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Philco 21 repair
#10

Quote:I'm going to change that,and wire it per schematic unless somebody tells me different.
That is fine but stick close to the values in the schematic. The filter is tuned to reduce hum rather than brute force.

IMNSHO Don't bother to stuff the Mershons. Install a tie strip under chassis to deal with all the leads and install axials or radials. That way if the hum is objectionable changing the value of filter cap after the choke will have a better effect. If the first filter cap after the rectifier is too high stressful for the rectifier and will raise the B+ which, because of higher line voltage will be higher too. Put the Mershons back in the chassis for show...

You may have to tinker with the back bias resistor for the 45's so they run just warm...

You did notice that inside one of the Bakelite blocks is a crude wire-wound resistor Icon_biggrin

Were the RF/IF coils all measured for continuity?

GL

Chas

Pliny the younger
“nihil novum nihil varium nihil quod non semel spectasse sufficiat”


Messages In This Thread
Philco 21 repair - by Simon Wa3uay - 06-19-2019, 04:28 PM
RE: Philco 21 repair - by Simon Wa3uay - 06-19-2019, 04:31 PM
RE: Philco 21 repair - by Chas - 06-19-2019, 09:17 PM
RE: Philco 21 repair - by Radioroslyn - 06-20-2019, 10:22 AM
RE: Philco 21 repair - by Steve Davis - 06-20-2019, 11:38 AM
RE: Philco 21 repair - by Radioroslyn - 06-20-2019, 11:50 AM
RE: Philco 21 repair - by Simon Wa3uay - 06-21-2019, 09:44 AM
RE: Philco 21 repair - by Simon Wa3uay - 06-24-2019, 09:19 AM
RE: Philco 21 repair - by Simon Wa3uay - 07-22-2019, 04:12 PM
RE: Philco 21 repair - by Chas - 07-22-2019, 07:06 PM
RE: Philco 21 repair - by Radioroslyn - 07-22-2019, 08:07 PM
RE: Philco 21 repair - by Chas - 07-22-2019, 11:41 PM
RE: Philco 21 repair - by Simon Wa3uay - 07-23-2019, 11:26 AM
RE: Philco 21 repair - by Simon Wa3uay - 09-10-2019, 04:06 PM
RE: Philco 21 repair - by bensharp27 - 09-10-2019, 08:43 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-11-2019, 10:39 AM
RE: Philco 21 repair - by morzh - 09-11-2019, 12:32 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-11-2019, 01:02 PM
RE: Philco 21 repair - by rfeenstra - 09-11-2019, 01:53 PM
RE: Philco 21 repair - by morzh - 09-11-2019, 02:09 PM
RE: Philco 21 repair - by Steve Davis - 09-11-2019, 10:08 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-12-2019, 01:31 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-19-2019, 09:54 AM
RE: Philco 21 repair - by morzh - 09-19-2019, 11:32 AM
RE: Philco 21 repair - by Simon Wa3uay - 09-19-2019, 12:46 PM
RE: Philco 21 repair - by Steve Davis - 09-19-2019, 01:11 PM
RE: Philco 21 repair - by rfeenstra - 09-19-2019, 01:42 PM
RE: Philco 21 repair - by morzh - 09-19-2019, 01:52 PM
RE: Philco 21 repair - by Radioroslyn - 09-19-2019, 05:09 PM
RE: Philco 21 repair - by rfeenstra - 09-19-2019, 05:47 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-20-2019, 08:44 AM
RE: Philco 21 repair - by morzh - 09-20-2019, 01:17 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-23-2019, 11:39 AM
RE: Philco 21 repair - by Radioroslyn - 09-23-2019, 12:07 PM
RE: Philco 21 repair - by Simon Wa3uay - 09-25-2019, 07:58 PM
RE: Philco 21 repair - by Simon Wa3uay - 10-10-2019, 11:36 AM
RE: Philco 21 repair - by morzh - 10-10-2019, 12:10 PM
RE: Philco 21 repair - by Simon Wa3uay - 10-10-2019, 07:05 PM
RE: Philco 21 repair - by morzh - 10-11-2019, 09:07 AM



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