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Macintosh 12" Monochrome Display M1050 - retrace lines
Posted by: kater on 2019-09-19 13:07:28
Macintosh 12" Monochrome Display M1050 

Picture faintly visible.

Moved thread from here:





Replaced caps and tested transistor PH2369 (fine on my cheapo tester).

No other result.

But i never gonna give you up. 🙂

thanks!

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Posted by: techknight on 2019-09-19 16:26:47
Before you fire that thing up, you must reconnect all the grounds back on the CRT board if you want to run it without the shield for troubleshooting. Otherwise you must reinstall and resolder the shield. 

From looking at the design, the ground shield is the ground that connects everything together, once removed, it will fail to work right. 
Posted by: kater on 2019-09-19 22:44:48
So it might be the ground shield was not properly soldered back? Seems i wasnt the first one opening it.

As i can't test the IC (with my knowledge), would it make sense to replace it just in case?

(I'd order some anyway for future use) 

Still having a hard time comparing ICs - could you recommend a similar one, preferable available in EU?

LM1201N

https://www.mouser.at/

thanks for your great support
Posted by: Roger on 2020-11-04 11:29:27
Hi,

have you been successful in the end with the 12'' monochrome display ?

I have a similar problem also with the 12'' Monochrome display.

So do you know if it exists at all anywhere out there a circuit diagram

for the main board of this 12'' monochrome display ?

Thank you for your answer to roger.seitz@web.de

Cheers

 Roger
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