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Philco 70 Pot replacement
#1

Dear All,

I`m finishing the restoration of 3 Philcos 70 with the lower numbers chassis. For all of them, I rewound the primary of the oscillator coil, replaced all internal caps of the block and metal case condensers, re-stuffed the electrolytics, and replaced the tone control cap. For two of them the pots were still OK, and the radios are playing great after the alignment. However, for the third one, the original pot was bad and I bought a 5K 4W wirewound pot from ebay (they come from China) to replace the original. I put a 220 ohms 2W resistor between F and G (see schematics at http://www.nostalgiaair.org/PagesByModel...013833.pdf) and connected the RF cathode to F. The 5k pot connections I kept according to the original schematics. A former owner replaced the 250 ohms DC choke to a 150 ohms DC one. The new electrolytics are 10 µF.
It worked, but the sound is very low only at the end of the pot. Is there alternative connections that will get the radio back to the right track?

Thank you.
Kadulazarini


Messages In This Thread
Philco 70 Pot replacement - by kadulazarini - 10-27-2013, 01:43 PM
RE: Philco 70 Pot replacement - by morzh - 10-27-2013, 03:27 PM
RE: Philco 70 Pot replacement - by kadulazarini - 10-27-2013, 07:22 PM
RE: Philco 70 Pot replacement - by morzh - 10-29-2013, 04:07 PM



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