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Old 01-05-2016, 04:22 PM
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bandersen bandersen is offline
RCA 741PCS
 
Join Date: Mar 2009
Location: Chicago, IL
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Quote:
Originally Posted by bigaudioal View Post
Yep, L12 is inside the tuner. 0.1 ohm fil. choke. Do you just check the resistance on it like a resistor? If it is bad, is it replaceable?
Yes, it should read nearly 0 ohms. Replacemenets are available. You could also just short it out with a jumper while testing to eliminate it as a problem. I had a Motorola where several of the filament chokes had corroded and gone open.

Quote:
Testing pin three was very strange. With my multi-meter on the 20 VAC setting, I connected the ground wire to the chassis. Saw the meter register around 4 VAC. Then when I touched the other lead to pin 3 the volume on the set faded and then I saw smoke rising from a hole in chassis near where tuner is mounted. As soon as I removed the lead from pin three volume was restored. Reading was jumpy at best but did not get into double digits. I will test some of the other tube filaments to see that they are 6.3 vac.
...
I'm not sure I understand when you say you connected the ground lead and saw 4 VAC. What was the other lead connected to ? Was it not connected to anything ? What type of meter are you using - is it battery or AC powered ?

Touching a meter lead shouldn't cause something to smoke unless you were on the current or resistance scale by accident.
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