Polytechnic Research PRD Type 277A Standing Wave Amplifier Operating Instruction

Polytechnic Research PRD Type 219 Standing Wave Indicator Operating Instructions

Polytechnic Research PRD Type 809 Klystron Power Supply Operating Instruction

Polytechnic Research PRD Type 250-A Broadband Probe Instruction & Part Breakdown

Polytechnic Research PRD Type 650-B Universal Power Bridge Instructions 1956

Polytechnic Type 277 Standing Wave Amplifier Operation & Maintenance Handbook

PRD Electronics Type 277-D SWR/Attenuation Meter Operating Instruction 1967

PRD Types 219, 219-H, 219-L Standing Wave Detectors Operating Instructions 1960