HELP!! What is this? - Printable Version
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+- The PHILCO Phorum (https://philcoradio.com/phorum)
+-- Forum: Various and Sundry Categories (https://philcoradio.com/phorum/forumdisplay.php?fid=37)
+--- Forum: Other Radios (Non-Philco) (https://philcoradio.com/phorum/forumdisplay.php?fid=12)
+--- Thread: HELP!! What is this? (/showthread.php?tid=6358)
HELP!! What is this? - Eric Adams - 03-31-2013
Just when I'm begining to think I know what I'm doing I get a new project to remind me that I don't!
Can someone please tell me what this is? I think it is a capacitor of some kind.
Thanks,
Eric
RE: HELP!! What is this? - morzh - 03-31-2013
Eric
Which one is it? The cylindrical thingy at the bottom with the green/white/three red stripes?
Strange marking for a cap, could be a resistor, but: do you know what radio you are dealing with and do you have its schematic? That would take the guesswork out.
RE: HELP!! What is this? - Eric Adams - 03-31-2013
Hi Morzh,
Yes, that is the one I'm talking about. It goes from pin 6 of one of the 12AU6s to ground. From looking at the schematic it shows a .003 cap. I tested it and my capacitor tester isn't even close to that value.
Eric
Here's the schematic: http://www.nostalgiaair.org/Resources/312/M0025312.htm
RE: HELP!! What is this? - morzh - 03-31-2013
Actually it shows 0.01uF cap, but still does not fit the marking.
RE: HELP!! What is this? - Eric Adams - 04-01-2013
What does the marking say? Is it a cap?
RE: HELP!! What is this? - morzh - 04-01-2013
Not sure....red is 2, white is 9, green is 5.
RE: HELP!! What is this? - Eric Adams - 04-01-2013
Are the color codes the same for resistors and caps? Is this a cap?
RE: HELP!! What is this? - Mondial - 04-01-2013
The cap connected to pin 6 of the 12AU6 ( 12BA6?) looks like it is C13, a screen bypass cap. It appears from the color code to be 2200 pF, (.0022 uF), which puts it pretty close to the .002 uF I read on the schematic for C13.
What did you measure the mystery cap's value to be? It definitely looks like an early molded paper cap, with the resistor color code used for indicating value.
Edit: I looked at the photo again and it looks like the mystery cap is connected to pin 6 of the 12BA6 first IF tube. It appears that the second IF 12BA6 also uses the same .002 uF screen bypass. The 12AU6 tube should be the limiter, connected to the discriminator transformer near the 19T8.