TM 11-4057.pdf  Repair Instructions, Radio Transmitters BC-610-A, -B, -C, -D and -E.  December 1945.
TM 11-826.pdf  Manual for Radio Transmitters BC-610-E, -F, -G, -H, -I and Radio Transmitter T-213/GRC-26 and Antenna Tuning Units BC-939-A and -B.  1952.

These files are made available with the compliments of August Johnson, KG7BZ.