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Old 08-15-2018, 11:03 PM
mrjukebox160 mrjukebox160 is offline
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The part that's missing is called a thermistor and is why it's dead. For testing just use a 5 watt or larger 15 ohm resistor.
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Old 08-15-2018, 11:09 PM
Sealtest Sealtest is offline
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Quote:
Originally Posted by mrjukebox160 View Post
The part that's missing is called a thermistor and is why it's dead. For testing just use a 5 watt or larger 15 ohm resistor.
Is the thermistor similar to a round black fridge magnet? I found an odd piece in the bottom of the casing and was wondering what it was.

Also anyone know what the black stuff is that peeling off the back of the CRT and making a mess everywhere?
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Old 08-16-2018, 09:26 AM
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bandersen bandersen is offline
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Quote:
Originally Posted by Sealtest View Post
Is the thermistor similar to a round black fridge magnet? I found an odd piece in the bottom of the casing and was wondering what it was.

Also anyone know what the black stuff is that peeling off the back of the CRT and making a mess everywhere?
Yes. A thermistor is typically a black disc. round the size of a nickel but thicker.

The black CRT coating is called "aquadag" It's conductive and grounded to form a capacitor thet filters the high voltage supply. You should recoat it once you've got the set working with something called "slip plate".

https://www.slipplate.com/product/slip-plate-aerosol
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Old 08-16-2018, 11:49 AM
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Notimetolooz Notimetolooz is offline
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MG Chemical makes a similar product. It also come in a spray can.
Here is a version that you brush on.
https://www.amazon.com/MG-Chemicals-..._&dpSrc=detail
The aquadag falling off the CRTS of RCA sets of that era is common, I've got one or two sets with that problem.

Thermistors frequently go bad. The fact that your's is unplugged might mean there is other problems.
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