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    What is making my 12x4 tube on my Pas2 to overheat?

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    bigalttd1

    Posts : 1
    Join date : 2012-01-08

    What is making my 12x4 tube on my Pas2 to overheat?

    Post by bigalttd1 on Sat Feb 04, 2012 11:04 am

    Is it a resistor and how do I test. This is new to me but since I can fix any appliance rebuild any kind of engine I'm going to learn this. Any help is greatly appreciated. Thanks!

    tubes4hifi
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    Posts : 1261
    Join date : 2008-11-30

    Re: What is making my 12x4 tube on my Pas2 to overheat?

    Post by tubes4hifi on Sat Feb 04, 2012 4:18 pm

    tell us more - all tubes run hot, how do you know it's overheating? Is it failing?
    Have you checked voltages on the circuit boards?
    There is about 400vdc next to the 12X4 tube on the "quad" cap. There are 3 resistors there, 2 10K and a 47K (if everything is original).
    One of the 10K resistors will drop 80v across it. The other 10K will drop about 20v. The 47K will drop about 80-100v.
    If those are all OK, most likely all is well.

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