Test sets 1-61-A, 1-61-B and 1-61-C - USA Voorschrift, Technical Manual, 11-346 Barographs ML-3-A, ML-3-B, ML-3-C, ML-3-D - USA Voorschrift, Technical Manual, 11-425 Amplifiers BC-1388, BC-1388-A, BC-1388-B, BC-1388-C, and frequency amplifier AM-844/U - USA Voorschrift, Technical Manual, 11-2556
