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Originally Posted by runnerben
How do I go about checking the capacitors? I hope these are easyer to find then some parts.
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This article has basic information about identifying and replacing capacitors:
http://antiqueradio.org/recap.htm
It primarily talks about radios, but the principles are the same for TVs.
This page has links to various TV restoration case studies, which may also be helpful:
http://antiqueradio.org/restoration.htm
Replace the electrolytic capacitors first. They are critical to the power supply, and it's pointless to try diagnosing other problems until you know the power supply is healthy.
NOTE: Tube TVs have much higher voltage than old radios. Use extreme care whenever the bare chassis is powered up. A h-v shock can knock you across the workshop or kill you.
I would also replace all of the paper (and plastic-coated paper) capacitors. To check one, you need to unsolder one end of the capacitor and use a tester that applies the correct working voltage. (Checking with an ohmmeter is fairly useless, and you can't tell anything by simply looking at the cap.) It's less work to simply replace the cap without testing.
The majority of them will be bad, anyway. You can save yourself time and aggravation by replacing them now, while the chassis is on your workbench. Do not replace ceramic or mica capacitors unless you have a specific reason to believe that one is bad.
I usually check all resistors 1 megohm and higher in value, and replace any that are more than about 20% off tolerance. Smaller resistors are left alone unless, again, there's a specific reason to think that one is bad.
Be patient. TVs are more complex than old radios. There are more things to check and replace. In some circuits, it's critical to use exactly the same values for replacements.
Not to be a wet blanket, but I would not attempt this project until you get your hands on the schematic. You can doublecheck the values of components against the schematic & parts list, and check off each component as you replace it. That could help you find your way back to Kansas if you make a wiring mistake somewhere along the line.
Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html