Zenith transoceanic H500

[radio nut]

Hello, i recently bought one of these sets from Ebay in restored condition. It worked pretty well, and the I bought the reproduction battery pack and loaded it with batteries and tried it out...At first it really performed much better I believe because there is no interference in the power cord. But it started going quiet until the tuning capacitor is tapped lightly. I did use liquid deoxit on the tube pins and antennae connection. I even tried deoxit in the tuning cap wipers...then QD electronics spray cleaner. I did see a little black stuff by the wipers and tried a qtip with alcohol on it..i did get some black stuff off but now all i get is maybe 2 local stations and loud static when i try to tune other stations....ok now what do I do?

[vortalexfan]

First of all, you NEVER use any sort of chemical sprays on the tuning condensers on these old radios, because you'll ruin its ability to conduct properly, the only thing you should use to clean the "fins" of the tuning capacitors is compressed air, by using the DE-OXIT on the Tuning capacitor like you did, you may have ruined the tuning capacitor.

I would of first checked some of the tubes to make sure they didn't go to air, or didn't go bad.

Also I would of taken the chassis out of the cabinet and made sure the radio was actually restored, because there have been cases where people have been selling old radios on ebay where they claim to have "restored" them, when in reality all they did was clean the case up and and clean the chassis up and that was it, if you still see old paper capacitors (or old bumblebee caps) under the chassis then you know it wasn't actually restored.

I hope this helps.

[Electronic M]

Sometimes the plates get bent and rub each other shorting the tuning cap... usually fixable but first one you have to find it.

Another way to clean tuning caps is to take a strip of copy paper and slip it between the plate.
I don't think the cleaning sprays used hurt it. I've used tuner cleaner on tube era tuning caps and had it work fine....YMMV.

[Zenith26kc20]

My H500 was drenched by rain a long time ago when I was in the army. I let it dry out and after a day or so it came back to life. I still have and use it. I would think the tuning capacitor will dry out after a few days if you sprayed it with cleaner. What worries me is you mentioned poor sensitivity and static. You may have silver mica disease damage in the IF transformers. Not a impossible repair if that is what is wrong but very tedious and great care is needed doing it.

[vortalexfan]

Originally Posted by Electronic M

Sometimes the plates get bent and rub each other shorting the tuning cap... usually fixable but first one you have to find it.

Another way to clean tuning caps is to take a strip of copy paper and slip it between the plate.
I don't think the cleaning sprays used hurt it. I've used tuner cleaner on tube era tuning caps and had it work fine....YMMV.

I only mentioned the tidbit about not using cleaning solvents on the tuning capacitors because I have heard differing opinions on that topic, so that's why I brought it up, I wasn't trying to be mean or disrespectful.