Rear panel connector wiring - both models

Install a pair of 3501FP or equivalent RCA jacks in the two empty holes near the IF Output jacks, then wire the Sidetone Out (bottom) and Phone Patch In (top) connections. Use a few of the 1.8mm tie wraps to include the new Miniax runs in the existing cable bundles.

New Jacks.jpg

Note that the Sidetone Out line is at full oscillator volume. A pad may be added at the external receiver (or built into the patch cable itself) to set the level heard from the receiver's speaker.