Sanyo testing only 7VDC

Atari The Jedi

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So I've been working on it 14 inch Sanyo which is very similar to its 20 inch big brother. I got it and it didn't work so what I've done to it so far has been changing q901, changed IC601, changed all the capacitors, HOT, B+, and I checked a couple of the resistors while in the process. It was spitting out 137VDC before I change the HOT now that I've changed it, it's only spitting out 7VDC. I'm unable to adjust it any higher or lower. I don't know what the next step is here looking at some of the charts it tells me to replace or check q901 and I've already done that. I don't know how to proceed from this point other than going back to the q901 and triple checking it again. All the parts I've got have come from Peter at APAR

Here is a picture of the q901 transistor. It's not labeled as such on the board but that's the best I could figure it was as you can see I've used new thermal paste and an insulator
 

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Seen your previous post about THE 5k pot,
Do a search for online for TM-157 SANYO Manual ,,,Can be helpful
discharge high voltage at CRT, AND TO BE SAFE AT B+ CAP AS WELL
check your new hot with the diode setting at each leg ,,base to collector and base to emitter.
try one thing at a time,, HOT, new B+ cap trace your steps, discharge always first....
 
That looks like a silpad behind the power transistor. You didn't use thermal paste with that did you? Those are meant to be used without thermal paste.

Jason
 
You got a Flyback you can throw in there? Also try another HOT, maybe a defective one. Weird you changed that part and the b+ tanked
 
So I've been working on it 14 inch Sanyo which is very similar to its 20 inch big brother. I got it and it didn't work so what I've done to it so far has been changing q901, changed IC601, changed all the capacitors, HOT, B+, and I checked a couple of the resistors while in the process. It was spitting out 137VDC before I change the HOT now that I've changed it, it's only spitting out 7VDC. I'm unable to adjust it any higher or lower. I don't know what the next step is here looking at some of the charts it tells me to replace or check q901 and I've already done that. I don't know how to proceed from this point other than going back to the q901 and triple checking it again. All the parts I've got have come from Peter at APAR

Here is a picture of the q901 transistor. It's not labeled as such on the board but that's the best I could figure it was as you can see I've used new thermal paste and an insulator
If you use a silpad, you don't need thermal paste.
 
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