Mac SE/30 booting but blank screen

LeSpameur

Member
Hi everyone,

For the past few days, my SE/30 hasn’t been displaying anything on the screen.


I completely cleaned the motherboard with isopropyl alcohol and replaced the capacitors.


It still boots and plays the startup chime, but nothing shows on the screen. I’m fairly certain the issue is with the video circuitry, but I don’t have an oscilloscope to check each signal.


I have a Rev 2 board for parts, but it’s showing a simasimac issue due to battery leakage.

Thanks in advance for your help!
 

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GreenBar0n

Well-known member
Nice work! What gave you the clue that it was the LS393 chip causing this? Was the chip visibly corroded?
 

finkmac

NORTHERN TELECOM
1735502646348.png

you can see it in the picture. it's rather corroded there. those ICs are in the direct path of the leaky lytic fluid. fairly common fault.
 
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