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Lisa 2/10 Raster No Video / Clicking Speaker
Posted by: Pugy365 on 2026-03-06 17:16:21 Hi all, I’m working on bringing up an Apple Lisa 2/10 with CPU board 820-4009-B. The machine appears partially alive but does not produce any usable video output besides a raster and has the clicking speaker. I’ve removed the floppy and widget drive for testing. I have already did a recap on the CPU and I/O board and have had no change in behavior. No damage to the boards as this does not have the battery pack. Also plugged in an Apple /// monitor and it behaves basically the same as the internal one. Looking for some advice as I’m wondering if this is video RAM related, I did reseat them but no difference. Current symptoms • CRT powers up and produces a stable raster • Screen shows horizontal bands/interference but no text or graphics • No startup message or errors on the screen • Constant click when powered on • Behavior is unchanged even with RAM removed, clicking stops when I/O board removed Troubleshooting done so far CPU Reset line tested with oscilloscope: Goes high at power-up and remains stable Drops correctly when reset button is pressed Clock signals appear present and active ROM Both ROM chips removed and verified using programmer ROMs match known good Lisa ROM
Posted by: Pugy365 on 2026-03-08 06:09:43 Progress update, after using some deoxit on the video board trim pots I was now able to get a stable image. Image is below but basically only a capital H but still the constant speaker clicking. I believe I should see the self test at this point but I don’t get that far. I do at this point have a keyboard, mouse and floppy disk connected.
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