Phase Linear 4000 Autocorrelation Preamplifier

It powers on and plays in stereo on right side but not left, in mono both sides play. If you plug the inputs into LR & RR you get sound out of stereo on both sides but not in regular L & R inputs. I know it sounds confusing but I am trying to explain all that happening.

Phase Linear 700, 700B, 700II DC Protect Board

Phase Linear 700, 700B, 700II DC Detect relay board. For added protection the relay “crowbars” (shorts across the speaker). Solder 2 AC wires to existing bridge rectifier. Attach supplied ground lug to DC capacitor copper bar.