g07 hv shutdown

tron guy

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I have been following the flow chart from randy fromm trying to get this figured out.

This is a recapped chassis with new flyback, hot, and I just replaced the voltage regulator.

It got me to the point of pulling X701. When I pulled it the monitor worked.

Basically following the chart it led me to the point where it said bad VR, well it wasnt' bad but since I had it out I replaced it anyway. It also said test all 900's. I pulled, tested and replaced X701, X901 and X902, none of them were bad, but the parts are cheap and I had them out so I replaced them.

what should I be looking at next?

I did happen to put the meter on the b+ pot when I had the chassis out and it adjusted from 000 up to 1000 so I think that pot is good.
 
When it says test all 900's, it means the resistors and diodes too, check the resistors in the 900 area one of them has probably burnt up on you. You can test them in circuit quick an dirty, just look for a resistor that measures in circuit higher than it should. So for instance if it says it's a 3k resitor or something, and it measures 2k in circuit, that's likely good (the resistance is low because of how it's wired in circuit)... if it reads 4k, however, it's bad because the highest the resistance would ever be is the value of the resistor itself.

Hope that makes sense
 
what's the value of R908?


I have my analog meter out testing and I'm using a resistor calculator online, but man this shit is frustrating. Do I need to pull these all out of circuit to measure them?
 
well to the best of my ability and lack of training/knowledge on this stinking thing :) I think I've determined that these are good:
resistors: 907,912,910,904,903,905 and D905

I think the measurements that are bad are:
R908 I think according to the calculator this value is: 47k ohms
R906 I think value is: 150 k ohms

can someone confirm or deny the values on the 2 above resistors.
 
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Just download a copy of the schematic and you can work right through the resistors using the schematic. It shows where they connect and what all the values are.
 
ok radio shack and frys have the 47k ohm resistor in stock but neither have the 150k ohm resistor.


I have some 100k ohm resistors, so I suppose I can twist together a 100k and a 47k and even a 3k if I have one to replace it huh? Not in a daisy chain but twisted together?
 
well I scored some 47k ohm resistors from the shack and got to work.

I even tested R908 in circuit (analog meter) with this particular chassis and a working one, same exact readings in circuit. Pulled R908 from the bad chassis and it was dead. That made me wonder what the hell was going on so I puled R908 from the good chassis, it was good.

Anyway, replaced R908 and now she works, I have my B+ at about 121.2 do I really need to mess with that? I had it adjusted between 118 and 121 but didn't nail it perfect at 120 yet.

I did for the record pull R906 as well, and it measured good out of circuit. I am clearly a rookie with an analog meter and how it works, but the reason I got one was basically because Bob and others said I could measure things in circuit with it. guess not

anyway, special thanks to ghostnuke for the in thread and pm conversation we had, and thank you to the others who helped me with this one.

boom!
 
121 is perfect, don't worry about it.

On resistors, believe it or not you can't put them together like that, but if you put them end to end it works. If you put them beside each other, it actually reduces the resistance, it's really counter intuitive.

So if you wanted to make a 150k, you'd do a 100k, tied to the end of a 47k, tied to the end of a 3k, and end up with 150 k. If you put them beside each other, it'd end up being something like 1K instead of 150k!
 
121 is perfect, don't worry about it.

On resistors, believe it or not you can't put them together like that, but if you put them end to end it works. If you put them beside each other, it actually reduces the resistance, it's really counter intuitive.

So if you wanted to make a 150k, you'd do a 100k, tied to the end of a 47k, tied to the end of a 3k, and end up with 150 k. If you put them beside each other, it'd end up being something like 1K instead of 150k!

I had a 50% chance of remembering it correctly, lol. I'm glad 906 was good so I didn't have to mess around with that. I assume that a 100k and a 47k would have sufficed for replacing the 150k anyway
 
You can think of resistors like pipes of different diameters with water (current) flowing through them. The higher the value, the smaller the pipe.

More pipes, more water flow.

Longer pipes, same amount of water flow.
 
You can think of resistors like pipes of different diameters with water (current) flowing through them. The higher the value, the smaller the pipe.

More pipes, more water flow.

Longer pipes, same amount of water flow.

tsup brick top!
 
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