Lisa 2/10 No boot, Raster, Speaker Clicking

[sigma7]

Thanks for the tip, I probed U68-LS132 Pin 3 and see basically the same thing.

Sounds like you've narrowed it down a lot!

Suggestions:

Check for physical damage to the transistors as they can be bent/broken by rough handling.

Check for +12V at R4.

Swap in another crystal (even a different frequency) to see if the rest of the oscillator circuit works.

[pugy365]

The transistors looked ok but the Hfe values on my tester were very low on Q1 compared to the Q2. Since I had some that would work I replaced the Q1 & Q2 transistors and had no change in my probe measurements or behavior of the machine. I also confirmed 12v+ at the R4 resistor, Im not sure I have a crystal on hand, but going to look and I ordered a new 16Mhz one which will be here in a couple days.