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[techknight]

Could be, but again.. it goes back to my previous post. 

 

[Sinclair]

Could be, but again.. it goes back to my previous post. 

ok, but you say too :

The only ever chance it could be the analog board, is if the back porch pulse is too wide and driving the CRT into cut-off for too long, thats generated by the flyback and feeds the vertical stage in a feedback format. 

TDA-1170N?

 

[techknight]

but the likelyhood of that is fairly small. Still possible, yes... but small... the circuitry is way too simple. Now if this were a color monitor, all bets are off... 

You need to try and find another logic board, even if its a regular SE. This will help point yourself in the right direction, otherwise I see you chasing your tail in circles all day long. 

Without that, the only other option is using a scope and watching the signals coming from the logic board, but then you need a known good board to compare the waveforms to. 

 

[Sinclair]

Thank you, but it isn't so easy for my find of another logic board for testing...

I think my only option is to find the solution without hurry and continue listening to expert opinion.

 

[TheWhiteFalcon]

Techknight is about as expert as it gets.

 

[Sinclair]

Of course, I do not put it in doubt.
 
It's just that I'd like to know more opinions

 

[CC_333]

You could try sending it to Uniserver. He's up there with techknight in the expert department, and he does really great work recapping everybody's boards (power supplies, logic boards, analog boards... he does it all!), and he may be able to help you out with your current problem as well.

maccaps.com is his web site, where he has more detailed information, plus lots of other helpful materials that may be of some benefit (including a PDF of the Dead Mac Scrolls, which is an invaluable book to have around for troubleshooting purposes).

c

 

[Sinclair]

Nice to know it!
 
Currently I have recapped both boards, not the power supply but I think don't there go the shots
 
Thank you.

 

[Sinclair]

My logic board recapped:

That these images serve also if you see something strange.

 

[techknight]

I have done all I can. Good luck!

 

[Sinclair]

Thank you.

 

[Sinclair]

So it was how it came to me.

 

[CC_333]

Wow! That's probably the dirtiest SE/30 board I've ever seen!

Anyway, Uniserver does more than just recaps, so just ask, and I'm sure he can work something out with you.

Good luck!

c

 

[Sinclair]

I'm all ears!!
 
Send my boards to thousands of miles I think that it is not viable.
 
Thank you.

 

[joethezombie]

Interesting to see the cap goo bleed through the dust.

 

[tanaquil]

Whoa. Where were they keeping that thing, inside a vacuum cleaner?

Good luck!

 

[Sinclair]

It was inside the case The accumulation of dirt come it by the fan with the years simply through use. Even so functions as the first day.

 

[Sinclair]

Hi my friends.
 
I replaced TDA1170 from the analogic board and the problem persists.
 
Also I made a screenshot and I have extracted the picture from the machine to view that really should be displayed:

 

 
 

I would like to locate an a solution without having to change the logic board, as this is unattainable for me.
 
New ideas are welcome.
 
Thank you.

 

[onlyonemac]

It's a long shot, but try changing the order of the SIMMs. Those are the long thin cards that rise up from the logic board, and there should be some kind of clips holding them in place. Release the clips and slide the card out. Take them all out and put them back in a different order. That will tell us if it is a faulty SIMM.

 

[Sinclair]

Thank you but but this long shot possibility was ruled out long time.