RCA-built CRV-46156, the first of the line was contracted for in 1935.  Though largely replaced by the later RBA, RBB, and RBC receivers, the RAL and its LF mate the RAK were still put to use on many vessels during WWII.  They were used extensively on submarines.  MASSACHUSETTS has a RAK/RAL pair in Radio Central and another pair in Radio III.  Most of the other LF/MF/HF receivers are the RBA, RBB, and RBCs.

 

The RAL covers 300Kc to 23Mc.  It has 2 RF stages and a regenerative detector.  I find it to be plenty sensitive, at least on 7Mc where I have used it most, but it is lacking in selectivity.  The lack of RF selectivity is somewhat compensated for by a narrow audio filter.  The RAL is quite stable, and I have been able to make contacts on single sideband on 14Mc using it.

 

This RBA-1, CFT-46154 was built by Federal Telegraph in Newark, NJ and covers 15-600Kc. It is a Tuned Radio Frequency (TRF) design with a heterodyne oscillator for CW reception.

 

The calibration chart lists the following stations:

NSS F 18.6kc (Arlington)

NAA F 15.5kc

NSS B 122kc

NBA F 32.6  (Panama)

NBL 450kc

GYU, GYW (Gibralter)

This list of stations suggests that this receiver was installed on a ship serving in the Atlantic.

 

RCA-made CRV-46147 receiver, covering .5 to 4Mc.  CRV indicates RCA manufacture.  46xxx indicates a receiver.  You will see this pattern in the rest of the gear.  Weighing in at 82 pounds, this is a really rugged and high-performance receiver.  This receiver and its brother the RBC were conceived and brought to manufacture in a rapid fashion right before the war, when the Navy realized that the RAK/RAL were not up to par.  MASSACHUSETTS carried RBC serial numbers 4 and 6, and RBB number 5.

 

RBB and RBC are single-conversion superhets with 400kc IF frequency.  The narrow bandwidth position is 1kc wide.  For AM or MCW use, an AVC function is available.  CW signals are held at a constant output using an output limiter.

 

CRV-46148 covering 4.0 to 27Mc. 

 

Shown above are: CAY-46077-A RBM-5 High Frequency Receiver

                            CAY-46076-A RBM-5 Medium Frequency Receiver

                            CAY-20086 Rectifier Power Unit.

 

CAY indicates Westinghouse manufacture.

 

These semi-portable receivers were designed for advanced base operations along with the TBW transmitter.  They could also be powered by a dynamotor supply. 

 

 A closely-related receiver is the RBS, electrically identical to the RBM HF unit, which was used for monitoring(bridge of Battleship) and backup purposes on ships. The Lionfish carries two RBS receivers.  RBS is designed to mount on a table.  The RBM has a waterproof carrying case that is set up as a portable operating position with legs and using the case lid as a desk.  Both the MF and HF receiver fit in one case, the same size as the ones the TBW units travel in. 

 

The LM frequency meter pictured on top of the Rectifier Power Unit is used to calibrate the RBM and TBW.

 

 

 

The RBK-1 was equipped with an IF output for an RBW panoramic adaptor, which displayed a 1 Megacycle wide spectrum for quickly finding signals.  The RBK/RBW combination was found in the Combat Information Center on many combat vessels.

 

The TBS is a transmitter-receiver pair that operates from 60 to 80Mc AM.  The receiver is a superhet with an IF of 5.3Mc.  The transmitter puts out 50W from an 808 modulated by a pair of 808s.

 

The TBS, originally contracted for in 1938, uses a mixture of big-pin and octal tubes.  It operates on one crystal-controlled channel.  It greatly simplified tactical communications in a convoy, especially when visibility made flag or blinking light communications difficult.  Those methods were slow even under the best of conditions.  While TBS is not officially an acronym for "Talk Between Ships", that describes its function well.