Questions, Advice and Brainstorming requested for a Sanyo 20EZ

Black Matrix

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Questions, Advice and Brainstorming requested for a Sanyo 20EZ

Hey all,
I have this 20EZ project I've been working on, and I thought you guys might have some insight. When I started, it had exploded the B+filter cap, was missing some pots and the 300 mA fuse. I've since capped it, replaced the B+ filter cap and changed +B pot, put the missing pots back in, and replaced the 300mA fuse .

Today, I powered it up for the first test, no crackle of the HV charging up. It just had a low hum, B+ was reading less than 2 volts and then 15-30 seconds later, it blew the small fuse. I don't think it had any picture at all.

So here are my questions.

1. Is the 300Ma DC fuse the F301 or the F302. I don't have the chassis in front of me and its hard to follow the flow chart without knowing which is which.

2. I read some older posts that would imply that I may have a problem with the HOT. Anyone know a a good source for these 2SD1090 (unless I'm mistaken). And I hate to ask, but I'm still not 100% on how to test these HOTs. I thought I had tested the Hot on this and it had tested out good. So I'm either doing it wrong or I have another problem.....Like a bad fly back. Haven't tested the diodes (D601-D604). So if anyone knows a good diagram, or youtube vid showing how to test the HOT, it would be helpful. Or just some really simple instructions. Don't mean to be an idiot here, but sometimes you got to go with what you know. ;)

3. Anyone have any theories, as to what my problems are. Advice you think will help. Funny anecdotes that you think will keep my spirits up till I figure this out.....Couldn't hurt.

And as always, many thanks in advance.
 
I really must be a dumbass. I retrieved the chassis today so that I can inspect things once again. Here's what I think many of my problems were. I was under the impression that the SD1090 Transistor was the HOT, which was why all the instructions on how to test made no sense whatsoever. After I thought about it today at work, it dawned on me that the instructions on how to test the hot was for a bottle cap transistor. So, I tested the 2SD993A on the side of the metal chassis and sure enough its toast. Shorted out. So I guess the next question would be,

Would a bad fly back burn up the HOT, or is it likely that the HOT is my only problem. Again, this thing had a huge hole in the side of the filter cap. And now I know the 2SD993A transistor is bad.

Any thoughts.

EDIT:
And after checking Bobs Roberts, I found no 2SD993A, but he does have a listing for 2SD869 Nintendo HOT. So I went back and looked at the schematics(closely). It shows 3 different parts numbers including the 2SD869.

Can I assume that they will all interchange or was different HOTs for different sized monitors. If they will interchange, I may be ordering a flyback and HOT and finishing this thing up very soon.
 
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