Index:

PRC-25, FORGOTTEN LEGEND; Part I, By Dennis Starks

-Forward,

-In The Beginning,

-The PRC-25(Technical Description),

PRC-25, FORGOTTEN LEGEND; Part II,

-The PRC-25 is Born,

-The PRC-25, "Milestone Radio",

PRC-25, FORGOTTEN LEGEND; Part III

-The Legend Begins(1965-1970),

PRC-25, FORGOTTEN LEGEND; Part IV,

-Forward,

-PRC-25 Legacy,

-Birth of The Ultimate PRC-25(PRC-77),

PRC-25, FORGOTTEN LEGEND; Part V,

-The PRC-25 Legacy Continues, The PRC-77,

-References,

MEMBERS WRITE;

-Misc Ramblings on the PRC 25, From Bill Howard. Bob Simpson, Steve Haney

-PRC-25 Testimony, From Bob Lindgren

-1995 PRC-77 Modules;

-Motorola/PRC-25 Single Frequency Repeater?

-Balloon Borne PRC-25 Repeater, Wayne Eleazer, WB5WSV

-Desert Storm/PRC-77 Jamming?

-Austrian PRC-2200 & PRC-77 Users,

EASY FIX FOR PRC-25/A15 or PRC-77/A35 MODULES; by Conard Murray

ONE STRANGE PRC-25(Italian? French?); From Leandro Traverso & Mario - IK0MOZ

***********************************************

PRC-25, FORGOTTEN LEGEND; Part I, By Dennis Starks

Forward,

- I've title this article "Forgotten Legend" because in the past few years the significance of the PRC-25 has been overshadowed by it's more famous successor, the PRC-77 which in fact is only a slightly updated version of the PRC-25. Fledgling collectors today when searching for their next acquisition often ask/advertize for a PRC-77, when offered a PRC-25 they either stick their nose's up, or admit that they don't know what a PRC-25 is. At best they will acknowledge the PRC-25 but will only accept one as a last resort in the event they are unable to locate a PRC-77.

- It is true that the PRC-77 would become the most prolific tactical military radio of it's type in history, but it was the PRC-25 that was the milestone which got the ball rolling. And while the PRC-77 had been long established in the field, thousands of PRC-25's remained in front line service for at least another 20 years after the PRC-77's introduction. Still today, many thousands of PRC-25's lay dormant in various military storage facilities the world over. In my mind, the histories of the PRC-25 and PRC-77 are synonymous, and should never be separated.

- Our story starts not with the development of the PRC-25, but ten years earlier(yes, only ten years) with the introduction of the SCR-300(BC-1000). The very first VHF FM, front line tactical transceiver ever devised capable of operation while being carried by it's operator. Though it's VHF/FM mode would be received with great scepticism by the world, even in it's country of origin, it would instantly prove it's value under fire. It would set the stage for all such radios to come. Even today's most advanced hand held radios owe their existence to the success of the SCR-300 of 55 years ago.

- Even with the immense success of the SCR-300 which remained a standard issue item for another 10 years in the U.S., and it's allies for at least 15 years, the idea of a more advanced replacement began almost immediately after it's introduction. The rapid advance of technology during WW-II had produced subminiature tubes that could greatly reduce the size and weight of such a field radio. Along with this significant reduction in size and weight could be included greater reliability, simpler operation, greater frequency coverage and stability, reduction of the required FM bandwidth resulting in more channel capacity for a given frequency range, and a great increase in the ease of field servicing.

- By at least 1947 wood "concept" mock-ups of this new generation of radios had been constructed that would almost duplicate the final product. By at least 1950 functioning prototypes had been completed and possibly even an initial order for production radio sets. By 1951 production radios began to filter into the field, and by 1953, the PRC-10 family of radios(including the PRC-8 & PRC-9) had become familiar equipment. They would accomplish all those goals that had been established for the replacement of the SCR-300, and even include some additional "First" in the area of front line tactical communications equipment. These "first" included modular construction which allowed for almost instant repair-ability in the field by personnel with a minimum of training and support equipment. Secondly was the use of the now familiar short "Tape" antenna which has yet to see a viable substitute design after 50 years(prototype PRC-10's used a sectional antenna similar to the BC-1000 which was a British.design). The only thing to remain of the old SCR-300 was it's multi section, collapsible, long "whip" antenna, but now supplied with a rubber coated spring base to prevent damage while in use(another innovation left over from WW-II that is still in use today).

- But even before the PRC-10 had become established in the field, just as with the SCR-300 before it, plans had been initiated for it's replacement. 1949 saw the introduction of the transistor, and with that, a clamor by military planners to find practical applications for it's use. So in 1952, the criteria were set for our newest generation of solid state radios, and development contracts made. Included in these initial development contracts were the requirements for the PRC-25, PRC-35, and the new generation of solid state vehicular systems based on the VRC-12. Of these 1952 beginnings, the VRC-12, and the PRC-25(in the form of a PRC-77 and a multitude of clones) still survive today. The PRC-35, though a viable radio intended to replace the PRC-6, failed to find a niche in military applications that could not be filled by either the PRC-25, or the new squad radios (PRT-4 & PRR-9 which existed on separate developmental contracts). Thus it's great expense could not be justified.

PRC-25/RT-505; First solid state FM, tactical backpack transceiver, also first to use the now standard 150cps tone squelch system.

- Intended to replace PRC-8's, 9's & 10's inclusive. Development started 1958(XC-1) progressing through 1961(XC-3). Experimental versions(XC-1 & XC-2) had continuously tunable auxiliary receivers,this feature was omitted in the final variants adopted in 1961.

- Interring service 1962, very few were fielded till 1964.In 1965 the PRC-25 was officially replaced by the PRC-77 though it remained in first line service till the early 80's & many still remain in strategic reserves today.

- Ops 30-75.95mc, on any 2 preset synthesized channels of 920 spaced 50kc apart.RF power output is rated at 2 watts, actual measured output averages 4 watts. Radio can be used vehicular with the addition of the AM-2060 amplifier/power supply(several other types avail), see VRC-53 & GRC-125 for more info.Requires 3v & 12-15v normally supplied by BA-4386(many battery types exist). Size (RT-505 less battery box) 4 x 11 x 11", 13.5lbs.

- Numerous accessories were/are produced for the PRC-25/77 family to help it fulfil many roles, the major ones are AT-892(short tape antenna), AT-271 & AB-591(long antenna & rubber spring base), AT-912 or AS-1729(vehicular antennas), AT-984(longwire antenna, RC-292(fixed station antenna), AT-784(homing antenna), ST-138(backpack harness), CY-2562(battery box), H-138 or H-189(handsets), CW-503(canvas antenna & accessories bag).

- Over 130,000 set's were manufactured by more than 15 different (domestic) suppliers before production ceased. Ref.#9,#10,#11,#18,#23,#30

PRC-25A; Identical the PRC-25 except for modifications to the A25 module increasing the audio band-width. This to allow operation with TTY & voice security equipment. Ref.#26

PRC-25B; Identical to previous versions of the PRC-25. Suspect that these are overhauled radios & some may have been painted CARC. Also a possibility of the substitution of silicone type solid state devices. Ref.#26

PRC-25, FORGOTTEN LEGEND; Part II By Dennis Starks

- As noted in the first part of this story. Development contracts for the PRC-25 family of equipment were first let with RCA in or about 1952. We are unsure just when the first prototypes might have been produced, but the first hand-built operational versions appeared in approx 1957. These first radios shared only a passing resemblance to those we now know so well. They had the same basic size and shape, but the control panel lay out was completely different, and these controls had not yet been simplified to the point that the radio was operable by the run of the mil average grunt(one feature that would aids it's future great success). The internal design too was completely different from that of the final version. These first prototypes had not yet incorporated an internal power supply to produce the 135v plate voltage needed for the RF output tube(the radio's only tube). Instead, this voltage was derived from the battery just as with earlier tube type radios. A practice that just would not do, and in fact would have left these radio with a problem that had become notorious with it's predecessors.

- Only three experimental versions of the PRC-25 are known to have been built, the PRC-25(XC-1), (XC-2, and (XC-3). Both the XC-1(approx 1957), and XC-2(approx 1958) appear to have been cosmetically identical, and the XC-2 version even used the same case & chassis of the XC-1. But there is a major difference in the apparent direction that the designers would then take.

The XC-1, had an over complicated control panel. This in part was due to the fact that it incorporated what might have seemed a very attractive feature to us, but in practicality, was of little use for a radio of it's intended purpose. This was a built in auxiliary receiver that could be operated completely independent of the radios basic transceiver. This receiver was continuously tunable over the same range as the transceiver, and included a mechanical digital, veeder root type, counter for the front panel frequency display.

- The auxiliary receiver was eliminated in the XC-2 version. It's modules were simply removed, and all associated front panel control markings were just blacked out with paint. Other than the auxiliary receiver feature, these two early versions do not appear to have any other differences.

- It would seem that at mid-development, the designers of the PRC-25 made a radical change in direction towards their goal. Their philosophy on just what the ultimate front line combat radio would be changed dramatically from one of "ultimate versatility", to one of "ultimate simplicity". Was this a simple cost reduction ploy? Possibly, the projected cost of the PRC-25 was VERY high. Or was the plan intentional to make the operation of the PRC-25 as simple as possible regardless of cost? History will show that the choices made, for whatever reason, were the correct ones!

- Besides those things already detailed, the XC-2 still had a couple problems. The high voltage battery had not yet been eliminated, and the control count/complexity was still too high even with the auxiliary receiver removed. The total control count had only been reduced by one, and the positions had only been reduced from 13 of the XC-1, to 10 of the XC-2. By 1960 all these problems would be reduced to a minimum, or eleminated as the PRC-25(XC-3) would be completed for testing. The early high voltage, multi section battery was eliminated by incorperating an internal inverter type power supply to provide the needed plate voltage for the radio's only tube. This from a common low voltage source of 12vdc. The front panel control count had been reduced from 6(& 10 positions) of the XC-2, to 5 controls with 8 positions. Now the radio was simple enough that anybody, regardless of their familiarity with radio, could operate it.

- The radio's only tube(used in the RF output) had not yet been replaced because technology hadn't provided a solid state device capable of yielding the needed power level. This tube(2DF4), though still a draw back, had been specially designed to be extremely efficient, and rugged. It was instant heating so It, and it's associated power supply, only came on when the transmitter was keyed thus reducing excess power consumption to an insignificant level. Though only rated for an output power of 2 watts, 3-4 watts are the norm. In all my years of tinkering with PRC-25's, I have never seen a bad 2DF4! And believe me, I have abused them, possibly more so in civilian life than I did in the military.

- Like it's grandfather the SCR-300, the number of innovations the PRC-25 included are many, and extremely significant. So much so that communications doctrine, and designs, would be changed forever. This earning it the title of "Milestone" radio just as it's grandfather did 23 years before

- It's RF power output was more than twice that of any previous radio of it's type. Greatly increasing communications range, and reliability.

- It was the first "solid-state" radio of it's type, even pre-dateing the relativily simple PRT-4 and PRR-9. Providing for the utmost in field reliability, minimal maintinance, and power consumption.

- It's battery was a simple, small, and inexpensive 12v/3v type which would provide at least the same operational time of it's predecessor at one fourth the size. This not only eliminated the extremely expensive, and dangerously unreliable multi cell/high voltage types but also allowed it's operator to carry along several extra batteries without burden.

- It was the first synthesized radio ever built. This eliminated the complications and difficulty in frequency change that normally required a trained and competent operator. The frequency drift inherent in all it's predecessors had been eliminated, and this new stability allowed for a narrower band width that in turn provided a greater channel capacity for a given frequency range(channel spacing was more than cut in half, from 100kc or 200kc of older radios to 50kc of the new generation). The later was so significant that almost two sections of the previously used VHF spectrum would be abandoned in favor of the more reliable, and less noisy upper portion alone. Thus, this new radio, though at first seemingly expensive, could alone replace more than three systems currently in place, reducing overall communications cost, and field logistical support problems.(Previously, Infantry, Armor, and Artillery all used separate sections of the spectrum between 20-54mc which included their separate associated radios. Now, all these contingents could use the same frequency range of 30-76mc, and the same radio.)

- It was the first radio ever to use the 150cps tone squelch system which would become the world military standard. This completely eliminated operator error in squelch adjustment. No longer would constant re-adjustments in squelch be needed to compensate for a changing ambient noise level. Accidental squelch changes by bumping exposed controls were greatly reduced, or eliminated. Any of these older traits might have resulted in not receiving vital traffic. The least of the advantages this new system offered was a reduction in front panel control count, and a significant step in the direction of operability by any untrained soldier.

- It was the first radio to use as standard, a "low" impedance dynamic(magnetic) type mic element in leu of the old carbon types. The later was extremely temperature and water sensitive, if it got wet, or damp, it was destroyed, not a good idea in a tropical environment. Or if it got extremely cold, the carbon activity would slow, so no good in the snow either! The old carbon types were also notoriously insensitive especially if they had a physically small element(cartridge), it was often required for an operator to yell, point-blank into one for it to pick up his voice, again, not a good idea in combat. Not only did this new mic type have superior survivability, and sensitivity, but's it's low impedance allowed for long lengths of audio cable without fear of hum or interference pick-up. The low impedance dynamic mic would go on to be the type of choice for nearly every kind of microphone application, military & civilian.

- The new generation of radios would abandon all old audio connector types for a much smaller, and simpler one(U-77/old, U-229/new). It's small size would allow for reduced front panel congestion. So much so that two audio connections could be provided instead of just one. These connectors are still the world standard today, surviving in service longer than any other standard type in history.

- It's physical design was unlike any before it. It's extremely rugged construction could(as I have witnessed) survive being run over by the proverbial "tank"! It could be submerged in water at a depth of 6 feet for an hour with no ill effects. In all, the PRC-25 was built to survive, and it's construction/design has yet to be surpassed.

- The host of accessories developed for this radio are astounding. They would allow it to serve in numerous and diverse capacities for which it had never been intended. So great is the number that it is impossible to list even a fraction of them. And while some might think the PRC-25 to be militarily extinct, it's accessories form the foundations for all such radios produced today. They all use audio accessories, antennas(both portable and vehicular), power supply/amplifiers, mounts, batteries, carry equipment, etc that were either originally designed for, or derived directly from, those built first for the PRC-25. If they don't actually use PRC-25 equipment, they all will at least use the same connectors, have the same threads, have the same dimensions, or fit the same foot-print, and will be functionally interchangeable with those of the PRC-25. This after over 38 years, and our transition from Germanium transitors and high power miniature VHF RF tubes(2 watts), to the use of LSI IC's each containing thousands of transistors, and RF transistors capable of 50 watts or more smaller than a postage stamp. I think this is quite a testament!

- The PRC-25 was as ready as the state of the art in technology would allow. So in 1961, the PRC-25(XC-3) was officially adopted as the AN/PRC-25(RT-505). But for whatever reason, it would not be for another three years that it would begin to make it's contribution to history. But when it did, it did so in a BIG way! It would become the most used, and copied radio in military history. Still today, "after 38 years", it remains the standard by which all new designs are compared, and for which complete compatibility must be maintained.

PRC-25, FORGOTTEN LEGEND; Part III, By Dennis Starks

This chapter in the PRC-25's lengthy saga has taken several forms. None seemed to do it the justice it deserves. So I've decided to take a "time-line" approach to it's "Legend". I believe this will make it much simpler for the reader to follow it's progression, and judge it's impact on history.

1952,

Requirements for the new generation of PRC-25 family of equipment are laid down.

1954,

Development contracts with RCA are let.

1957,

The PRC-25(XC-1) appears.

1958,

The PRC-25(XC-2) appears.

1959,

The PRC-25(XC-3) appears early in the year.

1960,

November, Two modified PRC-25(XC-3) prototypes are tested.

In June, the VRC-12 is adopted as a standard issue item of equipment.

1961,

Though the PRC-25 had been officially adopted in May(after two years of testing and refining the final version), for some reason it would not be put into full scale production for another four years.This four year delay in production might be explained later, but by 1965 there would exist a dire need for these radios that surpassed any higher echelon excuses. October of this year saw an initial contract for production units with RCA.

1962,

December, deleveries begin of production PRC-25's.

1963,

In August, initial shipments, and distribution to U.S. forces in Europe begin. Europe had become our traditional test arena for equipment of all types some years before.

1964,

Testing of the PRC-25 family of equipment, including the VRC-12(which had been adopted one year before the PRC-25), had been completed in South Vietnam. A few of the sets were tested by signal advisers who had concluded it was a significant improvement over the older PRC-10's. Despite their favorable conclusions, they were unable to obtain approval for it's adoption as the standard adviser radio. This was due in part to the extreme cost of the radios, and the lack of logistic support in place. Late in the year, 500 PRC-10's are dispatched to South Vietnam as an emergency measure for use by advisers.

1965,

By now only token quantities of the PRC-25 existed which had no doubt been built for the purpose of field trials. When combat troops began to deploy to South Vietnam in the Spring, they were supplied with the same early generation of equipment that the adviser groups before them had been, the PRC-10. Yes, the PRC-10, it was used extensively by all those involved, enemy & allied alike until the late 60's(much later than generally believed by most people).

- In the summer, the limitations of the PRC-10 began to result in excessive combat casualties with the Marines, and the 173d Airborne Brigade, General Westmoreland then issued an "urgent battlefield requirement" for 2000 of the new radios which had been tested in this theater the year before. The Signal Corps responded by shipping the entire stock of PRC-25's on hand(only 1000 sets which had been destined for Europe) and began emergency procurement for the remaining 1000 sets of the order. This initial 1000 new radio sets where in the hands of troops within a few weeks. Of the 2000 set order, 1500 would be received by advisers, and Special Forces, with the remaining 500 going to combat troops.

- An "X" mode requirement(speech security equipment) was added, to specifications for improvements to the PRC-25. This would eventually resulted in a re-designation of the radio to the PRC-77.(Special Note: it was not the redesign to eliminate the output tube that prompted this re-designation, nor the "X" mode requirement alone, it was a combination of all the refinements that would eventually warrant a re-designation to PRC-77)

1966,

"Operation Attleboro", In November, U.S. Forces(a small task force of the 196th Light Infantry Brigade) are prematurely drawn into the heavy jungle of War Zone C to ferret out Viet Cong storage depots. Instead, they stumble on to the head quarters of the notorious 9th Viet Cong Division who immediately surrounded the three company Task Force, cutting off all attempts at relief.

- Throughout the morning of the 4th, relief forces fought their way to the beleaguered task force. Using only a PRC-25, the task force commander, Maj. Guy S. Melroy, eventually controlled eleven companies from five separate battalions while lying pinned down by enemy fire. To aid this miraculous feat, Sfc. Ray Burdette had assemble a ground plane antenna(RC-292) and propped it up against a nearby tree. This for two days before pressure was relieved long enough to effect a withdraw of the battered task force. This was the first time that a large Viet Cong force stood and fought.

- The PRC-25 is now listed as a replacement for the PRC-9, and PRC-10 inclusive, in Australian tables for equipment(which also includes the PRC-64, -41, -47, -62, GRA-71, GRC-106, PRT-4 & PRR-9, and VRC-12 among others).

1967,

15,000 PRC-25's, and 7000 VRC-12's are now in the hands of U.S. troops, and another 9000 PRC-25's are being issued to the South Vietnamese Army. Issue to the South Vietnamese army had been purposely delayed to relieve frequency/traffic congestion.

- November, after the "Battle For Dak To" involving the 173d Airborne Brigade's 2d Division, and the 503 Infantry, against the 174th North Vietnamese Regiment atop Hill 875. Combat casualties for equipment alone were listed as 89ea PRC-25's, 22ea PRT-4's & 19ea PRR-9's(173d Airborne), and 32ea field telephones.(Note these were PRC-25's and not PRC-77's!)

- Combat loses of equipment for this year deplete the Army's entire inventory of tape antennas. As an emergency expedient 15,000 special bushings are fabricated to adapt the old PRC-10's antenna to the PRC-25.

- It is discovered that only half of the radio operators using the PRC-25 are Signalman, or have received any formal training. Most operators are found to be simple infantryman drafted to the radio operator position to replace fallen radioman. The simplicity of the PRC-25 is a great success. Because of this simplicity it is proposed to initiate PRC-25 training to "all" Army trainees, and not just signalman, this is an unprecedented act! Fall of this year saw the completion of testing of the newer PRC-77.

1968,

In May, shipments of PRC-77's began to Southeast Asia. They had been delayed due to deficiencies in the batteries for the KY-38 encryption equipment(because they could not vent, they were prone to explode), and for lack of a single capacitor which had been supplied by a subcontractor gone bankrupt. By December, 9000 sets where in the hands of U.S. troops.

- Theater commanders are unwilling to turn in their PRC-25's upon receipt of new PRC-77's. The PRC-25 had become "Too good, no one wanted to give them up!"

1969,

Those who believed the war was to be fought and won as a counterinsurgency rather than a conventional war, profess that the PRC-25 alone had far more utility than a B-52 and it's associated support, or any troposcatter or satellite terminal.

- In late December, infantryman overrun the camp of the highly successful Viet Cong A3 Technical Reconnaissance Unit. Among the equipment captured included 1400 hand written copies of intercepted Allied messages, 2ea PRC-25's, 1ea PRC-77, and 1ea Chinese R-139 receiver.

1970,

PRC-25's had become the primary targets for specially formed enemy units who entered battle with one mission, to capture these radios. In the beginning, the first priority for the issue of these sets went to Viet Cong units monitoring American traffic. By the early 70's, so many PRC-25's had been captured, or stolen, that it had become a standard issue item for most enemy line units.

1976,

- My first experience of many with a PRC-25(listening to Hispanic TV broadcast off the coast of Guantonimo). As of 1980, I had never seen a PRC-77.

PRC-25, FORGOTTEN LEGEND; Part IV, By Dennis Starks

Forward,

- By the early 1970's, the new PRC-77's had become hopelessly intermixed with the old PRC-25's among all the using armed forces(regardless of country). Those who still had PRC-25's in inventory refused to turn them in being convinced of their value under fire.. Confusion was now to the extent that all official reports, manuals, etc would use their designations interchangeable, as indeed the radios themselves were for all practical purposes. For this reason it now becomes near impossible to separated the exploits of the two different models of the same radio. So we'll continue this story with that of the successor to the PRC-25's 'Legacy', the 'Ultimate PRC-25', the 'PRC-77'.

- History repeats itself! Just as the replacement for the SCR-300 was conceived just as it was introduced, and the PRC-10 had been replaced on paper a year before it had even been established in the field. The first PRC-25's had been in effect replaced before they were born. From the very beginning certain requirements had been in place for it's final version. The first, and primary priority was the elimination of it's output tube resulting in a 100% solid state radio. This early goal was for the PRC-25, and was never intended to result in the PRC-77. But as we will see, the original plans were foiled.

- It would seem that while the PRC-25 had been officially adopted as Standard "A" in 1961, this might have only been an expedient means of relieving pressure on the development-infrastructure. Adoption, did not mean that the sets would then go into immediate large scale production(which it didn't), but it might provide a means of stalling for time while development continued, and prove an effective ploy for obtaining the funds needed for the purchase of limited-production units, and their continued field trials. Indeed, the evidence shows that all those who where familiar with the PRC-25 as of 1965 had been exposed to it as the result of these "Field Trials" being conducted as late as 1964, and.not because of it's issue to any as standard equipment.

- But this Adoption/Extended-Development tactic backfired when in 1965 General Westmoreland issued his "urgent battlefield requirement". As the PRC-25 had been officially adopted as "Standard A", the powers that were could now provide no excuse for not supplying the radios especially as they already had a small quantity in hand. So these trials were brought to an abrupt halt. The unfinished PRC-25 being forced into an early, and hasty mass production by a completely unprepared industry. It would arrive In-Country with virtually no support structure, as one had not yet been established.

- Further development must then, out of necessity, take place under fire from hostile forces in actual combat, as indeed it did. We might conclude then that the development of the PRC-25 was never completed, and the emergency of war forced it's use prematurely. The results of this trial-by-fire would be a radio set that would not see a competent rival for near 30 years.

- Regardless of the PRC-25's premature obligations to war, work towards the replacement of it's output tube continued. Inadequacies began to show up in combat that would in turn be added to the list of it's planned refinements. Most had to do with ancillary equipment such as handsets, batteries, support equipment and logistics. All were quickly remedied.

- But some real problems also surfaced. The first was interference when used in close proximity to other radios, both on receive and creating interference when transmitting. This previously unforeseen problem became apparent when trying to use two like radios back-to-back as a repeater under certain conditions. But it became intolerable when they were combined with dozens of other radios(some being much more powerful) at congested communications sites. All having their antennas mounted inches from each other on common, overcrowded, towers. So included in the PRC-25's refinement package where steps to reduce spurious emissions during transmit, and provide it's receiver with better selectivity.

- In 1965, just as all the problems were solved, and refinements thought to be completed(including the replacement of it's output tube), the Army threw a monkey wrench into the works. It added a requirement for compatibility with speech security equipment(X mode). This would result in a delay of two more years before the deployment of the ultimate PRC-25. These two years where added as the result of bureaucratic mistrust, and foot dragging, rather than any limitations in technology, or industry.

- In 1965, the National Security Agency(that government body having jurisdiction over all encryption equipment, and methods) was asked to develop speech security equipment for tactical units. They were at first reluctant to produce cryptographic equipment for combat infantryman that would undoubtedly be captured. But by January 1966, the NSA would agree to develop the device for portable radios. The NSA and the U.S.Army Electronics Command then designed a new radio from "a modified PRC-25" that could connect to the new speech security equipment. X mode is born. The PRC-77 ?, Not yet !

- The new radio was in fact not "new" at all, it was simply a refined PRC-25! Again, the PRC-77 was not the result of successfully replacing the PRC-25's output tube, this had already been done. Nor was it the result of any other circuit or design changes. It was all these refinements combined, and when joined by the X mode ability, and the deciding factor that 10's of thousands of the earlier radios had already been fielded as the result of the emergency of war. A positive method of distinguishing between the two was now needed. A modified designation such as PRC-25"B" was simply no longer adequate. So now, (less than one year after PRC-25's were first deployed to Vietnam),.the PRC-77 is born! If General Westmoreland's "urgent requirement" had been delayed only a couple of months, there might never have been a need for the designation of PRC-77 affixed to the radio that received it!

- By the fall of 1967 the PRC-77 was still not yet available. Not at all because of any deficiencies in the radio, or protracted development time. All problems had been worked out long before(PRC-25), all testing had been completed, the PRC-77 was in production, the radio was ready! It was again NSA foot dragging, combined with minor problems with the new encryption equipment, that would delay deployment of the PRC-77 till May of 1968. By December, 9000 new radios would finally be in the hands of the troops.

- The new PRC-77 was externally identical to the PRC-25 in every respect. Without it's data tag in place, it is absolutely impossible to tell the difference between the two. Once opened up, only a trained eye can even tell the difference, and most of it's internal modules are interchangeable. But it did boast several improvements; it's receiver had been upgraded with better selectivity, it's transmitter's spurious emissions had been reduced, and of course, the output tube had been eliminated(though some sources will report an increase in RF output/range, any difference is minimal).

- Lastly, the radio's audio bandwidth had been widened to accommodate the new X mode requirement. This would eventually allow the fringe benefit of using various data modes. These modes included MCW*, TTY, and modern day Packet.

*(MCW was used by Australians who did not yet have access to the highly restricted U.S. voice encryption equipment. These devices were protected to the point of paranoia until the mid 70's. Neither had they developed systems of their own. MCW then was their only means of transmitting secure messages. This was accomplished by using an external tone oscillator, and CW key. The same method was also practiced by various para-military groups being supplied equipment by the CIA.)

PRC-25, FORGOTTEN LEGEND; Part V, By Dennis Starks

- By the early 1970's, production of the PRC-25 had ceased. Over 130,000 radios had been built in the U.S. alone. Production had continued even after the advent and large scale deployment of the PRC-77. The PRC-25 had become legend, in the words of General Westmoreland himself, "the PRC-25 was the single most valuable contribution to the war effort". Not the M-16 rifle nor any other item of ordinance, but a lowly radio!

- Though designed for use at a platoon level, the circumstances of war and environmental conditions had made it the primary communications at every level from 10 men to 10,000. The PRC-25 had become the modern day quide-on, or flag, carried at the head of battle charges 100 years before. Just as 100 years before, the quide-on bearer was the primary target of an opposing force, but as he fell, the next soldier would gallantly take up the flag, and charge on. The simplicity of the PRC-25 allowed the same thing, should it's operator fall(as many, MANY, did!), the next soldier would snatch it up and carry on.(many surviving examples of the PRC-25 still retain their unit markings, not just numbers painted on them, but elaborately painted unit crest, or insignia). Even though the PRC-25 was still in the hands of troops, as it would be for many years to come, the Legacy is now carried on by it's slightly younger twin, the PRC-77.

- By 1973, the PRC-77 had been established the world over. It was being produced by at least four domestic manufacturers, and being distributed to at least 10 countries(some in kit form). Foreign companies had begun to build their own for both domestic use, and export. Known companies producing radios include RCA, Magnavox, E Systems, Cincinnati Electronics, Tadiran. Countries receiving radios included U.S., Germany, Spain, Norway, Korea, Iran, Jordan, Lebanon, Israel, Australia, and others. The average cost of the set is $1200.

- In the late 1970's, a viable radio for use at the squad level was finally introduced after 15 years of development, the PRC-68. It would start to make a dent in the needed quantities of PRC-77's as it would no longer be needed at this low level of the command structure.(Neither the PRC-25 nor -77 had ever been intended for use as a squad level radio. Lack of a viable radio, and the limitations of range in a dense jungle environment had forced them into this service).

- By 1980, E-System alone(a Johnny come lately) had delivered 25,000 sets to the U.S. military, and exported over 12,000. By 1985, they had delivered 40,000 to the U.S. military alone, and had exported equipment to 50 countries. In 1981, Sentinel Electronics was added to the list with a U.S. order of over 12,000 radios at a cost of $900 per radio. In 1983, another order was placed with Sentinel for $3 mil, and NAPCO was added as a supplier with $2.09 mil order. In 1984, C & G Associates was awarded a contract worth $1.84 mil for over 2000 radios. By 1986, Iran had begun exporting PRC-77's(six years after their disassociation with the U.S.). In 1989, Lucas Hazelton(AN/COMM) received a contract for $22 mil(the same year that the PRC-119 begins deployment). The above listed data is only the tip of the iceberg.

- By the mid 1980's, the success of the various generations of the PRC-68(including the PRC-126) had proved good enough that they could be used at higher levels than they had been intended, this too would reduce the quantities of PRC-77's needed in the field. Also by this time, there were many usurpers that claimed to be the successor to the vulnerable old PRC-77 both foreign and domestic. They would all prove false.

- Logic might suggest that with all these attacks on the domain of the PRC-77, it would begin a decline from the military seen, but the reverse is true. There were still not enough radios sets in service to meet the demand. Some units of the National Guard and Reserve had to resort to alternate equipment to meet their needs. Radios like the Trans-World PRC-1077 would appear in their inventories. Not because it had been adopted, or was an authorized replacement for the PRC-77, but because it was all they could get, and it had been approved for purchases.

- In 1987 the official successor to the PRC-77 was adopted, the PRC-119. It was grossly over complicated and required the constant attention of well trained operators and technicians. It's extremely complicated/sophisticated design required service personnel to make regular rounds of the units equipped with them to keep radios running. The supposed benefits of Singars, and frequency hopping were lost in the operators inability to set up or maintain these modes, and the radio's frequent failures.

- In 1990, Desert Storm, the U.S. military was sorrily lacking in field communications equipment to outfit it's hurriedly mobilized forces. There were not enough PRC-119's nor it's sister systems to go around. Again, the PRC-77 is put into action, and again there are not enough. Orders are placed with every company known to still produce the radios. Domestic production wasn't enough, and radios had to be imported from Israel, and Germany(VRC-12 systems were similarly acquired). Units that are issued the PRC-77 vice the PRC-119 don't yet realize how lucky they were.

- By 1992 it was estimated that over 500,000 radios had been built in the U.S. alone, and it was still in production for the U.S. Army as of 1994 by NAPCO(six years after the adoption and deployment of it's successor, the PRC-119). By the mid 1990's, units that had been issued their new PRC-119's, and had been forced to turned in their old PRC-77's were begging to get their old PRC-77's back. Experiences during Desert Storm, and after, had proved the new PRC-119 to be too complicated to be operable by the common soldier, and it's temperamental nature required constant servicing. The hard won lessons of Vietnam which had spelled the extreme success of the PRC-25 and -77 had been forgotten! The 40 year old proven philosophy of "ultimate simplicity" as apposed to "ultimate versatility" has yet to be re-learned.

- It's most impressive, that after 42 years, the story of the PRC-25, and the PRC-77 cannot be concluded, nor my account of it. Because they still serve on. Many thousands of PRC-25's still languish in storage awaiting a call to duty, or are used in a diminished capacity every day. And the PRC-77 is still in production(in one form or another), and still in use, all over the world. The age of some radios being nerely twice that of their operators!

- Here is a summary of the longest lived military radios(none would ever approach the production numbers or widespread use of the PRC-25 & -77):

Navy TCS, 1939 to approx 1969, 30 years.

BC-610, 1940 to 1969, 29 years.

Gibson Girl, 1942 to approx 1985, 43 years

VRC-12, 1960 to now, 39 years(and still going)

PRC-25 & PRC-77, 1961 to now, 38 years(and still going)

Dennis Starks; Collector/Historian

Midwest Military Communications Museum

email: military-radio-guy@juno.com

References:

#1, Sig 3, List of Current Issue Items, Oct. 1953.

(Illustrations of the PRC-10 are of the experimental prototypes)

#2, Communication Manual, Dec. 1950, published by the Communications Department, Ft Benning Georgia.(demonstrates the transition from WW-II type equipment to the new generation. Includes many pictures of then experimental equipment including the PRC-6, -10, RT-68, -70 etc)

#3, Military Radio Data Vol. I, PRC Designated Radio Equipment, by Dennis Starks (contains detailed discriptions of all known PRC designated military radio equipment from every country of the world)

#4, TC24-24, 1988, Signal Data References: Communications-Electronics Equipment.

#9. FM24-24,20 May 1977,Radio & Radar Reference Data.

#9A.FM24-24,Dec 1983.

(each of the above contain data and pictures of the PRC-25 & -77 as well as all other current equipment of the time)

#10.Janes, 1979/80,Military Communications.

#11.Janes,1981,Military Communications.

#12.Janes,1988,Military Communications.

A.Janes,1985,Military Communications.

B.Janes,1994/1995,Military Communications.

C.Janes,1996/1997,Military Communications.

(each of the above contain sales/production data, descriptions, pictures and other info for the PRC-25, PRC-77 or both. Also data on non-U.S. clones of these radios)

#14.ECOM 4451,Nov 1976,History of the Squad Radio.

(Contains info on the development of the squad radio including the PRC-35)

#18. Military Communications, A TEST FOR TECHNOLOGY, The US Army in Vietnam by John D.Bergen,CMH Pub 91-12. (contains a detailed account of the development and war time use of the PRC-25 & PRC-77)

#23. Items contained in my personal collection of equipment.

#28. Federal Logistics Data on Compac Disc(Fed Log). 1995

#29. AFP 100-14, May 1980.

#29A, AFM 100-14, Feb.1969

(each contains short descriptions of all current equipment in use by the Air Force at that time. The 1969 edition does not include the PRC-77)

#30. Associated equipments technical manual.

#31, Military Collector Group Post: Backmail #52

CURRENT AUSSIE RADIO EQUIPMENT; Circa 1966, from Dave Prince

#40 FM24-19, 1991, Radio Operator's Handbook.

(contains installation & operational instructions for all current equipment of the time)

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1964 -1967 I was stationed in Pirmases Germany, which was also a Signal Depot PDO yard. I made many visits to the PDO yard and began to see many PRC 10s and PRC 6s showing up as scrap. Also a radio I had never seen before. It was the RT542(VRC 48 ). Based on this, I assumed that new radios were coming into the system.

Keep in mind that, I was with a nuclear weapons related unit and we uesed the USAREUR telephone lines for communication ( Iron Virgin) and out on the SASCOM sites they had an ITT system connected to a central at Heilelberg. As a result I never saw a tactical radio.

1967 I went to Vietnam and was with the Technical Intelligence unit. We were not authorized radios. In mid 1968, we got in a recaptured US radio which we all thought was a new US radio as none of us had ever seen it before. We were dissapointed when one of the older NCs told us it was the GRC 9 of 1950 vintage. First time I saw a PRC 25 was when we were trying to restore one of the re captured sets to operational status for use by our team in I CTZ.

Captain Paul Marro, the team leader wanted it so he could stay in touch with the USMC units in case he ran into trouble on his many excursions to the field. I saw it but did not get to use it.

It was not until 1973 and then with the USAR/NG that I had the opportunity to make use of one of these sets.

William L. Howard

THE WILLIAM L. HOWARD ORDNANCE TECHNICAL INTELLIGENCE MUSEUM <wlhoward@gte.net>

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DENNIS: I AM ENJOING THE PRC-25 ARTICLES. OBVIOULY A LOT OF RESEARCH IN THERE. TWO COMMENTS:

1. I HAVE TESTED A BUNCH OF -25'S AND -77'S, AND THE DIFFERANCE IN THE POWER OUTPUT IS REAL. VERY FEW -25'S HAVE EVER BEEN OVER 2 OR 2.5 WATTS AT THE BEST PLACE IN THE BAND. MOST -77'S ARE BETWEEN 2 AND 3 WATTS, ONE I HAVE SEEN HAS BEEN OVER 5. HAVING SAID THAT, THE DIFFERANCE BETWEEN 2 WATTS AND 4 WATTS INTO THE SHORT ANTENNA (FOLDING DUMMY LOAD?) IN TERM OF ACTUAL RANGE IS LIKELY TO BE A FEW HUNDRED YARDS.

2. A COUPLE YEARS AGO I BOUGHT A PILE OF PRC-77'S. THESE WERE TURN IN'S, MANY OF THEM FROM THE SAME UNIT ACCORDING TO MARKINGS ON THE RADIOS. MY GUESS IS THAT THIS UNIT HAD UPGRADED TO SINCGARS AND DID A WHOLESALE TURN IN OF ALL PRC-77'S. IN THE MIDST OF THIS BATCH, THERE WAS A PRC-25. THIS RADIO MUST HAVE BEEN IN SERVICE AS LATE AS 1995. THIS WAS NOT A SERVICE UNIT, OR SHOP OR DEPOT, BUT A COMBAT ARMS UNIT. SO LETS SEE, 1965 TO 1995 = 30 YEARS. NOT BAD.

WILL YOU ADDRESS THE RT-505B/PRC-25? AND SINCE THERE IS A -B, WHAT WAS THE RT-505A?

THANKS

STEVE HANEY

HANEY ELECTRONIC CO

<tc0654@mesh.net>

Ed) the only known data on the PRC-25A & B models was included in Part I of the series.

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Dennis,

Recently picked up some PRC-77 modules and thought you might be interested in the following information. They were procured for the USMC and most are dated 9/95.

Supplier was:

FIDELITY TECHNOLOGIES CORP

2501 KUTZTOWN RD

READING, PA 19605

Another bit of information showing the long service life of this radio.

73

Joseph W Pinner +

KC5IJD / NNN0PHR

EMail: kc5ijd@sprintmail.com

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Dennis,

I read in one source that during the Gulf War, the US Forces PRC-77s were jammed by the Iraqis in the Khafji area. Do you have anything more on the electronics warfare against communications networks during the Gulf War?

Jan Bury

e-mail: yahya@orient.uw.edu.pl

Ed) I've never heard of any official account of PRC-77 being jammed during Desert Storm. But I'm sure it took place if only in a very limited capacity.

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Hi Dennis, I was just going through the PRC-25 legacy article and noticed that the PRC-25's mentioned are all PRC-25 A or B models. Mine is a straight PRC-25 RT-505 made by RCA s/n 2838, order number H-6-00053(E). Is anyone keeping track of the various manufactures and contract numbers for the PRC-25. What if any are the differences between the original PRC-25 and the A and B models?

Thanks,

John WD5ENU

John Watkins <jwatkin9@idt.net>

Ed) The focus of that series of articles was on the unlettered PRC-25, and the information on the A & B models was speculative as varied, and differing, accounts have been received as to what their differences were.

I once tried to keep an accounting of the contractors and subcontractors that built the PRC-25, but found the effort futile as there were so many. Then when the PRC-77 entered the picture, it became impossible to track the numbers built, and by whom. A limited(tip of the ice burg) sampling of contractors/numbers where presented just in an attempt to give the reader some idea as to how prolific these radios were/are.

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I'm looking for background on 2 types of military radio: a frequency-hopping portable reported to have been briefly used by paratroopers in WWII and a single-frequency repeater built by Motorola and derived from either a PRC-25 or -77 for use in Vietnam.

A. Frequency-hopping WWII set - I had been told some years ago by a knowledgeable individual that portable frequency-hopping sets were used by Allied paratroopers in WWII but were not successful due to the time base's inability to keep the units in sync.

B. I have also collected some fragmentary information on a single-frequency repeater that Motorola built up in limited numbers from standard FM tactical packset transceivers during Vietnam. Located at a high central point, it allowed all field units to communicate on the same channel, rather than on different channels as in the typical retrans configuration between 2 radios. The modification consisted of an audio delay line between the audio output and microphone input and an automatic PTT circuit that keyed the transmitter at around 3000 Hz.

Whatever was received during the receive part of the cycle was stored in the delay line until the next transmit cycle, when it was automatically retransmitted.

I'd be very interested in obtaining first-hand information on this unit, including a schematic of the conversion kit or its Motorola part number.

Jack Sullivan

<jsulliva@eclipse.net>

Ed) Question 'A', It is fact that the actress Heady Lamar did file for a patent in the early 40's, on a system that embodied todays frequency hopping techniques(as well as Cell phones). It is not known whether any such system was tried during WW-II.

Question 'B', It is true that Motorola built an experimental single frequency repeater system based on a heavily modified PRC-25, and it did work(I once owned one). The set was a basic PRC-25 control panel/chassis mounted in a cabinet which extended the width of the radio about 4" on either side. The system used time domain switching, that swapped between transmit & receive at a rate the couldn't be detected by the humon ear(in fact you could hear a slight motor-boating). I remember reading a construction article in a ham radio magazine some years ago that used the same system, and even allowed connection to telephone lines. I'm not familiar with any system that used an audio delay line.

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Hi, Dennis!

The PRC-25 is the only tactical radio that I've had experience with. The USS Quapaw had four PRC-25's assigned, but we had a tough time getting fresh batteries. Since we were an Active Reserve ship, our supply priority was low. Sometimes months would go by before the supply depot coughed up what we wanted, it was faster and simpler to go to a boat store and buy what we needed out of our own pockets. This applied to small stuff like resistors, caps, stainless-steel hardware for antenna mounts.

Once, I even found an IC chip we needed at a local swapmeet. Anyway, we couldn't get fresh batteries through Supply in time for our training voyage to Hawaii, so we raided the local military surplus store for out-of-date but usable batteries. This was 1985, and I had never seen lithium batteries before.

We thought they were all dead, but they came to full life after a ten minute warm-up in receive. We used the radios between the ship and the fire-barge during fire-fighting training, and, when the Captain took the motorwhaleboat out for a "test" (fishing trip), we were able to communicate over twenty miles of water using the long antenna. I have no doubt that PRC-25's will still be in use by Reserve and National Guard units well into the next century.

I notice that very few military radios get mentioned in history books, but this will be one of them.

Bob Simpson

<n0ntc@train.missouri.org>

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Dennis,

I just read your story about the PRC-25 and 77's on the Military Radio List. It was very good and informative and describes accurately how dummies had to use them and could not be too complicated. I'm living proof.

In August, 1969 I was on operation Durham Peak, high in the Que Son Mountains, about 25 miles southwest of Da Nang and right in the middle of the operation our platoon RTO was choppered-out making our squad radioman the new platoon radioman. It only took five minutes or so for my squad leader to find a guy to take my job of humping two sachels of C-4 and I then inherited the PRC-25.

It was on-the-job training 'cause I had never used a radio/transmitter in my life but, it was a snap! I never even heard of a PRC-77 until a few years ago. I now have a few of them as well as a half dozen, or so, PRC-25's, including an Italian one contracted under RCA license. I guess I'm trying to save them all from the Government band saw blade.

Makes me sick when I hear how they dispose of good stuff!

Thanks for the article!

Bob Lindgren

Proud Marine R.T.O.

<PLT1032@aol.com>

Dennis.

On Tue, 7 Mar 2000 10:31:58 -0500 "Perry Shull" <pshull@cvn.net> writes:

Thank you very much for this site. It brought back tears and great memories for me. My name is Perry Shull from Gettysburg Pa and I was with H&S co. Com/radio 1st bn 1st Marines 1st Regt. in Viet Nam from 6/67-7/68. Recently, a lot of the guys from my unit are getting together on the net and we are trying to remember some of our past. I accidently found your site. It really made me feel good.

The radio's that we started out with over there were the Prc-6, Prc-8,8a, Prc-9,9a Prc-10,10a. Then came our best one, the Prc-25 and then the Prc-77. We had the Prc-47, Prc-41,and the Trc-75. We had some older radios and jeep radios, but I just can't remember what they were. We were also talking about some field telephones. We remember some of the names,EE-8, Ta-1, Ta-312,and a switchboard SB-22. Some of the radio jeeps were Mrc-83 and Mrc-87. Both had a Trc-75, but one had an uhf ( tac air ) radio. The Mrc-109 had one radio and the Mrc-110 had two. I think they were called RT-512, not sure. They were on the same freq-range as the Prc-25 and the Prc-77.

I'm looking for pictures and history on this com/gear and maybe by finding some of these things will help to trigger some other things.

Again thanks for having this site. I have been looking every where for sites. This is the first one.

Perry Shull

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Enjoyed reading your article on the PRC-25. An impressive work. And the "Prick-25" is not forgotten by anyone who served in Vietnam or anyone who knows them! I have a PRC-25, a PRC-6, the remains of a PRC-10, a couple of RT-70's, and a Navy WW II MAB set. I thought I would tell you something a friend told me when I mentioned to him that I had picked up a PRC-25 for free.

My friend worked for NSA or someone like that during Vietnam. They came up with the idea of hooking two PRC-25s together to produce a repeater. Then they would lift the whole arrangement aloft with a balloon to see what kind of coverage they could get. On its initial deployment in Vietnam, within minutes of the balloon-borne PRC-25 repeater being floated aloft, they made contact with a frantic squad that had been out of radio contact, lost for days, and was running out of food and ammo. That little experiment saved those guys rear ends...

Thanks for the article.

Wayne Eleazer, WB5WSV

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Check this link, the Austrians use PRC-2200, PRC-77's and others.

Bundesheer - Tragbares Kurzwellensystem PRC 2200

Jan Bury

e-mail: yahya@orient.uw.edu.pl

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by Conard Murray

Hey Dennis,

Here is a cheap and easy fix for the PRC-25 A15 or PRC-77 A35 1 MHz spectrum generator module. The A35 in my 'new' PRC-77 was dead with either a dead xtal or T1 or both. I had tried rewinding T1, but after three tries of fussing with that tiny wire I gave up. I am too cheap to shell out the bucks for a new module if I could make something else work. Poking around the junk box, I found I had a 1 MHz oscillator module (something like $3.50 from Jameco) handy. I measured the current drain of the oscillator module and determined a 2400 Ohm resistor would drop the 10 Volt line available in the A35 to the 5 Volts required by the oscillator. A 78L05 would work great here in place of the dropping resistor, but I didn't have one on hand. I removed the xtal, placed the oscillator module upside down in the old xtal space and soldered pins 1 and 7 (n/c and ground) to the module frame. I hooked pin 14 to the 10 volt line through the 2400 Ohm resistor. I removed C3, the 10 pF coupling cap between the old xtal oscillator (Q1) and the pulse generator stage(Q2). I hooked pin 8 of the oscillator module to the base of Q2 through a .001 cap. I also removed T1, since it is not needed now. My A35 module now works perfectly. This fix should work fine for an A15 too.

Now I will probably get notes telling me that A35 modules are five for a dollar with free shipping from Fair..... BTW, Dave at Fair has been helpful to me in the past. Now to see how long the A31 will take to get here from Fair. I paid $20 for it ..... I dunno if that is too high or not, but I'm desperate.

Thanks for all you do with the MGCP!

Conard Murray

<WS4S@infoave.net>

QRV 51.6 MHz no tone in scanner ... tone on the PRC-25

***********************************************

ONE STRANGE PRC-25(Italian?, French?); From Leandro Traverso

I have found a model of this radio manufactured in Italy from company STIRER S.p.A. of Pomezia, the radio at first examination is equal to the classic American model, except for a squelch level control locationed on the front panel close to the BNC external antenna connector, and the two bands of frequency from 26 Mhz to 48,95 Mhz and 49 Mhz to 71,95 Mhz. The serigrafia of the panel is in the Italian language.

Inner the difference are more obvious:

the module power supply completely different and without the high tension for the final valve. The final module instead of the valve mounts a transistor with opportune fin for cooling. The modules are all marked STIRER S.p.A. even if writen in the English language.

The radio is marked as model AN/PRC-25-IT the matriculation(serial number) is 002, the number therefore low makes me thing that the radio is a copy of pre series or for evaluation tests(prototype), as this model never has been adopted from the Italian Army, in fact the radio adopted was the ER-95/1 similar to the PRC-25 but of entirely Italian design.

Whoever is interested in photographs of this radio can inquire to my E_mail address.

73, Leandro (IW1PTX)

<kraven@alinet.it>

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Hi Dennis here some notes about Leandro questions. Around 1965 Italian army started a program to replace PRC-8/10 and GRC3/8 series of sets. Many italian companies submitted samples for evaluations often starting from existing sets to cut development time or offer an already tested set. PRC-25IT has been probably the STIRER proposal while the winner of the contract was the ELMER with a set line of French origin (Thomson ER-95 or military nomenclature TR-PP-13).

The Official italian nomenclatures for this set family are: RV-3/13/P : that is the manpack type and it is the basic unit (ER-95A) common to other configurations. Is is suitable for squad and company communications.

Main perfomance :

Solid state construction. Voice in FM mode, Range 22 to 71.95 MHz in 2 bands with 50 Khz tuning steps. Power 1.5 W. supply 22-30 Vdc.

RV-3/13/V : Vehicular version. In addition to basic unit there are : PSU type BA-301, Mounting SP-203A, ATU type BX-33A, Interphone amplifier AI-100.

RV-4/213/V : AFV or Tank purpose. Formed by RV-3/13/V plus Auxiliary receiver R-95C, RF power amplifier AM-215A, PSU for RF amplifier BA-302. The ouput power for this set is 20 W.

After this I think that the Leandro set it is a very rare object (usually were built 3 sets for sampling), may I have a pictures ?

and the ER-95 it is not of Italian design but French infact ER means Emetteur-Recepteur, BA means Boite d'Alimentations....

Mario - IK0MOZ

<mario.g@pcg.it>

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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 concerning this group, the use of our material, or membership contact Dennis Starks at:

A list of selected articles of interest to members can be seen at:

For an itemized Index of MCGP topics see:

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