If the fuse is still good does that mean the flyback is good

dyno

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If the fuse is still good does that mean the flyback is good

If the fuse on the chassis is not blown does that mean the flyback is still good? Have a sampo kgr that doesn't power up and no neck glow but the fuse is good. Am I correct in assuming the flyback is still good.
 
If the fuse on the chassis is not blown does that mean the flyback is still good? Have a sampo kgr that doesn't power up and no neck glow but the fuse is good. Am I correct in assuming the flyback is still good.

No.
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I have looked at the flyback and it has no signs of damage to it, no cracks or anything. Don't they usually show some sign of damage you can see if they are bad?
 
When you looked at the flyback, did you:

1. Completely remove it from the board?
2. Subject it to an inspection of all sides, looking for cracks, holes, distortions of the case?

If you didn't, you didn't inspect the flyback.

You could have a pinhole blowout of the coil.

Also, did you actually remove the fuse and meter it for ohms, out of the circuit? Did you check that you actually have power to the monitor, and that it is getting what it expects to get?

Have you pulled the chassis yet, looking for cracked solder joints?

There is a ton of stuff you have to do first.
 
Yes pull flyback of board and it looks fine and I did use a meter to check the fuse and it is good. Checked the board for cracked solder joints but will check again. There is power getting to the monitor, have to check what the voltage is at still on the chassis
 
since todays chassis use isolation transformers, the only thing a good fuse will tell you is there isn't a short in the power supply section.
 
That depends on the chassis and whether the PS section is isolated from the deflection section.

If you don't see cracks or pinholes in your flyback, then I doubt it is your problem. Many different things can lead to a dead monitor - regardless of whether the fuse is blown or not...
 
Its a sampo kgr 1901, I am hoping the flyback is still good because I can't get a replacement unless I get a used chassis and they are hard to come by. The flyback on my first sampo blew a hole, it took me some time to find a used chassis. The second one was missing the Hot and the ic so I took them off my 1st chassis and the 2nd one fired up but showed no picture then went into high voltage shutdown so I tired to adjust the B+ which brought it back briefly then it shut down for good. I then took the flyback off the 2nd and put it on my 1st chassis and tired to fire it up but got nothing and there is power getting to the chassis from the iso transformer and the fuse isn't blowing but nothing is happening. I haven't had the chance yet to test the B+ on it, hopefully in a day or 2 I can get to that. Anyone now where to test for the B+ on a sampo kgr 1901? Looked at the manual but it doesn't really say from what I read. I also was contacted the other day by a KLOV memeber that he had a Sampo KGR 1901 chassis if I wanted it so I bought it from him and am just waiting for it to arrive.
 
Something went open in the circuit. Get it the board, and look at the solder joints. Anything that looks the least bit questionable - re-flow.

Then start testing point to point, trying to find the break. Something has to be open for the symptoms you are experiencing.
 
Finally got back to working on the chassis and turns out the HOT was no good. It had a 2sd871 HOT which I replaced with a 2sd870 because I had one around and the monitor works. I made sure the HOTs were interchangable before I did so, the only difference is the 871 is 6 amp and the 870 is a 5 amp. The monitor fires up now but the picture is not full size, tried to adjust with no luck. I do have a cap kit for it which will be my next step.
 
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