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Murf, it's your radio and your choice to make - the argument over recapping all at once, or doing it one at a time and testing will never be solved. That said, I restored a Philco that had the same issues that you are having... the problem turned out to be a bakelite cap off the tone control. I hadn't restuffed it yet. Since then, my thoughts are... they got to be replaced anyway, so might as well get it done before I start troubleshooting. But like I said, it's your call and feel free to disagree with me. I respect both ways of looking at it. I just see that you are trying to buy a working chassis now... and it seems like a waste of money when you haven't even recapped this one yet. Cart before the horse kinda thing..
The artist formerly known as Puhpow! 8)
(This post was last modified: 09-03-2013, 09:49 AM by
Jamie.)
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The problem with totally recapping a non working radio is that you may put all the effort into replacing the caps, only to find that there is a bad part which is not available or economically feasible to replace. Sometimes it just does not make sense to try to rebuild a common chassis when you could find a complete working replacement easily.
In my experience, troubleshooting first after replacing the filter caps and checking the B+ line for shorts is a better way to go. This has been my approach and others may have a different opinion.
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I do agree with you, and that is the proper order of doing things.... but the level of experience and the knowledge of the person doing the trouble shooting will determine the outcome of that method. And most often, that method leads to a bad cap, resistor or tube anyway.. For guys who are old pros, that is surely the right way to do it. And Mondial, believe me, I have a lot of respect for you and what you say.
When you are a beginner, or don't have a lot of trouble shooting experience, trouble shooting is often a matter of a process of elimination... if a beginner can eliminate caps, resistors and tubes as a possible problem, then it's easier to move on and find the real trouble. And once you replace caps, check resistors and tubes, 95% of the time, there is no trouble to left to look for.
I'm not saying Murf is a beginner, but he said the suggestions sounded "a little technical"...To me, that is a clue. I just hate to see him buy a new chassis when he might not have to do that. I am a beginner myself, but I am learning quickly.
The artist formerly known as Puhpow! 8)
(This post was last modified: 09-03-2013, 11:29 AM by
Jamie.)
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Murf, when troubleshooting a nonworking radio, there are two quick checks to do first. First, with the volume control turned up, touch the center terminal of the volume control with your finger (careful, don't touch the switch terminals). You should hear a loud hum. If not, you have problem in the audio section or the power supply. Next, place a working radio next to the one you are troubleshooting, with dial set to around 1500. Set the dial of the nonworking radio to about 1000 and rock it back and forth. You should hear whistling that changes pitch as you rock the dial. If not, your local oscillator is not working. By performing these two checks, you have tested over one half of the circuitry of your radio. If the radio passes both checks, the next thing to do is, check the voltages at the tube sockets and compare them to the service information.
Steve
M R Radios C M Tubes
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Murf
I may be late to chime in but - do the recap, man, listen to the folks who told you to do it - they are all very experienced people and will not tell you wrong. It may or may not be pertinent to your problems but it will take many questions off the table.
And the worst thing about skipping the recap - you might actually get it to work and then you might be tempted to skip it altogether. And this would be really bad.
Mike.
(This post was last modified: 09-03-2013, 02:13 PM by
morzh.)
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All very useful bits of info.
THanks guy's.
ANd by the way, I am pretty green at this. HAve re-capped many and got them working good, but trouble shooting has always been my weak side.
Most of you pro's probably have done this for a living for many years, so naturally your advice would sound pretty technical for an old tool and die maker like me.
Your into schematics, where I am into very complex blueprints.
We all have our nich.
Anyway, you guy's do a great job of informing us who do it as a hobby.
Thanks guy's
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Thanks for posting this problem and it's solutions. For me it was worth printing out and keeping as I know I'll be in Murf's shoes one day.
Tom
