[Milsurplus] SCR-A*-183/283 Data From My Manuals and Other Sources
Mike Morrow
kk5f at earthlink.net
Mon Aug 22 17:31:17 EDT 2011
The SCR-A*-183/283 sets are a bewildering collection of similar components
bearing many different nomenclatures (especially the coil set numbers).
Even the USN's cosmetically similar and numerous RU/GF series seems easier
to catalog system detail.
Below is some compiled data (unfortunately incomplete) for the SCR-A*-183/283
systems. Most of the data comes direct from manuals I've collected. Every
set variation that I've been able to find documented somewhere is listed, even
if I have little data on the set.
There are several list members who have done far more research and are much
more knowledgeable than I am on this subject, but I thought it may be helpful
to illustrate the principal features of the development of this command set
until others who are better prepared publish more. I welcome correction,
addition, and comment.
--- System ---
Receiver Transmitter Junction Power MFR Contract
Coils Issued Coils Issued Box Unit Date
--------------------------------------------------------------------------------
---SCR-AA-183---
BC-AA-179 BC-AA-180 ? ? ARC 06-25-1932
? ?
---SCR-AB-183---
BC-AD-219 BC-AD-200 ? ? ARC 04-19-1934
? ?
---SCR-AC-183---
BC-AB-199 BC-AB-200 TM-AB-167 BD-AB-69 ARC 03-15-1934
C-127 224- 448 C-140 6200-7700
C-128 400- 800 C-141 3050-3800
C-129 800-1600 NOTES:
C-130 1600-3000 Receiver stages: 4 RF, Detector, AF
C-131 2500-4700 Receiver has loop antenna posts.
C-132 4150-7850 Transmitter stages: MO, PA, Plate Mod, AF Osc.
---SCR-AD-183---
BC-AD-199 BC-AD-200 ? ? ARC 06-05-1935
? ?
---SCR-AE-183---
BC-AE-229 BC-AE-230 ? ? ARC 06-05-1935
? ?
---SCR-AF-183---
BC-A?-229 BC-A?-230 TM-AF-172 ? ARC ?
? ?
---SCR-AG-183---
BC-AG-229 BC-AG-230 TM-AE-172 BD-AG-83 ARC 11-25-1935
C-153-A 201- 398 C-216 2500-3200
2500-4700 C-217 3200-4000
C-155-A 201- 398 C-218 4000-5000 Notes:
4150-7700 C-219 5000-6200 Receiver stages: 4 RF, Detector, AF
C-171 2500-4700 C-220 6200-7700 Receiver has loop antenna connector plug.
C-172 4150-7850 Transmitter stages: MO, PA, Plate Modulators
---SCR-AH-183---
BC-AH-229 BC-AH-230 TM-AH-172 BD-AG-83 ARC 11-25-1935
C-153-A 201- 398 C-216 2500-3200
2500-4700 C-217 3200-4000
C-155-A 201- 398 C-218 4000-5000 Notes:
4150-7700 C-219 5000-6200 Receiver stages: 4 RF, Detector, AF
C-171 2500-4700 C-220 6200-7700 Receiver has loop antenna connector plug.
C-172 4150-7850 Transmitter stages: MO, PA, Plate Modulators
---SCR-AI-183---
BC-A?-229 BC-A?-230 ? ? ARC ?
? ?
---SCR-AJ-183---
BC-AH-229 BC-AH-230 TM-AH-172 BD-AG-83 ARC 08-14-1937
C-153-A 201- 398 C-216 2500-3200
2500-4700 C-217 3200-4000
C-155-A 201- 398 C-218 4000-5000 Notes:
4150-7700 C-219 5000-6200 Receiver stages: 4 RF, Detector, AF
C-171 2500-4700 C-220 6200-7700 Receiver has loop antenna connector plug.
C-172 4150-7850 Transmitter stages: MO, PA, Plate Modulators
---SCR-AK-183---
BC-AH-229 BC-AH-230 TM-AH-172 BD-AK-83 ARC 01-10-1939
C-155-A 201- 398 C-216 2500-3200
4150-7700 C-217 3200-4000 Notes:
C-171 2500-4700 C-218 4000-5000 Receiver stages: 4 RF, Detector, AF
C-219 5000-6200 Receiver has loop antenna connector plug.
C-220 6200-7700 Transmitter stages: MO, PA, Plate Modulators
---SCR-AL-183---
BC-AL-229 BC-AL-230 TM-AH-172 BD-AL-83 Graybar 06-20-1939
C-266 2500-4700 C-271 2500-3200
C-270 201- 398 C-272 3200-4000 Notes:
4150-7700 C-273 4000-5000 Receiver stages: 4 RF, Detector, AF
C-274 5000-6200 Receiver has loop antenna connector plug.
C-275 6200-7700 Transmitter stages: MO, PA, Plate Modulators
---SCR-AL-283---
BC-AL-429 BC-AL-430 Part of BD-AL-93 Graybar 06-20-1939
C-266 2500-4700 C-271 2500-3200 Aircraft
C-270 201- 398 C-272 3200-4000 Notes:
4150-7700 C-273 4000-5000 Receiver stages: 4 RF, Detector, AF
C-274 5000-6200 Receiver has loop antenna connector plug.
C-275 6200-7700 Transmitter stages: MO, PA, Plate Modulators
---SCR-AN-183---
BC-AN-229 BC-AN-230 TM-AH-172 ? ? ?
? ?
---SCR-AO-183---
BC-AO-229 BC-AO-230 TM-AH-172 BD-AO-83 WE Co. 06-18-1941
C-346 2500-4700 C-351 2500-3200
C-350 201- 398 C-352 3200-4000 Notes:
4150-7700 C-353 4000-5000 Receiver stages: 4 RF, Detector, AF
C-354 5000-6200 Receiver has loop antenna connector plug.
C-355 6200-7700 Transmitter stages: MO, PA, Plate Modulators
---SCR-AO-283---
BC-AO-429 BC-AO-430 Part of BD-AO-93 WE Co. 06-18-1941
C-346 2500-4700 C-351 2500-3200 Aircraft
C-350 201- 398 C-352 3200-4000 Notes:
4150-7700 C-353 4000-5000 Receiver stages: 4 RF, Detector, AF
C-354 5000-6200 Receiver has loop antenna connector plug.
C-355 6200-7700 Transmitter stages: MO, PA, Plate Modulators
---SCR-AP-183---
BC-AP-229 BC-AP-230 TM-AH-172 ? ? ?
? ?
---SCR-AQ-283---
BC-AQ-429 BC-AQ-430 Part of BD-AQ-93 WE Co. ??-??-1942
C-396 2500-4700 C-401 2500-3200 Aircraft
C-400 201- 398 C-402 3200-4000
4150-7700 C-403 4000-5000 Receiver stages: 4 RF, Detector, AF
C-404 5000-6200 Receiver has NO loop antenna connection.
C-405 6200-7700 Transmitter stages: MO, PA, Plate Modulators
---SCR-AR-183---
BC-AR-229 BC-AR-230 TM-AH-172 BD-AR-83 WE Co. ??-??-1942
C-376 2500-4700 C-381 2500-3200
C-377 4150-7700 C-382 3200-4000 Notes:
C-379 201- 398 C-383 4000-5000 Receiver stages: 4 RF, Detector, AF
2500-4700 C-384 5000-6200 Receiver has NO loop antenna connection.
C-380 201- 398 C-385 6200-7700 Transmitter stages: MO, PA, Plate Modulators
4150-7700
---SCR-AR-283---
BC-AR-429 BC-AR-430 Part of BD-AR-93 WE Co. ??-??-1942
C-376 2500-4700 C-381 2500-3200 Aircraft
C-377 4150-7700 C-382 3200-4000 Notes:
C-379 201- 398 C-383 4000-5000 Receiver stages: 4 RF, Detector, AF
2500-4700 C-384 5000-6200 Receiver has NO loop antenna connection.
C-380 201- 398 C-385 6200-7700 Transmitter stages: MO, PA, Plate Modulators
4150-7700
---SCR-AS-183---
BC-AS-229 BC-AS-230 TM-AH-172 BD-AS-83 Philco 04-03-1943
C-436 2500-4700 C-431 2500-3200
C-437 4150-7700 C-432 3200-4000 Notes:
C-439 201- 398 C-433 4000-5000 Receiver stages: 4 RF, Detector, AF
2500-4700 C-434 5000-6200 Receiver has NO loop antenna connection.
C-440 201- 398 C-435 6200-7700 Transmitter stages: MO, PA, Plate Modulators
4150-7700
I don't have any positive evidence that a SCR-AS-283 existed.
There was a recent discussion about the frequency coverage of the receivers
in this series. For most of these sets there was **theoretically** a full
set of receiver coils that could allow coverage from 150 kHz up to 12500 kHz,
but AFAIK there were NO ACTUAL receivers issued with coils sets other than
those for the limited ranges shown above. The most accurate statement does
seem indeed to be the one that Dave made about receiver coverage ending at
7700 kHz.
For example, the 1935 SCR-AG-183 system picture in its manual shows eight
single-band receiver coil sets C-161 though C-173 to provide 150 to 12500 kHz
coverage, plus two dual-band coils set C-153A and C-155-A. However, the manual
states that only the four coils sets shown in my table above (C-153-A, C-155-A,
C-171, C-172) were provided as part of the SCR-AG-183. I have seen no documentation
that indicates that coils sets were supplied for frequencies above 7700 kHz in
*any* SCR-A*-183/283 set. A supplied receiver coil set would likely have been
accompanied by an appropriately-calibrated MC-xxx dial for the MC-125 remote
tuning unit. I suspect that there were instances where the receiver was NOT remote
tuned. A broad bandpass TRF receiver like this should have been usable fix-tuned
before flight, if no beacon-band reception using a dual-band coil set was
anticipated.
The last of this series, the SCR-AS-183, illustrates an extreme example of
limited receiver coil set supply. The MC-401 data plate on the receiver tube
cover (found on most but not all BC-AS-229 receivers) shows data for the
following coils sets:
C-436 2390- 4880
C-437 4040- 7880
C-438 6480-12700
C-439 200- 400, 2470- 4830
C-440 200- 400, 4100- 7730
C-441 146- 304
C-442 193- 405
C-443 390- 815
C-444 780- 1635
C-445 1535- 3160
On the other hand, the manual for SCR-AS-183 list ONLY four coil sets as part
of the contract supplying the set, with nominal ranges:
C-436 2500- 4700
C-437 4150- 7700
C-439 201- 398, 2500- 4830
C-440 201- 398, 4150- 7700
In reality, the SCR-AR-183 was apparently often supplied with NO receiver coils.
I obtained an unopened since manufacture wooden crate containing an SCR-AS-183.
There was a full set of transmitting coils, stamped in paint with the transmitter's
serial number. But...there were NO receiver coils, not even the four listed in the
manual. Nor were they listed on the mimeographed packing list form as an option for
inclusion, nor was there apparently an additional crate that would have contained
the missing coils. In almost 15 years of seeking out BC-AS-229 receivers, I have
NEVER found one of these common variants with an -AS- coil set in place...they were
always -AR- coil sets (C-379). I have located only one real -AS- coil set...the C-437,
and it was still in original packaging.
The USN's first GF command set (11/10/1932) consisted of the GF receiver (CBY-46006)
and the GF transmitter (CBY-52004). I call this the GF/GF set, to indicate that both
the receiver and the transmitter bore the GF designation. This GF receiver had no
CW heterodyne oscillator and no AGC. I have never seen anything that indicates that
this GF receiver bore any duplicate designation as the RU-1. According to SHIPS 242,
the RU-1 covered 250 to 14000 kHz and dated from 1931.
At some point, the GF receiver in the GF/GF set was replaced by the RU-2 (CBY-46012)
receiver, which incorporated a CW heterodyne oscillator, but still no AGC. The RU-2
was also intended for liaison set service, but now it was part of the RU-2/GF set.
It used the same junction box (CBY-23011) and power supply (CBY-21105) as the GF/GF
set. The GF/GF and the RU-2/GF represent two distinct variations.
The next USN command set in this series was the RU-3/GF-1 (02/10/1934). The RU-3
receiver (CBY-46036) now had a CW heterodyne oscillator and AGC. All future RU-series
receivers (up to 1941 RU-18) differed little from the RU-3. The GF-1 transmitter
(CBY-52027) was still a MO (10), PA (10), Plate Modulator (45 Spl), AF Oscillator (10)
design that differed qreatly from all the post-GF-1 transmitters which were configured
as a MO (89), P-P PA (2x837), PA grid modulator (89).
I diverted into this discussion of the early sets RU/GF sets in order to comment on
the SCR-A*-183/283 series. The receivers of ALL these USAAC/F sets are essentially
identical (except for connector) to the USN's original 1932 GF (CBY-46006) receiver,
which uses four RF stages and has neither CW heterodyne oscillator nor AGC. Similarly,
the USAAC/F transmitters are almost identical to the USN's 1934 GF-1 transmitter,
except that the simple design was improved *after* the SCR-AC-183 to replace the
separate Plate Modulator(10)/AF Oscillator(45 Spl) with two parallel Plate Modulator
(45 Spl) tubes, in addition to some redesign of the RF coils.
It's notable that the first SCR-AA-183 contract was 06-25-1932, which pre-dates the
first GF/GF which was 11/10/1932.
One would have thought it would have been cheaper and better for all parties to have
standardized on the basic design of the USN's 1934 RU-3a/GF-2. The different parts
logistics must have been taxing just by itself. I think A.R.C. made no SCR-A*-183
sets after the SCR-AK-183 of 01-10-1939, and I don't believe A.R.C made any SCR-A*-283
sets.
Free use of any of the above info is granted. Corrections, additions, and comments
(even opinions) are most welcome!
Mike / KK5F
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