publishing of "the Black Chamber" by the now disgruntled and out of work ex-official Herbert Yardley former head of the Army's cryptographic service. 30,000 copies of the Japanese translation sold in it's first month in print. The repercussions would hinder US intelligence efforts until the end of WW-II.

Also remember that these were the Depression years, there were no funds available for such activities, we had been reduced to a 150,000 man Army(hardly enough to keep the Heads clean).

See U.S. Army Signals Intelligence in WW-II: A Documentary History, CMH Pub 70-43.
Military Intellligence, a Picture History. Both available from the Library of Congress.
Also War Report of the OSS, by Kermit Roosevelt.                                



 A magazine recently ran a "Dilbert quotes" contest. They were looking  for people to submit quotes from their real life Dilbert-type  managers. Here are some of the submittals.
  * As of tomorrow, employees will only be able to access the building  using individual security cards. Pictures will be taken next Wednesday and employees will receive their cards in two weeks. (This was the winning quote from Charles Hurst at Sun Microsystems).

 * What I need is a list of specific unknown problems we will encounter.

 * How long is this Beta guy going to keep testing our stuff?

 * E-mail is not to be used to pass on information or data. It should  be used only for company business.

 * Turnover is good for the company, as it proves that we are doing a  good job in training people.

 * This project is so important, we can't let things that are more important interfere with it.

 * Doing it right is no excuse for not meeting the schedule. No one will believe you solved this problem in one day! We've been working on  it months. Now, go act busy for a few weeks and I'll let you know when  it's time to tell them.

 * My Boss spent the entire weekend retyping a 25-page proposal that only needed corrections. She claims the disk I gave her was damaged and she couldn't edit it. The disk I gave her was write-protected.

 * Quote from a recent interview: "You are a top flight candidate and I see that you have a lot of education. However, you understand, that intelligence is not really required for this job."

 * Quote from the Boss: "Teamwork is a lot of people doing what 'I'  say."

 * How About Friday: My sister passed away and her funeral was scheduled for Monday, which meant I would miss work on the busiest day of the year. He then asked if we could change her burial to Friday. He said, "That would be better for me."

 * "We know that communication is a problem, but the company is not going to discuss it with the employees."

 * A group of us got together concerning the lack of merit increases this year (even though management got theirs). We made up a bumper sticker and stuck it on the Boss's new Lexus. It reads, "How's my managing? Call 1-800-NO-CLUE!"

 * We recently received a memo from senior management saying: "This is to inform you that a memo will be issued today regarding the subject mentioned above."

 * One day my Boss asked me to submit a status report to him concerning a project I was working on. I asked him if tomorrow would be soon enough. He said, "If I wanted it tomorrow, I would have waited until tomorrow to ask for it!"

 * I worked for a Boss who sent a memo to his assistant to investigate the possibility of canceling the fire insurance and buying a used firetruck for the employees to man.

 * Speaking the Same Language: As director of communications I was asked to prepare a memo reviewing our company's training programs and materials. In the body of the memo one of the sentences mentioned the "pedagogical approach" used by one of the training manuals. The day after I routed the memo to the executive committee, I was called into the HR director's office, and told that the executive vice-president wanted me out of the building by lunch. When I asked why, I was told that she wouldn't stand for "perverts" working in her company. Finally he showed me her copy of the memo, with her demand that I be fired-and the word "pedagogical" circled in red. The HR manager was fairly reasonable, and once he looked the word up in his dictionary, and made a copy of the definition to send back to her, he told me not to worry.  He would take care of it. Two days later a memo to the entire staff came out-directing us that no words which could not be found in the local Sunday newspaper could be used in company memos. A month later I resigned. In accordance with company policy, I created my resignation memo by pasting words together from the Sunday paper.

 * Stick With Me: Our consulting group received a new manager. She recently had received control over another business line as well, which gave her a sense of power and randeur. In the very first meeting with her she told the group "Stick with me!" I am building an empire at this company, and I am going to need little people like you to be Kings and Queens!"

 * I am not making this up. This gem is the closing paragraph of a nationally circulated memo from a large communications company:  "(Company name) is endeavorily determined to promote constant attention on current procedures of transacting business focusing emphasis on innovative ways to better, if not supersede, the expectations of quality!"

 An Army Ranger was on vacation in the depths of Louisiana and he wanted a  pair of genuine alligator shoes in the worst way, but was very reluctant to pay the high prices the local vendors were asking.  After becoming very frustrated with the "no haggle" attitude of one of the shopkeepers, the Ranger shouted, "Maybe I'll just go out and get my own  alligator so I can get a pair of shoes made at a reasonable price!"   The vendor said, "By all means, be my guest. Maybe you will run into a couple of Marines who were in here earlier saying the same thing."

So the Ranger headed into the bayou that same day and a few hours later  came upon two men standing waist deep in the water. He thought, those must  be the two Marines the guy in town was talking about.

Just then, the Ranger saw a tremendously long gator swimming rapidly underwater towards one of the Marines.  Just as the gator was about to attack, the Marine grabbed its neck with both hands and strangled it to death with very little effort. Then both Marines dragged it on shore and flipped it on its back.  Laying nearby were several more of the creatures, all dead as well.
One of the Marines then exclaimed, "Damn, this one doesn't have any shoes either!"


Things We'd Like To See On Company Motivational Posters.....

  1) If you do a good job and work hard, you may get a job with a  better company someday.
  2) It's only unethical if you get caught.
  3) The light at the end of the tunnel has been turned off due to budget cuts  
  4) Doing a job RIGHT the first time gets the job done. Doing the job WRONG fourteen times gives you job security.
  5) Sure, you may not like working here, but we pay your rent.
  6) If you think we're a bad firm, you should see our rivals!  (We suck less!)
  7) Rome did not create a great empire by having meetings, they did it by  killing all those who opposed them.
  8) We put the "k" in "kwality"
  9) If something doesn't feel right, you're not feeling the right thing.
 10) Artificial Intelligence is no match for Natural Stupidity
 11) A person who smiles in the face of adversity... probably has a scapegoat.
 12) If you can stay calm, while all around you is chaos...then you probably haven't completely understood the situation.
 14) We make great money! We have great benefits!  We do no work! We are Civil service members!
 15) 2 days without a Human Rights Violation!
 16) Your job is still better than asking "You want fries with that?"
 17) We are Microsoft. Resistance is futile.
 18) Plagiarism saves time.
 19) If at first you don't succeed - try management.
 21) Never put off until tomorrow what you can avoid altogether.
 22) This can't go on for ever, even the Third Reich only lasted 12 years
 23) Never quit until you have another job.
 24) TEAMWORK ... means never having to take all the blame yourself.

  A Frenchman, an Englishman and Claudia Schiffer are sitting  together in a carriage in a train going through Provence.  Suddenly the train went through a tunnel and as it was an old style train, there were no lights in the carriages and it went completely dark. Then there was a kissing noise and the sound of a really loud slap. When the train came out of the tunnel, Claudia Schiffer and the Englishman were sitting as if nothing had happened and the Frenchman had his  hand against his face as if he had been slapped there. The Frenchman was thinking: 'The English fella must have kissed Claudia  Schiffer and she missed him and slapped me instead. Claudia Schiffer was thinking: 'The French fella must have tried to kiss me and actually kissed the Englishman and got slapped for it.' And the Englishman was thinking: 'This is great. The next time the train goes through a tunnel I'll make another kissing noise and slap that  French bastard again

 1.  What do you get when you toss a hand grenade into a kitchen in France?  Linoleum blownapart.

 2.  A city in Alaska passed a law outlawing all dogs.  It became known  as Dogless Fairbanks.

 3.  Which famous golfer loves to drink wine?  Litre Vino.

 4.  What's the difference between an angry circus owner and a Roman barber?  One is a raving showman, and the other is a shaving Roman.

 5.  In ancient Rome, deli workers were told that they could eat anything they wanted during the lunch hour.  Anything, that is except the smoked salmon.  Thus were created the world's first anti-lox breaks.

 6.  Did you hear about the red ship and the blue ship that collided?  Both crews were marooned.

 7  Did you hear about the two men from the monastery who opened a fast-food seafood restaurant?  One was the fish friar, the other was the chip monk.

 8.  A scientist cloned himself but the experiment created a duplicate who used very foul language.  As the clone cursed and swore, the scientist finally pushed it out the window, and it fell to its death.  Later the scientist was arrested for making an obscene clone fall.


(The preceding was a product of the"Military Collector Group Post", an international email magazine dedicated to the preservation of history and the equipment that made it. Unlimited circulation of this material is authorized so long as the proper credits to the original authors, and publisher or this group are included. For more information conserning this group contact Dennis Starks at,