MILITARY COLLECTOR GROUP POST, Jan.7/98 INDEX: MYSTERY RADIO; the PRR-15, Part II, by Dennis Starks, WHATSIT; HARP? MEMBER PROFILE; Pete Williams HUMOR; *********************************** MYSTERY RADIO; the PRR-15, Part II, by Dennis Starks FORWARD, Did the PRR-15's Dictaphone support a variety of tape speeds? If so, could it have been used to record GRA-71 msgs, then play them back at copy-able speed? Just a thought, Pete ------------------------------------------------------------------------------ Pete, The recorder included with the PRR-15 was not really a dictaphone. It simply allowed for the operator's narration of the recorded signals. The same is included on current equipment of the same ilk. Our search for the equipment used in the GRA-71 application, I don't think will be found in any particular set. Rather it will most likely be simply the recording apparatus. The radio equipment listed as in use by the Special Forces "B", & "C" detachments (which would have needed to receive, then slow down to copy the GRA-71's signals), was of the most ordinary type, GRC-26's (including the R-388), GRC-19's, & later the GRC-106's. Besides the PNH-5 tape recorder listed as part of the PRR-15, the manual list provisions for use with an external TNH-4 or PNH-4, perhaps when we find out what these are we will know more. GENERAL, The PRR-15, and it's major component, the R-1484, were obviously designed for intelligence gathering purposes, much like the R-901/GR, R-395/PRD-1, R-744/PRR, TRQ-30(R-1218, R-1518) etc. If compared to some of those other receivers listed above, the PRR-15 had several very obvious advantages as listed below. #1) it was a 100% solid state design. #2) operation was from a multitude of various power sources, including 12vdc, & 110vac. #3) as a set, it was much smaller than any of it's contemporaries. #4) it had a much wider frequency range than any of the other radios in this family. Even if compared to the current TRQ-30 which requires two receivers to cover a similar frequency range. #5) and expanded modes of reception include AM/FM/CW/ & SSB. While the example in Bill's collection includes more of the accessories than that in mine, I do have the advantage of a manual copy. TM-05599A-15, Dated May, 1969. Saddly though, the manual does not list the sets intended purpose. As of 1969, other radios of this type were still in their experimental stages, these include the R-1410(XE-2)/GR circa 1967 which lead to the R-1518, R-1218(XE-3)/UR circa 1968. The standard issue set for other branches of the service then, and later, was the PRD-1. If you have ever seen one of these 1950 vintage monsters the need for it's replacement becomes immediately evident. So it would seem that the Marine Corps with it's PRR-15 beat the rest of the U.S. military services in the race to devise a viable replacement for the extremely antiquated PRD-1(which by the way remained a standard issue item with the Army & Air force until 1980). THE RECEIVER, Built by Zenith Radio Corporation, Chicago, Illinois, the R-1484/PRR-15 boast some very impressive features not found on any other receiver of it's time, and very few today. Most notable is it's continuous frequency coverage of .54-205mc in ten bands, even the current TRQ-30 with it's two receivers would only cover .53-150mc. The receiver has IF frequencies of 455kc(.54-9mc), .455 & 2.9mc(8-30mc), and 10.7mc(30-205mc). Narrow and Wide bandwidths can be selected that switch between 6/10kc(.54-30mc), 40/120kc(30-205mc) respective. While these might seem rather wide for todays discerning SW listener or Ham operator, there is a reason for it in radios of this type. If the receivers passband were any narrower, the operator might pass over a suspect signal while scanning from one end of the band to the other, remember, this is not a communications receiver. Modes of operation include Diversity operation with two receivers, AM, FM, CW, and SSB. Built in crystal calibrators for 100kc, & 1mc. Dual, switch selected antenna input connectors, SO-239 for whips, and a BNC for external, a binding post for long wire antennas is also provided. Front panel connections include a BNC IF output, dual 1/4 inch covered headphone jacks, mic input, and recorder output, aux power input ( these last three connections are similar to those used with the GRA-71, GRC-109's, & PRC-64's). A panel meter provides relative indications of received signal strength, and battery condition. Front panel controls include a dual speed tuning knob, Narrow/Wide bandwidth switch, 10 position band selector switch, Push to Cal button, combination meter/calibrator frequency selector, a toggle switch selects external or whip antennas, RF, and AF Gain controls, variable BFO pitch control with OFF position, and separate miniature toggle switches for AGC/OFF, LIGHT/OFF, AFC/OFF, and AM/FM. The receiver is housed in a fiberglass water tight cabinet which is externally identical to the accessory case, both are 11.5h x 13.5w x 10.75d inches. In the center of each lid(receiver & acc case), there is a threaded mount to allow the use of these lids as a whip antenna base. The power supply, and tape recorders slide into a recessed area at the bottom of the receiver. THE POWER SOURCE, Several power supply arrangements and sources can be used with the set. The receiver proper, operates from 10-15vdc. Alternately a choice of two different power supplies can be mounted in a recessed area below the receiver, but in the same cabinet. The first is the battery power supply(PP-4833). It can accommodate either 8ea batteries BA-30("D" cells), or 9ea BA-42("C" cells). The second is the PP-4834/PRR-15 regulated power supply. It allows the radio to be operated either from 110vac of 50-400cps, or an external 24vdc source. Both power supplies are identical in size, and mount in the radio in the same way with no manual connection to the radio required(a connector in the back mounting area mates with the power supply). THE ANTENNAS, Two different antennas are supplied with the set. The first is a 3ft steel tape type(SG8788) having a PL-259 connector at it's end. Primarily meant to be used directly from the front panel connector of the radio, a right angle adapter is also provided to vertically postilion it. The second is a 9ft sectional whip, though it has it's own designation of SG8787 it is identical to the AT-271 whip antenna used with many other portable types. It can be mounted to the front panel in the same manor as the tape antenna using a supplied adapter, but the manual recommends that it be screwed into the receptacle provided on the equipment case lids. It can be seen that an antenna of this length could present an excessive load to a front panel SO-239 connector. Though the manual does mention the use of direction-finding antennas, and detector, as one of the radios modes of operation, there are none supplied with the set. And for operation with these types of antennas, the reader was referred to the "appropriate technical manual". THE TAPE RECORDER, Referred to as "Sound Recorder, Reproducer AN/PNH-5", this item has never been encountered with any other piece of equipment. It uses a non-standard tape cassette referred to as a "magazine" (this set predates the advent of the now familiar cassette tapes we all use). A double sided cassette, each side provides 30 minutes of recording time. It can be powered either by it's internal batteries ("C" cells, now we know why the receivers battery box has a dual battery type capability), or from the radios power source via a rather strange adapter cable that physically emulates the C'cells. Controls are included for REWIND/PLAYBACK/RECORD, ON/OFF, record & playback volumes, and a tape counter is included. It has only one connector for attaching it's external accessories, described as a 5-pin twist locking, and is similar to those found on the receiver. Connections for the headphones, mic, foot-switch(for pause control) are all made via this same connector using various adapter cables. The mic supplied with the set resembles an old commercial Sure communications mic, complete with PTT. The headphones were the common H-113, not my choice for comfort, or extended wear, and a foot switch is included for remote pause control. THE ACCESSORIES; Other than those items already listed, support equipment supplied with the set also included: (note, all of these items when contained either in the accessory case, or with the receiver, were all strapped to a standard Quarter Masters Pack board for field transport). CY-6237/PRR-15, accessories case. SG9349, Wire Antenna, 15ft, used alone or as a connecting cable for the remotely mounted 9ft whip. 52G3064, Wire Antenna, 50ft. SG8793, Power Cable, 24vdc, 15ft. SG8794, Power Cable, 110vac, 10ft. SG8790, Cable, Receiver, Recorder, coiled cord that provides interconnection between audio, and control circuits of the PNH-5 and R-1484. SG8791, power adapter cable used between the PNH-5 and R-1484. SG8817, Foot Pedal, Transcriber, used for remote pause control of the PNH-5. SG8792, Cable Interconnect, AN/PNH-4, allows the use of the PNH-4 recorder with the R-1484. SG7903, Cable, Dual Receiver, used when two receivers are combined for diversity reception. SG8818, Tape Magazines, for the PNH-5 recorder. SG9348, Cable Extension, Earphone. SG8796, Microphone. 17G3154, Battery Holder, for PNH-5. UG-146A, Adapter UG-924, Adapter UG-306, BNC, right angle adapter M359A, UHF right angle adapter DAGE 4752-1 adapter NS-7, Service Manual, Dictet Recorder (Keep in mind, and on the lookout for all these items, as I do not have them in my collection) SO WHAT'S THE MYSTERY? You might ask the above with all the info that has been presented. But we don't know anything about the life of this set. The questions are many. Who used it? Where? When? Was it used at all? Why, as the set seems such a viable one, was it not more prevalent, & used by the other services? Was it simply adopted as a "Stop Gap" until other designs then under development could be fielded? The serial number on my receiver itself is #77, while the one on the data plate of the receiver's cabinet is #19, this would let us think that not many were made, but I don't have other numbers to compare it to, and low numbers to quantities built are common with this type of equipment. Regretfully, as my main computer is down, I do not have access to a multi CD changer, thus I can't consult FEDLOG for more info, or to see if it is listed there. If you do, the FSN number for the set as shown on the front of the manual is 5820-082-5186. Any additional information about this set would be greatly appreciated. The next set to be featured as a "Mystery Radio" will be the GRR-5, then possibly the SCR-511/BC-745 (Pogo Stick), if you have any information about the use, development, or fate of these radios, please let us know. Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN military-radio-guy@juno.com *********************************** WHATSIT; HARP ? Dennis, I recently had several long conversations with Bob Graham and he brought up the subject of "did I know anything about HARP?" I was thinking this was the High Altitude Rocket Project of the 1950's but he said no, it was some semi secret program to bombard the upper atmosphere over the North pole with RF waves which will "burn up" any incomping missile. Have you ever heard of this? Bill Howard THE WILLIAM L. HOWARD ORDNANCE TECHNICAL INTELLIGENCE MUSEUM e-mail wlhoward@gte.net Telephone AC 813 585-7756 -------------------------------------------------------------- Bill, I ain't never heard of such a thing. Dennis ******************************* MEMBER PROFILE; Pete Williams Me... Without divulging too much. let's put it like this..I was too young to be a working part of WW2..[ 15 years old when it ended] and too old to be a part of any later skirmish which the government of the day had an interest obout. Early years were spent teaching- high school- but the continuing interest in electronics caused a shift in emphasis/occupation,so I ended up establishing a manufacturing enterprise in the newly discovered practical application of a device called transistor. A cultural engineering shock to say the least, but like all change, if one applies oneself, adaptability follows... let's face it , I'm typing this on a computer when only a few years ago I could hardly spell the word. Late in the '70's I established a business flogging ham gear/CB radios which flourished to the extent thatall equipment after a few years was professional test gear and goverment contracts.. ham radios and the like were relegated to lesser mortals. Ham radio?.. I have an interest still [got a ticket in 1949] but have pathetic interest in operating, and no longer an interest in rolling my own. There's no fun in reinventing the wheel. So, back in '88 I decided that life was too short to spend it working so sold my interest, sold the house, and bought a boat. lovely old thing she is/was, and sailed about the east coast of Australia and the near Pacific for 8 years. Tremendous life; great people with a kindred interest, and minimum stress. Of course , all this was done with the assistance of mywife who never got sea sick and pulled a mean halliard ! For the last 2 years wew have bought a house at METUNG on the lakes where we have a Herreshoff H28. The house has a TREMENDOUS workshop were the next love of my life takes a hold... Restorations. Ever since I cut up a BC - 453 Command rx, put 455 kHz in it , insalled it in my first car and powered it from a Japanese [ex WW2] dynamotor , Iv'e had pangs of remorse and want to make amends for the wrongs inflicted on historical communication artifacts! INTERESTS. My collection includes alot of WW2 gear , test equipment , and some post war stuff. The usual run of things such as BC- 348 BC - 312, ART-13, MN26, BC- 433. SCR 522 and later equipment such as GRC- 27, ARC-60 . -- not all complete as dispensers of this stuff appeared to be only interested in the heavy hardware which could be shifted with minimum of effort. The really important thing like controll boxes ,cables and plugs were forgotten. Last but not least is a Command tx rx setup, with the only thing missing is 3 tuning cables/ shafts to connect to the receivers. May be some kind soul has them lying underfoot and causing a disturbance! In all, my restorations and aims in collection are to maintain most any thing that came out of WW2. A su bsidiary interest is the avionic gear represented by the ARCseries. So that's the potted history as of today January 3 1998. email address is jupeter@net-tech.com.au My home address is METUNG, VICTORIA, AUSTRALIA I look forward to your info and please let me know if you need any further info. I will restrain myself at this time for asking for contact points for things like tuning shafts foe Command receivers !! Best wishes. Pete D. Williams VK3 IZ ******************************* HUMOR; A preacher was telling his congregation that anything they could think of, old or new, was discussed somewhere in the Bible and that the entirety of the human experience could be found there. After the service, he was approached by a woman who said "Preacher, I don't believe the Bible mentions PMS." The preacher replied that he was sure it must be there somewhere and that he would look for it. The following week after the service, the preacher called the woman aside and showed her a passage which read, "And Mary rode Joseph's ass all the way to Bethlehem." ------------------------------------------------- Two Arkansas rednecks, Bubba and Earl, were driving down the road drinking a couple of bottles of Bud. The passenger, Bubba, said "Lookey thar up ahead, Earl, it's a DPS roadblock!! We're gonna get busted fer drinkin' these here beers!!" "Don't worry, Bubba", Earl said. "We'll just pull over and finish drinkin' these beers, throw the bottles under the seat, and peel off the label and stick it on our foreheads". "What fer?", asked Bubba. "Just let me do the talkin', OK?", said Earl. Well, they finished their beers, threw the empty bottles under the seat, and each put a label on their forehead. When they reached the roadblock, the trooper said, "You boys been drinkin'?" "No, sir", said Earl. "We're on the patch". ******************************* EDITOR; Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN military-radio-guy@juno.com --------- End forwarded message ----------