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smoked resistor
#1

Hello people..This is my first post  but have read a lot of everyones posts and find lots of good info.Im restoring a hippo 46-420 i have changed all caps but when i powered up the radio through a bulb dimmer after a few moments a 45 ohms resistor started smoking.The light bulb was dimed down and steady but imedietly shut the radio down.I checked the resistince after the fact and it was still reading 47 ohms ? You would think that it was shot? Its a metal type resistor  Part 32-3432  ..= R 100  On the drawings it shows directly going to the 35zgt rectifier tube but on the radio it goes to the 7c7 rf tube pin 8  the heater pin then the other end goes to pin 8 on 7B7 IF tube. Would this have anything to do with the resistor smoking? It looks like they are all hooked up to all the heater pins anyways.The part in question is at the very top of the photo,The long metal cased one.Im pretty new to all this so any info would be appeciated.. Icon_e_confused


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#2

Check ALL tubes. Your rectifier may be shot.

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
#3

That candohm is a series dropping resistor for the tube heaters, it's a wire wound and is unlikely to be bad since it's a stand alone resistor with no taps. It is possible that it is shorting to that chassis, but a resistance check between the resistor and the chassis would reveal that. 
Regards
Arran




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