01-07-2010, 08:00 AM
Hi Harlan
Question: Why did you replace the volume and tone controls? Did you try cleaning them first? Just curious.
I have noticed this same phenomenon in some Philcos with this tone control circuit. The first thing I suggest is that you recheck your wiring. A miswired volume and/or tone control will cause the symptoms you describe. I've had it happen to me before.
Regarding the howl/squealing, recheck your alignment. Check components around the mixer, oscillator and IF circuits. Are the resistors within 20% tolerance? How about those mica caps? Could be leaky?
And on that loop antenna. No, it isn't easy to move, is it? Personally, I reach around in back to move the loop when needed. I think Philco intended for the set owners to find a good spot for average reception and leave the loop there. Of course, they did have that accessory add-on to add an external antenna if needed. I have one of those around here somewhere...it has been temporarily lost in my recent move...I've had some requests to draw a schematic for it, I'll try to honor those requests if I ever find the thing again.
Question: Why did you replace the volume and tone controls? Did you try cleaning them first? Just curious.
I have noticed this same phenomenon in some Philcos with this tone control circuit. The first thing I suggest is that you recheck your wiring. A miswired volume and/or tone control will cause the symptoms you describe. I've had it happen to me before.
Regarding the howl/squealing, recheck your alignment. Check components around the mixer, oscillator and IF circuits. Are the resistors within 20% tolerance? How about those mica caps? Could be leaky?
And on that loop antenna. No, it isn't easy to move, is it? Personally, I reach around in back to move the loop when needed. I think Philco intended for the set owners to find a good spot for average reception and leave the loop there. Of course, they did have that accessory add-on to add an external antenna if needed. I have one of those around here somewhere...it has been temporarily lost in my recent move...I've had some requests to draw a schematic for it, I'll try to honor those requests if I ever find the thing again.
--
Ron Ramirez
Ferdinand IN
