[Milsurplus] SCR-A*-183/283 Data - Revised and Extended
Mike Morrow
kk5f at earthlink.net
Tue Aug 23 14:26:08 EDT 2011
The two postings that I made yesterday are now replaced completely with the
revised material that follows. Corrections and additions are most welcome.
--- System ---
Receiver, Transmitter, Junction Power MFR Contract
Coils Issued Coils Issued Box Unit Date
--------------------------------------------------------------------------------
---SCR-AA-183---
BC-AA-179 BC-AA-180 TM-AA-153 BD-AA-69 ARC 06-25-1932
? ?
---SCR-AB-183---
BC-AD-219 BC-AD-200 TM-AD-167 BD-AD-81 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 TM-AD-167 BD-AD-69 ARC 06-05-1935
? ?
---SCR-AE-183---
BC-AE-229 BC-AE-230 TM-AE-172 BD-AE-83 ARC 06-05-1935
? ?
---SCR-AF-183---
BC-AF-229 BC-AF-230 TM-AF-172 BD-AF-83 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-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 Electric
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 TM-AO-202 BD-AL-93 Graybar 06-20-1939
C-266 2500-4700 C-271 2500-3200 Electric
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 BD-AN-83 ? ?
? ?
---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 TM-AO-202 BD-AO-93 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-AP-183---
BC-AP-229 BC-AP-230 TM-AH-172 BD-AP-83 ? ?
? ?
---SCR-AQ-283---
BC-AQ-429 BC-AQ-430 TM-AO-202 BD-AQ-93 WE Co. ??-??-1942
C-396 2500-4700 C-401 2500-3200
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 TM-AO-202 BD-AR-93 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-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
This list has been revised to incorporate data from T.O. 08-40SCR-1 found at
Mike Hanz’s site http://aafradio.org/docs/SCR-183-283_interchangeability.pdf .
This document is “must have” for anyone studying these sets. It lists almost
every 183/283 component, although there’s not enough information to definitely
associate coil sets listed to the appropriate system.
There was a recent list discussion about the frequency coverage of the
SCR-A*-183/283 receivers. For most of these receivers there was a full set of
receiver coils that allowed coverage from 150 kHz up to 12500 kHz when used in
liaison service. AFAIK there were no command set receivers issued with coil
sets other than those for the limited ranges shown above. Dave Stinson’s
statement that SCR-A*-183 receiver coverage ended at 7700 kHz seems well founded.
Only if the receiver was part of a liaison set were full coils sets supplied.
For example, the 1935 SCR-AG-183 manual is also the manual for the receiving
equipment of the SCR-AC-187.
The SCR-AG-183 command set receiver BC-AG-229 was supplied with two dual-band
and two single-band coils sets:
C-153-A 201- 398, 2500-4700
C-155-A 201- 398, 4150-7700
C-171 2500-4700
C-172 4150-7850
The SCR-AC-187 liaison set receiver BC-AG-229 was supplied with eight single-band
coils sets:
C-166 150- 300
C-167 200- 400
C-168 400- 800
C-169 800- 1600
C-170 1600- 3000
C-171 2500- 4700
C-172 4150- 7850
C-173 7000-12500
Coil sets for a command set receiver require a calibrated dial for the MC-125
remote tuning unit. The BC-AG-229 in the SCR-AG-183 command set was supplied
with:
MC-144-A 201-398, 2500-4700
MC-145-A 201-398, 4150-7700
The BC-AG-229 in the SCR-AC-187 liaison set was provided with no such dials.
It was locally controlled, using its 0-100 dial and the MC-146-A tuning chart.
I suspect that there were instances where these receivers in command set service
were NOT remote tuned. These MCW-only broad bandpass TRF receivers would have
been usable when fix-tuned before flight, if no beacon-band reception using a
dual-band coil set was required.
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
The manual for SCR-AS-183 command set lists 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
It is unlikely that any BC-AS-229 ever served in liaison service, so most
of the full coil set likely never existed.
SCR-AS-183 command set was sometimes 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. There were NO receiver coils. None
was 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. After 15 years of seeking out BC-AS-229 receivers, I have
never found one with an -AS- coil set in place. They seem always to be -AR-
coil sets, usually the C-379. I have located only one -AS- coil set...a
C-437. The –AR- coil sets were completely interchangeable with the –AS-
equivalents, so perhaps there was sufficient supply of –AR- coil sets for
–AS- receiver service.
DEVELOPMENT: The USN's first GF command set (11/10/1932) consisted of the
GF CBY-46006 receiver and the GF CBY-52004 transmitter. I call this the
GF/GF set to indicate that both the receiver and the transmitter bear the
GF designation. The GF receiver has four RF amplifiers (39/44), detector
(36), and AF amplifier (38). It has no CW heterodyne oscillator or AGC.
I haven’t seen indication that this GF receiver bore duplicate designation
as the RU-1, but it’s possible. According to SHIPS 242, the 1931 RU-1
covered 250 to 14000 kHz. Someone with documentation that the RU-1 is also
a CBY-46006 could answer that question. The GF CBY-52004 transmitter has
a master oscillator (10), power amplifier (10), plate modulator (45 Spl),
and AF/MCW oscillator (10).
At some point, the GF CBY-46006 receiver in the GF/GF set was replaced by the
RU-2 CBY-46012 receiver. That unit reduces the RF amplifiers to three, adds
a CW heterodyne oscillator (36) in the space freed up, and still has no AGC.
The RU-2 with its CW capability was intended for general liaison set service
and now served in the RU-2/GF command set. It uses 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 of command sets using the GF
CBY-52004 transmitter.
The next USN command set in this series is the RU-3/GF-1 (02/10/1934). The
RU-3 CBY-46036 receiver adds an AGC stage (77) by combining the CW oscillator
and AF functions in a dual triode (38233) and changing the RF amplifier (78)
and detector (77) tubes. All future RU-series receivers differ little from
the RU-3 other than the location of the AGC bias resistor (in the dynamotor
unit for the command set CBY-46051 versions and in the receiver unit for the
liaison set CBY-46048 versions) or the maximum capacity of the ganged tuning
condensers (made larger in the RU-8 and RU-9 CBY-46064 to increase coverage
of the coil sets). The GF-1 CBY-52027 transmitter design remained similar
to the CBY-52004 with a master oscillator (10), power amplifier (10), plate
modulator (45 Spl), and AF/MCW oscillator (10). Transmitters after the GF-1
were radically redesigned as a master oscillator (89), push-pull power
amplifier (2x837), and power amplifier grid modulator (89).
This discussion of the RU/GF sets serves to compare to SCR-A*-183/283
series development.
The receiver design of the USAAC sets appears to be very close in staging
to the CBY-46006 receiver. The 1934 BC-AB-199 receiver has four RF
amplifiers (39/44), detector (37), and AF amplifier (38), with simple AGC
developed from the detector stage. The only obvious change that took place
in subsequent receiver development was altering the loop connections from
terminal posts, to connector plugs, to total elimination of loop functions.
The 1934 BC-AB-200 transmitter is identical to the USN's 1934 GF-1
transmitter except for connector. After the BC-AB-200, transmitter design
was changed to replace the plate modulator (45 Spl) and AF/MCW oscillator
(10) with two parallel plate modulator (45 Spl) tubes. RF coils were also
redesigned. Transmitter design was essentially unchanged afterwards.
It's notable that the SCR-AA-183 contract date is 06-25-1932. The GF/GF
contract date is 11-10-1932, five months later. USAAC SCR-A*-183 set
receiver and transmitter design stabilized in early 1934 status, while
significant improvements were made in USN RU/GF set receiver and transmitter
design before stabilizing for later versions in late 1934 status.
Mike / KK5F
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