This 82 pound RBC-1 has a September 1941 contract date. It was built by RCA for the Navy. It covers 4 to 27 MHz in 4 bands.
The RBB is a very similar superhet companion radio covering 500 KHz to 4 MHz. The combination usually includes the RBA which is a TRF set covering the VLF spectrum below 600 KHz. All were designed to be stable on a battleship firing heavy guns.
The RBC-1 is a single conversion 19 tube set, with a separate power supply. This set did not come with the supply, so I modified a small dispatch consolette purchased for parts to be the power supply and to use its speaker. The set is a superb performer with excellent shielding and an uncompromising quality late 1930s design. It has exceptional sensitivity with just a short piece of wire for an antenna. The left side is the RF section and the right is the IF and audio section. The two sections can readily be separated for service. According to the internal nomenclature plate, the audio/ IF section is the same for both the RBB and RBC. The 400 KHz IFs are electrically designed to provide three switchable levels of selectivity. Further selectivity is provided through excellent audio filters. The RF oscillator's B+ is voltage regulated and its filament is stabilized through use of a ballast tube. Note the separate meter for monitoring the main 200 volt B+.
According to Robert Login's (AA8A) on-line article on the receiver series from the October 1998 issue of Electric Radio (link is to the ER index), the RBC-1 cost the Navy $2400 in 1940. Login quotes Jack Strayer in ER May 1993 noting that RCA "borrowed" the top engineers from 17 companies to design the radio series resulting in what Strayer noted as a radio that is a "design engineer's dream come true."
I was able to build a power supply based upon the voltage/ current information on this nomenclature tag.
Note the RF section on the left and IF/AF section on the right.
The University of Texas at Austin amateur radio club station
has a nice RBC-5 built under a later (1952?) contract. Its color is the later Navy gray paint.