The PHILCO Phorum
41-220 Capacitor - Printable Version

+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Philco Radio Discussions (https://philcoradio.com/phorum/forumdisplay.php?fid=5)
+--- Forum: Philco Electronic Restoration (https://philcoradio.com/phorum/forumdisplay.php?fid=8)
+--- Thread: 41-220 Capacitor (/showthread.php?tid=5683)

Pages: 1 2

RE: 41-220 Capacitor - Arran - 01-17-2013

That whole marine beacon argument never made much sense to me, if it was a problem with Philco sets it would have been a problem with any other make and model, and not just AC/DC sets, but only Philco used these things. Obviously RCA, FADA, Stromberg Carlson, G.E, brand Z, and even Hallicrafters engineers didn't think it was much of a concern for either reason. I've always put them back in just to be faithful to the original design. By the way I have picked up a beacon around the middle of the AM broadcast band, around 1060 when I used to listen to a station around that frequency, you could faintly hear a tone repeating a code in the back ground. I'm pretty sure that it was an image, or harmonic, of a beacon from the long wave band.
Regards
Arran

RE: 41-220 Capacitor - Jim Dutridge - 01-18-2013

Something is wrong with the wiring of this radio. As found the shields of the 7C7,7C6, 7B7 were all connected to the chassis but I don't see any chassis connection in the schematic. They all connect back to the power switch. Also as found was the shield of the 7A8 going to one side of the .25UFD cap #9 which the schematic shows going to the shield of the 7C7. Shield of the 7A8 is not connected to anything else except this capacitor.

I was under the impression that ALL shields should connected together and go to chassis. Anyone else have a properly working model that they can take a look at and tell me how these shields are connected?

RE: 41-220 Capacitor - Jim Dutridge - 01-19-2013

Problem resolved. After going back over the wiring I was sure that the shield of the 7A8 had to go to the chassis and sure enough it was thru the cap/coil combo that I decided to leave out. I only replaced the capacitor but no connection thru the deleted coil to the chassis.

Also found that the 250 pfd mica cap #32 was not in its proper place. It was connected on the 35A5 tube between pins 6 and 7. Thats how I found it originally. Once I removed it I decided to check its value and it was 1/10 of what it should have been. Read 25 pfd even though the color code was red,green, brown. Not having a 250 cap I paralled 2 120pfd silver micas and placed it between pins 2 and 7 of the 7C6 and restarted the alignment.

Although the loudness of the tone was not that great using the AVC voltage to set the alignment worked out just fine. I now have a playing 40-220. Now all thats left is to replace the yellowed and partially shrunken dial lens.