removed cap, lost radio on my 41-608
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Hello all, I sure hope I can get some help. While restoring my new Philco 41-608 i was cleaning the pots I noticed that there was a crackle and volume change whenever I touched a .002 MFD wax cap connected to the volume pot. I am a complete noobie when it comes to vintage electronic repair but I am familiar with guitars and their tone circuits. Decided to remove the capacitor that was causing the vol/crack issue. Wired it back with straight wire. Thing sounds amazing now! But the radio which worked fine now doesn't even try to work. My question is did my radio function Dependant on that missing cap? I also replaced the power wire out to the wall socket. Contact cleaner cleansed everything. The phono works. The iPod jack I wired to the phono preamp works and everything sounds great! The antenna is connected but nothing on the radio side works. Any help will help!
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http://www.nostalgiaair.org/PagesByModel...013433.pdf
Is this the sch?
What is the cap's position number? Is it #56?
Does your "wired with straight wire" mean you shorted the wire across where the cap was before?
If yes,
PS. It benefits everybody not to touch and mod circuitry one does not uderstand how it works. First understand it, then try to fix it.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
(This post was last modified: 03-01-2015, 09:48 PM by morzh.)
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(03-01-2015, 09:45 PM)morzh Wrote: What is the cap's position number? Is it #56?
YES its that one into the resistor. Kept the resistor
Quote:Does your "wired with straight wire" mean you shorted the wire across where the cap was before?
YES! Thats what I did.
Quote:It benefits everybody not to touch and mod circuitry one does not uderstand how it works. First understand it, then try to fix it.
Good advice, I didn't know what I don't know. Thought i understood the circuit. Thought won't
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Well...funny thing, shorting this cap should not kill rection, it is same as moving tone control pot to the High-most position.
Try to see if when you actually move it to that position the reception restores.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Welcome to the Phorum!! If you are interested in vintage radio restoration, take some time to read first. Here's a start but there is lots of info in this Phorum, the associated PhilcoRadio.com site and on the web. A place to find parts is here http://www.philcoradio.com/resourceb.htm . If the radio has not had the wax and electrolytic caps replaced, it would be good to do so as they will likely fail with continued use. As to the radio working before you jumped the #56 cap but not after, you could replace the cap with a new one and see if the radio recovers but I'd replace all the caps and at least check the resistors and replace those that are > 20% high. If it doesn't recover....others will be better at troubleshooting the radio than me.
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Trying that I can hear it trying to tune stations... Ordered sone replacement caps. You think my function selector switch being bad would cause my reception issue?
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You need to do a full recap first.
Here's the scenario: your shorted to GND path across the removed cap would behave as high tone position but then when you have the pot in the low tone position, should your #65 leak, you will lose the sound or major part of it.
Recap is the start of just about every restoration. Do it first.
Many problems will disappear before you will do something that they can manifest.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Wow thanks to both of you. I'm in love with this radio console. Will preform a full recap, test all resistors. No the caps I bought are 600v .002 MFD. As long as the voltage rating is as high or higher I should be OK right?
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Generally, yes.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Are these the ones you took out?
Or?
If these are new old stock you bought, do not use them.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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+1 on what morzh said. Old paper and wax caps, even though unused, are not reliable. You can get new caps easily enough from the resource list I mentioned before http://www.philcoradio.com/resourceb.htm#n . morzh usually buys from Mouser. I buy from Radio Daze and Antique Electronic Supply.
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And if you want them to look right, buy the tube axial types and stuff them inide the old ones, you can reserve the old wires and use them.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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Agree, the caps in the picturre you posted are about 50 years old!
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...and even if built yesterday, paper caps, now that we know of their problems, should be avoided altogether. Not that I know of any built yesterday...I think they no longer make'em. Film caps are the supplanter.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
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