For sale is reprint of TMC GPR-90 Communications Receiver manual. Manual is 42 pages including 11×28″ Circuit Diagram foldout.
Includes change #1 dated 12/26/1962. Sections on Installation, Operation, Alignment, Service and Test data. Comes with Voltage/Resistance tables for all tube sockets, helpful when troubleshooting. Must for every owner of this rare receiver.