03-09-2026, 03:39 PM
Re the hum, check the "lead dress". If the audio wires to the switch are long, use shielded cable. Ground one end of the cable to the chassis. Also, verify the correct wiring of the filter caps.
Re the Phantom voltages, what the others said is correct. The original Philco arrangement was to have the 2 power line bypass caps in series with the center junction connected to chassis. (If you have the chassis grounded to a water pipe (or even to the house wiring), the phantom voltage will be gone. An alternative to the original wiring for these RF Bypass caps is to place one cap across the power line (post power switch) the other cap from the leg without the switch to chassis ground, and to install a polarized plug so that the switch side is Hot and the unswitched side (with the cap to chassis is Neutral. This would eliminate the 60V (low current) on the chassis. However, the noise may either decrease or increase.
Re the Phantom voltages, what the others said is correct. The original Philco arrangement was to have the 2 power line bypass caps in series with the center junction connected to chassis. (If you have the chassis grounded to a water pipe (or even to the house wiring), the phantom voltage will be gone. An alternative to the original wiring for these RF Bypass caps is to place one cap across the power line (post power switch) the other cap from the leg without the switch to chassis ground, and to install a polarized plug so that the switch side is Hot and the unswitched side (with the cap to chassis is Neutral. This would eliminate the 60V (low current) on the chassis. However, the noise may either decrease or increase.
"Do Justly, love Mercy and walk humbly with your God"- Micah 6:8
"Let us begin to do good"- St. Francis
Best Regards,
MrFixr55




