05-13-2026, 05:40 PM
Hello,
I am having a difficult time getting this radio finished. It plays very well but it has an intermittent problem where the reception drops off leaving a weaker signal.
What I have done to this radio is replaced all caps, ecaps, micas and resistors. The canned ohm is measuring good. I have run wires from grounding eyes to new ground points. I have cleaned ground straps on tuning condenser. I even took out the antenna coil looking for problems finding none but resoldered the contacts while I was there. When the signal drops out I can still detect the oscillator on another radio. The signal on a weaker station is gone but on a strong station it is there but much weaker. I have replaced the 6A8 tube with two others and the 6H6 and 6F5 with one other. When the signal is weak touching the 6A8 cap increases the signal.
Two problems I see is plate voltage on tubes is lower than listed by about 25 volts. Second is the AVC voltage does not vary much between no station and strong station while playing normally reading about -2.2 to -2.7 so very little change. I'm measuring on pin 8 of the 6H6 tube.
Using my signal tracer is no help as soon as I touch the RF probe to anything the signal returns to normal.
Any help would be greatly appreciated. I have previously posted on the ARF site. https://antiqueradios.com/forums/viewtop...ca8642a2ce
Dan
I am having a difficult time getting this radio finished. It plays very well but it has an intermittent problem where the reception drops off leaving a weaker signal.
What I have done to this radio is replaced all caps, ecaps, micas and resistors. The canned ohm is measuring good. I have run wires from grounding eyes to new ground points. I have cleaned ground straps on tuning condenser. I even took out the antenna coil looking for problems finding none but resoldered the contacts while I was there. When the signal drops out I can still detect the oscillator on another radio. The signal on a weaker station is gone but on a strong station it is there but much weaker. I have replaced the 6A8 tube with two others and the 6H6 and 6F5 with one other. When the signal is weak touching the 6A8 cap increases the signal.
Two problems I see is plate voltage on tubes is lower than listed by about 25 volts. Second is the AVC voltage does not vary much between no station and strong station while playing normally reading about -2.2 to -2.7 so very little change. I'm measuring on pin 8 of the 6H6 tube.
Using my signal tracer is no help as soon as I touch the RF probe to anything the signal returns to normal.
Any help would be greatly appreciated. I have previously posted on the ARF site. https://antiqueradios.com/forums/viewtop...ca8642a2ce
Dan




