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Military Collector Group Post Backmail #59 (12 pages) Index: COUNTERMEASURES/SURVEILLANCE RECEIVERS; From Spencer
Bahner & Dennis Starks MEMBERS WRITE; More R-1444 TRP-4, MYSTERY JAPANESE
GREEN RADIO; From Breck Smith AN/URC-100 SERIES; Part I, by Richard Lacroix
PRC-74 SELECTABLE SIDEBAND; Jim Karlows Contribution RBS RUMINATIONS;
By Hue Miller NAVY RBM SERIES; ***********************************************
COUNTERMEASURES/SURVEILLANCE RECEIVERS; Dennis, I am looking for a couple
relatively recent solid state mil receivers: AN/URR-69 or R-1444/UR HF
receiver and R-1518/UR Vhf receiver I also have a dumb question for the
mail list group. Here goes: How exactly were 'countermeasure' receivers
used? Many of these Rxs were manually tuned and would have been difficult
to use to find 'hostle emitters' under combat conditions- was that how
they were actually used or am I missing something. I guess that role would
have been OK for units in a stand-off position (like naval vessels or
land based support facilities) but I am unclear on details of military
useage of this kind of surveillance receiving gear. Feedback? Thanks,
Spencer Bahner spencer12345@classic.msn.com ---------------------------------------------------------------------------------
Spencer, There has always been several different varieties of "Countermeasures",
or "Surveyance" receivers each having a different intended purpose in
life. And with these different purposes, there was a correspondingly different
type receiver used. Some of the purposes are as follows. #1. "Intercept"
receivers, to detect, monitor, and derive intelligence from enemy traffic.
In this capacity we have a fair quality communications receivers usually
used in a fixed location. Located far remote, and usually on a different
continent than the subject signals being analysed. Beginning in WW-II
a series of Hammerlund designed radios were used almost exclusively in
this role. They included the BC-779, BC-794, R-270, BC-1004, etc. All
these receivers were physically identical, differing mainly in frequency
coverage. Used in conjunction with each other in systems like the SCR-244,
and FRR-12, it is to their credit that the cracking and daily decoding
of both German and Japanese codes can be attributed. Later came such receivers
as the R-274(SP-600), and R-274D(SX-73), which could cover the entire
spectrum between 500kc and 54mc in a single package. With this increased
frequency agility also came the ability to use a single type receiver
to performed the tasks of other intercept/monitoring/communications duties
that previously required a host of different types of equipment employed
in as many different capacities. #2. To analyze and derive intelligence
from the enemy signal itself. On the HF bands, quality receivers that
might have included a Panoramic indicator like the BC-1303, or the exotic
Navy RBY which was an SX-28 with an integrated panoramic adapter. Not
restricted to intelligence operations, receivers of these types would
also perform the functions of spectrum management, or general communications,
and monitoring. On the VHF/UHF bands, the APR-4, and APR-5, or the Navy's
RDO, or RDZ might be used. They were used to detect, analyze, and locate
enemy radar as well as other signals. In the case of these, the band pass
was purposely wide to both pass the wide radar pulse signals they were
to detect, and to allow fast manual tuning or "scanning". Much of the
very exotic and specialized Watkins Johnson equipment found today had
a similar purpose in life as the receivers noted in this category. #3.
Dual purpose Surveyance, of either enemy, or allied traffic. Closer to
the front lines, receivers like the BC-787, Hallicrafters S-27, or S-36(the
famous "UHF" receivers) were used to keep track of enemy movements. Capable
of operation between approx 27-120mc, either AM or FM. These receivers
were used to monitor tactical enemy traffic, usually of armored columns,
providing information on troop movements, and concentrations. But every
bit as important was their use to monitor friendly traffic. Patton himself
kept an S-36 close at hand as it was his best source for up-to-date information
on the problems or fast pace progress of his own command. Intelligence
operators also used this equipment to insure that proper radio doctrine/security
measures were being observed by troops in the field. #4. Direction finding.
Also in close proximity to the front lines were the direction finders.
They might include systems like the WW-II SCR-255(BC-903), SCR-503(BC-1003),
or the postwar R-395/PRD-1, and a host of others. Each considered to be
field portable(a very loosely used term to say the least), they were used
for the spot location of either friendly or enemy transmitters. All these
receivers were provided with a rather broad IF bandwidth, and fast tuning,
both to facilitate faster manual "scanning" of the frequency spectrum
minimizing the chance of inadvertently passing over a suspect signal.
You might note, that while the R-395 was grossly obsolete shortly after
it's introduction, it received widespread use in Vietnam, and was still
listed as a current issue item until about 1983. A step down from the
above would be the real close in direction finders, like the SCR-504(famous
suite case receiver), or the Navy DAG. Both used to narrow down the location
of an enemy or clandestine transmitter to within a few yards. Beginning
in the late 50's, and progressing into the late 70's, there was an ernest
attempt to develop, and adopt a receiver, or set of receivers to replace
the monster R-395. Until such receivers as the R-744/PRR(VHF), and R-901/GR(HF)
appeared in the late 50's, systems actually billed as "test equipment"
would see "stop gap" use in direction finding. These referred to as "interference
measuring and detection sets" they were mainly built by Stoddard and other
companies usually associated with test equipment. Included were the R-178/URM-3,
NM-50, NM-52, and a host of others. While some were very complex in the
array of antennas and accessories they included, all were blessed with
the same wide bandwidth and fast tuning of their predecessors. While the
use of these varied "Test equipment" types continued possibly as late
as the early 80's, the 60's saw a steady succession of experimental receivers
interring the field. Like the R-1410XE(solid state VHF), though still
having experimental nomenclature, it is possible that it was built in
sufficient quantities to actually have seen service in the field. Or the
R-1218(XE-3) of 1968 which would actually be adopted and included with
the R-1518(it's VHF twin) in the TRQ-30 set. Possibly the first truly
portable, solid state direction finding system to receive official adoption.
At the same time came the R-1484/PRR-15 possibly only adopted by the Marine
Corps out of desperation or impatience with the dilly dallying of the
other services. Desert Storm saw the use of commercial "Scanners" built
by AOR, and capable of HF/VHF/ and UHF multi mode operation. Possibly
only acquired as an expedient, they were bought up by the military in
such quantities that the civilian market suffered greatly. The R-1444
on the other hand, does not really fit the niche of a direction finder.
While it is certainly capable of direction finding, I'd sooner category
it as an auxiliary receiver intended to be used in the same role as or
possibly even as a replace for the GRR-5. I hope that I've answered some
questions, and posed some others without thoroughly confusing everyone.
Dennis Starks; MILITARY RADIO COLLECTOR/HISTORIAN military-radio-guy@juno.com
*********************************************** MEMBERS WRITE; More R-1444
More R-1444, Hi Dennis, I must respectfully question your remark that
compares the R-1444 to an "auxiliary receiver", ala the GRR-5. As a proud
owner of one, let me point out the specs: 0.5-30 MC in 100 Hz steps, all-mode
(AM, USB, LSB, CW, and *FM*), 3 IF bandwidths (1, 4, and 25 KC), sensitive,
small, portable, 3 power options. Has a 'recorder' output (fixed audio
level). Has 50 ohm or whip antenna connections. Has a 'scan' selection,
which mechanically multiplies the tuning rate by a factor of 10. RF gain
with AGC setting, and a tiny signal strength meter. The front dial glass
is shielded (to keep radiation in, I assume). Call me crazy, but that
sounds like a fairly high-end portable intercept receiver to me. Pete
ed) the more you describe your R-1444(another radio I don't have, and
want), the more it does sounds like a universal axillary receiver. Possibly
even intended to replace the GRR-5(as that is what this receiver was meant
for and no other known receiver ever replaced it). As noted in the article,
there is a big difference between an "Intercept" receiver, and one intended
for DF work. Also note what I wrote "While it is certainly capable of
direction finding", " I'd sooner category it as an auxiliary receiver
intended to be used in the same role as, or possibly even as a replace
for the GRR-5". Also note the word "Possibly"! Just for the sake of argument,
let us compare the R-1444, and the GRR-5. R-1444, sensitive, small, portable,
3 power options. GRR-5, small(for it's day), portable(for it's day), sensitive,
"5" power supply options. R-1444, Has 50 ohm or whip antenna connections.
GRR-5, Hmm, it does too. R-1444, 'scan' selection, which mechanically
multiplies the tuning rate by a factor of 10. GRR-5, Me too! R-1444, RF
gain with AGC setting, and a tiny signal strength meter. GRR-5, RF gain,
and AVC I got. But no tiny meter, shucks! R-1444, Has a 'recorder' output
(fixed audio level). GRR-5, I ain't got this either, but neither did any
other receiver until 1968. Jane's 1981 describes the R-1444/URR-69,"It
is used either as a general-purpose receiver or as an axillary equipment
in a direction finding system". The text go's on to say that the set is
in widespread use with US Forces all over the world. Typically, DF sets
are not built in very large quantities. The current field DF set(or was
until a couple years ago), is the TRQ-30(I have two of them). The one
in my collection was retired from service with the 501st Military Intelligence,
and consist of R-1518/UR (20-150mc AM/FM/CW in two bands), R-1218/UR (.5-20mc
AM/USB/LSB). DF Loop Antennas AS-1523(.5-21mc), AS-1526(19-50mc), AS-1527(45-100mc),
AS-1528(95-157.5mc), AB-1110 Ant. Pedestal/Tripod, and PNH-7 recorder.
It is entirely possible that the R-1444 is, or can be, a direct replacement
for the R-1218. But I still contend that it's primary role is that of
a general-purpose receiver, and it's direction finding qualities are only
secondary. Dennis *********************************************** TRP-4,
MYSTERY JAPANESE GREEN RADIO; From Breck Smith Information follows on
Japanese radio that I am trying to obtain information on. TRP-4 made by
OKI Electric Co. Ltd, Tokyo Japan. The 10.5 inch x 5 in x 10 in chassis
has the words TYPE TRP-4 SSB- TRANSCEIVER in the upper left of the front
control panel above the first row of controls. Length measurements are
without the battery box which extends the length another 3 inches. On
the bottom is a placard with the same info but has a design #31085 and
what appears to be a date of 1963.1 and SN of S-3587. The unit is sort
of a strange green, the contols look like PRC-10 items, there are corner
posts that extend out from the corners to protect the unit just like the
PRC-10 , the unit has two standard audio connectors on the left side,
one above the other and accepts standard handsets(H-33 etc). There are
two rows of controls that are next to each audio connector and go across
the front panel. The first row has a PUSH ON button for keying, a large
volumn control, a stardard square meter(marked with the OKI symbol ) an
ANT TUNE, Knob and a large recepticle for a ROD ANT(again like a PRC-9).
The second row of controls next to the audio connector are a SYSTEM SWITCH
marked off,rec, Send-A1, RT and ANT TUNE, then there is a CLARIFIER knob
and a channel select know which selects 6 crystal controlled channels.
Below the rod antenna is a Aux antenna connector with a small nut to hold
the wire and a ground connector marked "E" The unit is functional and
runs off of 7.5 VDC with the chassis being at a positive potential(being
familiar with 1960's vintage japanese radios I checked this before the
smoke test!) The unit is solid state and has a high voltage switching
power supply in the battery box which is attached to the bottom of the
radio with 6 hasp fasteners over center fasteners. The power supply appears
to run best at 7.5 volts and as the voltage input is increased the interior
section starts to regulate at 7.5, maybe the unit is designed for 12 volts
but I was afraid to try any higher once I got the thing working. As you
drop below 7.5 all the low voltages drop so the regulator is set for 7.5.
High voltages measured were in the 200 volt range. On transmitt one bias
voltage is generated in the the -26 volt range. Inside the battery box/
power supply, it has the label of DC-DC converter and also has terminals
for the "hand crank generator". There is a large two wire military connector
on the side and I tried a cannon connector shell on the threads and it
fit. The battery box connects to the R/T unit with a bundle of blue wires,
all the same color. The battery box is sectional with one section for
a battery and other section contains the switching power supply(solid
state) and a relay. Alone the center of the box is a divider which contain
the plug, and four conecters with nuts , the center of which is red and
black. The unit was tested and operates from 2.8 up through 8 mcs and
is on LOWER SIDEBAND. The IF is 455 kcs. The channels appear to be frequency
sensitive, you can only operate 2.8 mcs on the lower channels and say
7.1 mcs on the upper channels. The final amplifier is a tube type 5A6
on which I have no information.. Current draw is 20 to 50 mills with signal
being received and on transmitt is approximate 2 amps. Inside the R/T
unit are two sections, receive and transmitt. The receive section has
a large 1 inch by 2.5 in filter labeled CM filter and has a DATE of 9-62
which confirms the previously mentioned date. The interior has not been
sprayed or painted with any sort of anti -moisture or fungus material.
The connector on the rear of the RT unit mates with the power supply cable
and the connecor has three rows of pins , looks very similiar to R-174
receiver(ANGRR-5) but is larger has more pins. The receiver is contructed
of three main boards one on top and the other is on the bottom, a small
audio board is mounted on the side. The boards are soldered/hardwired.
The RF section has two small air variables , and six trimmers for the
channels. The entire RF section is hard wired, no boards, there are 6
cystals and standard HC-25 ceramic sockets and have a retaining clamps
with a thumb screw. On the top of the retaining clamp for the crystals
is a label" 2NDOSC(X-TAL). There is a single RT relay mounted below the
airvariables and it is enclosed in clear plastic but is soldered in place,
no socket. The ANT TUNE control on the front appear to operate a large
slug that goes in and out of a three inch tube with wrapped turns to tune
the antenna. Next the the final tube which has a shield are two more trimmers
marked 5 and 6. Any info would be appreciated Breck K4CHE, Dover Delaware |
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