Hot CLUT DAC on LCII ok?

RetroTechGuy

New Tinkerer
Feb 25, 2023
11
0
1
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I have an LC II logic board that won’t show an image. I’ve seen that others have had the same problems, but I’ve recapped the board and tried with a PRAM battery.

The hard drive spins up and the monitor leaves stand-by but there is no chime.

I’ve noticed that the UJ10 chip next to the video connector gets really hot, too hot to touch after a while. This chip is also labeled as CLUT DAC.

Does anyone know of this is normal? I’m considering trying to replace this chip if it doesn’t run red-hot on other machines.
 

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melkab

New Tinkerer
Mar 1, 2024
1
0
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Did you ever find out if this chip being hot was OK or not? Have an LC II with the exact same symptoms (no chime, no video) and this chip is hot on my machine too.
 

GiGaBiTe

Tinkerer
Feb 6, 2022
33
29
18
In normal operation, those chips get mildly warm, but not burning hot. I suspect your chip is most likely dead.