Military Collector Group Post
(14 pages) Index: BC-620, -659 OVERVIEW; Ed Guzick MEMBERS WRITE; BC-620/BC-659 Rebut SCR-284(BC-654); by Dennis Starks SCR-536(BC-611); What's the Scoop Dennis? RADIO FACTOIDS; SCR-195 in Italy 1943, BC-611 canvas bags? by Hue Miller, and Dennis Starks MEMBERS WRITE; BC-222,-322 With Korean War FAC's? More On The BC-611 Canvas Bag; From John Kid BC-474/SCR-288,GUESTION ANSWERED. **************************************
BC-620, -659 OVERVIEW; Ed Guzick Dennis, I wrote this for an individual
but maybe it could be put in a post? It would certainly give you something
to pick apart!?! HI Awaiting your comments. Ed A not too detailed overview
of the BC-620/BC-659 It is usually difficult separating the real story
from the printed history, which is true of the WWII FM vehicular radios.
Being close to some of the participants and reading between the lines
I can not say with certainty as to how I would write this history (as
if anyone would care). I spoke to one of the few technical survivors of
this era and was told, "I can't remember!" I understand his comment as
I certainly can not recall any events in detail from 50 plus years ago.
In reviewing the information on hand, it appears that Dr. Daniel Noble
(1902-1980), a professor of electrical engineering at the University of
Connecticut, using Armstrong's FM patents, designed and began testing
FM mobile communication's for the Connecticut State Police in Hartford
during October 1939. Built by the Link Radio Corp., New York City. The
results -complete two way coverage over 25 miles of hilly terrain- were
beyond expectations. In 1940, Connecticut contracted with Link to supply
equipment that would cover the entire state. The Hartford system demonstrated
just before WWII that FM communications were possible; Link designed and
produced many of these pioneering units. During the test, officers and
engineers from the United States Army Signal Corps, Fort Monmouth, N.J.,
journeyed to Hartford to inspect the Link equipment. Present were the
men of the driving force behind the use of FM mobile radios by the U.S.
Army ground and air forces and the Marine Corps. Link sets became standardized
in 1941 as the SCR-293, transmitter receiver and SCR-294, receiver only.
They were the first FM sets used in combat and the first in North Africa.
Interestingly, they were experimental and never intended for the field.
Due to the exigency of the times, they were placed into production. The
Galvin Manufacturing Corporation (Motorola) began operation in 1928 with
the purchase of the bankrupt Stewart Storage Battery Company in Chicago.
By 1936 they announced an AM mobile Police Cruiser receiver and in 1937
produced Station transmitting equipment for the police communications
market. By 1939 Galvin Manufacturing introduced its first two-way radio,
the T69-20 mobile transmitter and companion Police Cruiser mobile receiver.
It was an AM set designed for the FCC-assigned police channels 30.5 to
39.0 megacycles. In June 1940, Nobel -by then a leading authority on frequency
modulation- was persuaded to spend a six month sabbatical at Galvin Manufacturing
to assist in the design of a line of commercial FM two-way products. The
company established a communications department, and Noble remained with
the company as director of research. In 1940, Galvin Manufacturing developed
the first AM hand-held two-way radio Handie-Talkie. The initial order
of Handie-Talkie radios was for 3,500 units. By 1945 the company built
137,031 (an additional 4,500 subcontracted to Electrical Research Laboratories).
In 1942, four manufactures attempt to design a radio to meet the Signal
Corps specifications for a high-frequency portable radio: Hazeltine, Wilcox-Gay
(using AM), Philco and Galvin (using FM). Dan Noble's design of a portable
FM two-way radio, the 35 pound SCR-300 backpack, wins for Galvin Manufacturing,
inheriting the name "Walkie-Talkie", and replacing an older Signal Corp
radio (SCR-195?). The company manufactured 46,911 and Philco produced
an additional 8,000 under subcontract. Developed by the Signal Corps Laboratories
and built by Galvin Manufacturing in 1942 are other FM communication products.
The SCR-509, 510 (BC-620) and the SCR-609, 610 (BC-659). The company built
34,127 SCR-509/510 series, and subcontractor Continental Radio and Television
(later known as Admiral) produces 7,710. The company builds 62,496 SCR-609/610
series while subcontractors Continental Radio and Television and Belmont
Radio Corporation produce an additional 13,899. The SCR-609 was tested
in January 1942 but production did not reach the field until 1943. I could
find no dates for the SCR-509, however the beginnings of both go back
to 1940 and the Signal Corps Laboratories with the SCR-509 being slightly
older of the two. It is entirely possible that both the "500" and "600"
series were designed and built concurrently or nearly so. The first demonstration
of FM before an all military audience was 16 NOV 1939 of a LINK police
transmitter and receiver. At this point I would ask what ever happened
to Link Radio Corp? From: Motorola during World War II, IEEE Spectrum
Sept. 1987, The Signal Corps: The Emergency, TM 11-615, TM 11-605 WWII
Vehicular FM transceivers In atypical retrospect, it is difficult for
me to understand today why two nearly identical transceivers were built.
In size and weight they are identical with only a built in front speaker
on the BC-659 being the obvious physical difference. Initially, the SCR-509/510
was developed for Armored units while the SCR-609/610 was tailored for
the Field Artillery. Obviously both found their way into other applications
but are undoubtedly most identified with the WWII jeep. The number of
crystals and availability was certainly a most significant part of this
decision. The receiver is superhetrodyne crystal controlled and operates
on two channels using internal crystals. The transmitter has an output
of 1.3 watts and is VFO in operation but held on frequency by the receiver,
which detects the signal -in the discriminator- and corrects for oscillator
drift. On the front panel are a meter, phone and mic jacks, and three
controls, on/off volume, channel A/B and a meter control switch. Only
the volume and channel select are operator functions. The control switch,
is used with the meter to measure B+, filament voltages and is used when
tuning the final. Component breakdown SCR-509 ground transportable SCR-510
vehicular BC-620 20.0 - 27.9 mc transceiver CS-79 dry battery case PE-97
power supply, 6/12 VDC input AN-45 antenna w/threaded mtg hole FT-250
mount FT-317 mount Channels 80 @ 100 kc spacing SCR-609 ground transportable
SCR-610 vehicular BC-659 27.0 - 38.9 mc transceiver CS-79 dry battery
case PE-120 power supply, 6/12/24 VDC input PE-117 power supply, 6/12
VDC input AN-29 antenna w/threaded stud FT-250 mount FT-317 mount Channels
120 @ 100 kc spacing The frequency range and number of crystals are the
major difference between the 500 and 600 series. The ground transportable
(luggie-talkie ?) included the battery case CS-79 which is the same size
as the power supply. The three components could clip together on the mount.
All of the power supplies are interchangeable. The FT-250 is a shock mount
for the transceiver and power supply which clip together using the built
in spring clips. The FT-317 was used for individual mounting of each component
part. The TS-13 handset, HS-30 headset and T-17 microphone were included
with each set. Note that the antennas had different mounting arrangements
preventing the antennas from being switched. Although I don't think the
slight difference in length would make an appreciable difference in operation.
There are other less known parts to these systems but are not included
here as they are not necessary to the basic description. A complete article
would of necessity be so long that it would become boring. However, this
story can certainly be elaborated upon and I'm hopeful someone out there
will do just that. Repair and restoration is relatively easy. I have worked
on three units and the difficult part was rebuilding the dried cracking
cable. The capacitors are few and well made. I found no obvious defects.
Alignment requires no special equipment as everything needed is built
in. Several power resistors in the supply were replaced as the leads corroded
at the resistor body. The frequency is partially on the present day 11
meter band. I'm not up to date but I understand FM operation is now allowed.
MEMBERS WRITE; BC-620/BC-659 Rebut, Dennis, A little rebuttal to your comments on the BC-620, BC-659 story. The name "Motorola" was coined from the combination of the two words Motion and Radio. - - - - - - - - - - - - - - - -
Close, but the company historian states that the idea was to signify "Music in motion". Motor for motion and a popular suffix of the 20's and 30's for radio/phonograph was "ola" as in the famous Victrola. The initial order of 3500 BC-611's from Galvin were never received. This order was diverted to the Dutch East Indies. - - - - - - - - - - - - - - - - -
And straight into the hands of the Japanese, says history! The original SCR-300 submitted by Galvin for Signal Corps testing was not FM. It was originally AM, and was re-designed for FM at the Signal Corps insistence. - - - - - - - - - - - - - - - - - -
Very interesting! This does not show up in any of my stuff. But I read that it was developed by Galvin Manufacturing in "cooperation" with the United States Signal Corps. BTW, It is possible that I know of an original AM SCR-300. A mess of photos and a write up would be nice. That's up to the owner, however! Thanks for posting the story. I'm surprised and glad that it was well received. Ed Guzick ed)The moto-rola quote/name origin was from "Timeline of MOTOROLA HISTORY" a large wall mounted poster put out my Motorola last year that chronologs their acheivements from 1928 to present. Perhaps their historian should read their own material. The original Galvin SCR-300/AM item does appear in "The Signal Corps". Why you think they were so hot to get their hands on Noble? ***********************************************
BC-654/SCR-284 QUESTIONS ANSWERED. by Dennis Starks Dennis, What was the BC-654 used for? I know it was a WW-II feild radio,& that's about it. Fred, ================================================================ SCR-284 (BC-654) The SCR-284 was the first *Field Portable* radio set to be adopted by the U.S.Army as a Standard item that was capable of both CW,& AM phone operation. Development began before the beginning of WW-II, however the first 31 production sets were not delivered until June 1942. Thus it's first battle-field use began with Operation Torch ,the North African invasion of November 1942. The SCR-284 subsequently saw service in virtually every theater of WW-II. Though obsolete by wars end,the SCR-284 continued to serve at least in a training capacity until after the Korean Conflict. Originally designed for use by Infantry,Field Artillery,& Tank Destroyer units. The SCR-284 could be operated as a field set with it's hand crank generator, as a vehicular radio with a dynomotor power supply, or as a simi-fixed station using a gas powered generator. It's primary duty as a field Man-Pack system was greatly hampered by the systems total weight (250 lbs). Though intended to be carried by three men,closer to six were required. This much to the dismay of the radio's users. Additionally the troops complained of the excessive noise produced by the hand crank generator saying,"it inevitably drew Japanese gunfire". As a vehicular set,it was widely installed in Jeeps,Command Cars, & Half Tracks. Before wars end the SCR-284 was replaced by the much smaller,& more rugged SCR-694(BC-1306). This set,though primarily designed for use by Airborne & Mountain troops,was used as an expedient replacement do to the SCR-284's failings. Frequency range; 3.8-5.8 mc,in one continuously tunable band. RF power output;20/5 watts CW,5/2 watts AM,(high/low respective). Antenna Types; 15(field & vehicular) or 25(field) ft whips. Or any standard wire type for field or simi-fixed station use. Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN *********************************
SCR-536(BC-611); Dennis, What the real scoop on the BC-611? I've seen the propaganda put out by Motorola on it & the BC-1000. Also the BC-1000 scoop would be nice. Fred --------------------------------------------------------------------------------------------
Fred, The Motorola propaganda that you mention is a real sore subject with me. For those that don't know, it takes the form of an Info-mercial & was printed in a multi page article in various trade publications starting a couple years ago. The reader, thinking all along, this is some interesting stuff, neat to know history. Doesn't realize until he has finished reading that it's all just a big add. Then if he doesn't know any better thinks it all to be true. In fact it's full of BULL SHIT with just a little truth thrown in. Upon reading it, I wrote numerous nasty letters to both Motorola & all the publications that were printing it. Don't know what good that did! None of these letters netted a response. In this printed Bull Shit, Motorola claims complete credit for the design & development of the BC-611, BC-745, BC-1000, & FM! The later two subjects are the most disturbing. While it is true that Galvin did tour europe just prior to WW-II, & he did envision a major storm brewing that would require lotsa radios. And he did return home to begin development on these sets. But that is about as far as it goes. Without the aid of the Signal Corps, none would have been suitable for Military use. In the case of the BC-1000 & FM, Motorola also claimed to be the pioneer that made FM possible, & claimed credit for it's development, that of & the BC-1000, & just about every FM radio built till this day. They at no time mention Armstrong(the greatest man of all time), nor August Link. Both these men were needed to make the BC-1000 work, & the patents DONATED by Col Armstrong to his country in the time of most urgent need. Nor is it mentioned that the first BC-1000 submitted to the Signal Corps for evaluation by Galvin was not FM at all, but AM. It was re-designed at the insistence of the Signal Corps, at which time the help of Col. Armstrong & August Link was enlisted. These men, working around the clock, hand built in their own home garage/work shops, because their manufacturing facilities were completely swamped, many of the FM prototypes & even pre-production radios, that went on to change history & radio forever! Fact is, August Link was building FM radio before WW-II, & Galvin was swayed only because of the governments insistence. Then after the war, Galvin/Motorola capitalized on all that free engineering & patent access. Are you yet sorry you asked? I suppose I should now get off my soap box, because this could go on for a very long time. Suffice to say, it was Armstrong(a true American Hero) that invented FM, & it was Link that made it happen before ANYBODY else. The below is extracted from a plaque that I put on display with the BC-611 when I'm on tour. It will save me some typing, & I'll include some further remarks at it's end. The BC-1000 on the other hand deserves an entire volume, so will be addressed another time. Originaly designed for use by Paratroopers, the SCR-536 was the first true hand held transceiver, & the second radio set to be called the Handie Talkie. Being the most familiar military radios of all time,it is often refered to as the "John Wayne Radio". First introduced to the U.S.Army by Galvin Corp.in February 1940,an intial order of 3500 units took place later that year. However these first sets were diverted by Galvin to fill a Dutch contract. This probably do to their impending attack by Japanese forces in the Dutch East Indies. It's first battle field service began on the beaches of Operation Torch(the North African Invasion of 1942). Subsequently,the SCR-536 saw service in virtually every theater of the war by all combatants. In the case of the latter, examples of the radio captured in Sicily were judged by their new German owners as"extremely effective","ideal equipment for forward observers & companies". Japanese admiration was expressed by their post war cloneing of the set as the JBC-611. It is strange that in light of this enemy admiration, no veteran that either used, or serviced the set had anything good to say about it with the exception of,"it was good for talking from the bottom of a hill, to the top". Use of the 536 continued in U.S. hands until it's successor (the PRC-6) could be fielded in quantity,approx 1952. International Allied use continued until the early 1960's, aided by CIA proliferation under the counter to various groups all over the world. Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN email@example.com *********************************
RADIO FACTOIDS; SCR-195 in Italy 1943, BC-611 canvas bags? by Hue Miller, and Dennis Starks Here are a couple radio factoids i noted in an afternoon book shop prowl in dankest oregun ( perfect bookstore weather, grey from ground to heaven, steady heavy rain. that's why the northwest is deservedly reknown for being a very literate region. ) i again looked at the Time Life WW2 book "The Italian Campaign" and the cover illustration has a USArmy infantryman wearing what appears to be an SCR-195 "in the approach to the mountain fortress of Troina, during the campaign for Sicily". This would be 1943. The photo, very dark, is from the rear and the two section bag is visible, also the substantial AN-29 telescopic antenna, and a telephone handset. BTW, the end cap on the AN-29-C, does it attach to the bottom section of the antenna by a small chain? because it looks like some little object hanging from the first section of the antenna and i would guess this is the end cap. Also btw, this would indicate that the Army by this date was already doing what we are mostly forced to do today: substitute later suffixes of the AN-29 for the earlier one originally specd for the SCR-194/195. Also, in Infantry Journal -i believe it was - i saw a grainy photo of some airborne troops inside a plane on D-Day. 2 men were with BC-611, carried at the top of a chest pack horizontally, at about shoulder level. What was of interest to me was, no canvas bag on them. ( There is a supposed paratroop padded bag for the BC-611. I don't think it appears in the WW2 issue manuals. ) One talkie also seemed to be painted on the side with some large characters, M-3 or some such type thing ( hard to make out exactly). and this reminds me of the BC-611 i saw in the northwest that had been found in a ditch, antenna broken off, by a dutch boy, after the battle of Arnehm. It has a simple camo pattern of dark brown paint in three stripes winding up around the set, the bands of the stripes maybe 2-3 inches wide. The finder still owns it, having replaced the antenna. He also found a bazooka, which he enjoyed firing. hue miller -------------------------------------------------------------
All the AN-29 series antennas are identical except for an insert in the bottom that changes the thread. 1/4 x 20 for the SCR-194/195, 3/8 x 18 for the BC-620/659, 3/8 x 24 for the early SCR-300's. The Cap & chain are located at the top of the antenna's first section, same with the AN-30, which is the antenna used with the SCR-195. The AN-30 is cosmetically different than the AN-29's, though it's collapsed length, & the threaded insert are the same, it's overall extended length is shorter because of the higher frequency range of the radio it was used with. As a result, the diameter of the first section is also smaller do to fewer antenna sections. I have seen some AN-29's that were expertly shortened, & had 1/4 x 20 threads, I can't testify if these were Signal Corps modified to sub for the AN-30, or a later civilian mod, especially as 3/8 x 18, & 3/8 x 24 examples have also been found in the same condition. I have often fought the cause of the actual wartime use of the SCR-194/195, but I was not aware of it's use in Italy. But this is not surprising. When Allied forces reached the Italian mountains, the communications equipment in hand was found to be too heavy, bulky, or fragile for transport and use in this terrain. As a result, a blanket "Urgent" battlefield request was sent back to the States to immediately search out & ship all the available old Cavalry, or mule/horse carried equipment in the Signal Corps warehouses. Thus the SCR-194/195's might well have been thrown in. The canvas bag for the BC-611 is a bit of a mystery. I suspect it was only really included with AN-190 DF antenna & it's conversion kit, especially as this is the only way it ever appears in the manuals. After Operation "Torch", the Allied invasion of North Africa in 1942, a complete re-thinking of radio packaging took place. As this was the Army's first experience with a large scale marine landing, there were many lessons learned the hard way. Much of the equipment reaching the beach was inoperable do to either being submerged in water, or from salt water seepage into the radio equipment from spray. The Signal Corps began to develop canvas covers, and bags to protect it's equipment in future landings. In the case of the BC-611, the Signal Corps found that a standard weapons bag (for the 30 M1 carbine), did an excellent job, and even allowed the radio to be used while contained in it. This method of protection became very common as can be seen in many surviving photos. The canvas bag for the BC-611 was first described in the original manual supplements for the SCR-536 which also contained the DF conversion kits. Though many have said that this DF set was designed especially for the "D" day invasion, I find this hard to believe. I would sooner think that this addition was designed "as a result of the D'day invasion". Contrary to popular dogma, the DF antennas for such radios as the BC-611, & PRC-6 were not intended to be used in the locating of enemy transmitters. They were meant to be used by small units to locate where "they" were in respect to their higher echelon. As we know, many assaulting forces did not end up where they were suppose to be, both in the beach, and airborne landings of the "D" day invasion, or even later in the case of airborne troops in operation "Anvil" in southern France. Nor did these poor soles have any idea where they where for considerable time. In the case of the inland airborne troops, they began a frantic search for street signs, villages names, or any recognizable landmarks that would identify their location. Those displaced units on the beach were in even worse shape. Thus we can see why the need for a direction finding set would result from this experience. And with this direction finding modification for the BC-611, it's associated carry equipment, I/E canvas bags. Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN firstname.lastname@example.org **************************************
MEMBERS WRITE; BC-222,-322 With Korean War FAC's? I've been working with the Mosquito Association, which commemorates the mobile forward air controllers and airborne spotters during the Korean conflict. They had the risky job of controlling close air support for ground troops in Korea. The guys in the "Radio Jeeps" would drive right up to the front and look for a place where they could see the action without being immediately nailed. They would then guide unarmed T-6 "Texan" trainers, pressed into spotter service, onto the scene. The T-6 crews would spot for the attack aircraft. The ground controllers also guided C-47s in to drop supplies for the engaged units. One of their members gave me a copy of their terrific book, "Mosquitos in Korea." On page 166 there is a photo of one of the radio jeeps. An officer is standing next to the right front fender and talking into a radio sitting on the hood. The radio is a BC-222! (or maybe -322; they look alike). I had thought the old 222 long gone by this time, but the caption reads: "TACP Radio jeep in use at forward control point, 1952." Just goes to show-- you use what you can get! 73 DE Dave Stinson AB5S email@example.com ed) It is very highly unlikely that the BC-222/322 wound have seen service in Korea especially in an FAC capacity. If it were, it's users would have been severely handicapped. Experiments where conducted in 1936-37 using the BC-222 in small aircraft for the purpose of "Artillery" spotting, and it had been planned to use the radios in this capacity. But with the advent, and subsequent testing of the BC-620/659 series in this same role, the idea was scrapped and the BC-620 took it's place just as with all ground applications. This began a trend of using backpack radios in spotter aircraft which continued till late Vietnam era. Several facts would prevent the BC-222 from being used in Korea. #1 Neither they,nor their special battery survived in production even till mid WW-II. so there would have been no support for them. #2 there was nothing in inventory, during either WW-II or Korea that would talk to one except another like unit(maybe a Navy TBY), so if communications from ground to aircraft were intended, one would have needed been mounted in an aircraft(bad idea). It is far more likely that the picture itself is severely out of context/time/place(very common). Or the radio in question is actually a TRC-7 which from an extreme distance in a very bad picture, might be mistaken for a BC-222. They were similar in size, the battery attached in the same manner, and the front panel was likewise down the front of the radio. Dennis ***********************************************
More On The BC-611 Canvas Bag; From John Kid Dennis, In Shelby Stanton's book "US Army Uniforms of WWII" there is a photo on the front cover, of a paratrooper with a BC-611C, in a rigger made webbing cradle. This photo is I think from operation "Torch". There is a mating photo with a better view of the webbing taken from the rear quarter, and he is not posing as if he's talking on the set, as in the Stanton book. The cradle would have been devised "inhouse" by necessity as you couldn't jump with a BC-611 slung over your shoulder with it's strap. The webbing obviously allowed use without "unpacking" the set. Necessity is the mother of invention. John A. Kidd Collector: Military radio. Tullamarine, 3043. Interests: Military aircraft Victoria. AUSTRALIA & vehicles, Chrysler cars. ------------------------------------
John, While jumping with a BC-611 over the shoulder would indeed be a trick, how about with a BC-745? A vintage photo exist showing an airborne troop holding a Pogo Stick out in front of him, two handed, at almost arms lenght, he is demostrating his jump/landing posture. Another photo shows cramed troops aboard a C-47 ready to take off, the upper part of a Pogo Stick is bearly visable. Dennis *********************************
BC-474/SCR-288,GUESTION ANSWERED. Dennis - Recently I acquired a BC-474 radio and I was wondering if you knew any of the history of the radio and for what purpose it was used. I am very familliar with other field radios used in World War 2 but this unit is one of the only ones of its type that I have seen. I got it at a garage sale, and it looks like it was stored in a cool dry area as the cables are still soft and the physical appearance looks excellent. The BC-474 looks like a field portable or vehicle type unit, perhaps predating the BC-611. The unit is in a small green metal trunk type case of dimensions about 8 inches higy about 10 inches deep by about 19 inches long. The case has D-rings and other clips so it appears the radio could be lashed to a pack frame or maybe a vehicle. The unit has a separate transmitter and receiver built into the same case. It lloks like there is room for batteries for the receiver in the case. The unit also included a filter (FL10) which plugged into the power cables, presumably for a generator. The unit appears to tune from 2-6 MHz with both phone and CW. It uses large 1 volt tubes in the receiver and 4 6V6 tubes in the transmitter. Your comments, please. Best regards, Jim Karlow --------------------------------------------
Jim, Why am I always hearing about people gettin stuff at garage sales. Don't happin in real life. Sheldon just sent me a desturbing message of a large cache of command set stuff he got at a local garage sale, instead of going to the same hamfest I did. I/E he drove 5 miles & got a ton of goodies, I drove 400 & didn't get squat. It ain't fair! If future, if anybody gets somethin neet at a garage sale or road side flea market, I don't wanna know about it! Most especialy if it's somethin I ain't got & can't have! Just tell me you got it, not where. Your BC-474 is one of the most historicaly neglected radios in existanse. It ranks right up there with the MAB,DAV,RBZ etc. However,luckily some tidbits of info have been located on it, so we can in large part correct this historical neglect. The following is an extract from another book in the works which is part of the same series as the PRC designated equipment. I should add here,that several noted authorities have said in print,that the BC-474 didn't see any combat service, rather it was relegated to training purposes. As can be investigated by the reader via the referanses at the end of this artical,this is absolutely not true! BTW these referanse numbers are the same as those used in the PRC equipment list many of you already have. SCR-288;Field portable man-pack transmitter/receiver. The SCR-288 was adopted as a "stop gap" set to temporarily replace the SCR-131,161,171,for use by Field Artillery,Infantry & Signal Companies. This until sufficient quantities of the SCR-284 could be fielded. The SCR-288 from the onset did not meet Signal Corps standards,however the set was already in production by RCA for the Swedish government(circa 1940). Thus all manufacturing,supply,& logistics bugs were already ironed out. The first five sets were delivered in March 1941. Designed as a man-pack set for carry by two men,the main component of this system(BC-474) shared common parts,& circuitry with other equipment being built by RCA,including their AVT & AVR series which were used in small aircraft. Though this little radio set was only adopted as an expedient,it saw significant service in WW-II even after it's successor,the SCR-284, became available. Most notably with Filipino Guerrilla forces,the China/Burma theater,and in the North African,& Italian campaigns,not to mention with various Allied countries(who all favored it's small size & extremely simple operation). Do to this small size,& weight(71lbs system weight/2 man carry verses the 250 lbs/3-6 man carry of the SCR-284),the SCR-288 was not truly replaced in many applications until the much more rugged & advanced SCR-694 became available late in the war. The only competitive system of it's time was the excellent Navy TBX series which had been in service since 1939. This set however was complicated to operate,& it's extreme versatility sacrificed portability. Even after the introduction of the SCR-694,the SCR-288 continued to serve in the training of Signalmen at home. The SCR-288 was the first radio set of it's type to be adopted that was capable of AM phone operation(though as a"Stop Gap",Limited Procurement,& later as a Limited Standard). The system sacrificed several attributes in favor of light weight,small size,& simplicity which in the end spelled it's success. These were mainly ruggedness,& versatility. In the case of the latter,the SCR-288 could only be used as a field set,being powered by a hand crank generator & dry battery(for receive). No alternate power supplies or ancillary equipment are known of that would have allowed vehicular or simi-fixed operation as with it's successors. Too,it could not use a wide variety of antennas,being restricted to a 35 ft wire type. Other failings are do mainly to the available technology of the time,which progressed rapidly during the course of the war. Thus it's demise when industry & logistics could catch up with this new technology. Operation was;transmit 3.5-6.3mc AM/CW in one continuously tuneable band,with an RF power output of 4 watts. Supply voltages of 6.6v/1.65a(heaters),& 290v/100ma(plate) were provided by a hand-crank generator. Receiver operation was 2.3-6.5mc AM/CW in one continuously tuneable band. Supply voltages of 1.5v(heaters) & 90v(B+) provided by a dry battery or hand-crank generator. System components include;BC-474 transmitter/receiver(18 x 9.5 x 7.5"). GN-44 hand-crank generator,with 2ea GC-7 cranks,2ea LG-3A legs,LG-2A seat/leg,CD-125 power cord,generator canvas bag,legs roll bag,& FL-10 filter. BG-128 canvas back-pack bag(for BC-474 & acc),HS-30 or equivalent headphones,T-17 or equivalent mic,CW key,BA-48 dry battery,4ea legs(for BC-474)....................Ref.#1,6,19A,B,C,23,30 Dennis Starks; Military radio Collector/Historian ********************************************************
(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, firstname.lastname@example.org)
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