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Yes I suppose it is! However any sort of valuation would be greatly appreciate. I presume these machines are desirable.

Does anyone have an idea of the approximate value of this Umax clone? 

Thanks for your messages.  Yes I have learnt that you can be much more forceful with these drives than one might expect. I since have acquired two more widgets and have opened up all 3. Now on all 3 brakes release and all 3 have the glass optical grating intact and stuck down. One I think has a...

Thank you both for your help. A while back I ordered a ESR meter and it arrived today (took absolutely forever but I'm glad that its finally here). So I tested the capacitors C33 and C46 two capacitors involved in some shape or form from what I can tell with the +5B2 trace (I could be wrong...

Again silly question, are these electrolytic caps? I only have a store of surface mount electrolytics for recapping Mac logic boards which obviously wont work with the design of the Lisa I/O board.

Thank you both for your replies. I have tested this 2/10 I/O board and you're both absolutely right. The Lisa works fine with the 2/10 I/O board powering off and on normally therefore the problem is verified to be on the 2/5 I/O board. Will all traces verified as working in the affected area on...

Thanks for your reply. Just made a quick post on the forum to see if we can get a consensus. I feel this information may be of use to other Lisa 2/5 owners attempting to repair their I/O boards. 

Hi Lisa enthusiasts, I have a 2/5 which has I/O problems due to the corrosion and myself and a fellow member are trying to diagnose. I need to find out if the I/O board is the fault or potentially the edge connectors or traces on the motherboard. I don’t have a spare I/O board unfortunately.  ...

Fab thank you so much! I have ordered an ESR meter the same as the one you have as I really need one that works in circuit as so many of the capacitors around the COP’s chip have corroded solder joints so I cannot easily desolder them. In the meantime I was wondering if electrically speaking a...

If this is after a period of inactivity and it is left plugged in so the +5V standby is on the Lisa will always start up correctly If this is after a period of inactivity and it is NOT left plugged in so the +5V standby is off the Lisa will always startup without the soft switch being pressed...

So I tested all those traces for continuity and they are all good measuring almost zero ohms. I also swapped the COP421 chip (no difference) and swapped the 6522's (no difference). Really not sure where to check next as all the traces appear to be working normally. My only thought, and again...

Fab thank you very much! I will check those pins for continuity Just to confirm is pin 1 and pin 2 the 7417? Your board looks quite good actually Lots of the traces around the COPS chip look the normal colour.

This is a really silly question but where is U7F? Is it part of the COP421 chip? 

Another interesting find. The resistance of the trace between Q11 and pin 20 on the COP421 chip is reading as 15.2K, is this normal? Looking at the schematics I can’t see how this is. But as mentioned previously there is probably some component that I don’t understand how it works. But testing...

It was actually just a coincidence that the Lisa did what I said it did in my previous message. But it was a very convincing coincidence as I unplugged the parallel cable (stopped working) replugged it in (started working). I did that a couple times and it repeated the former perfectly every...

No not a problem at all. Actually comparing mine to this mine is not much better. My temporary fix was tin foil cellotaped to the solder joint above to bridge the gap between it and the gold contact. I didn’t want to modify the board permanently if it wasn’t going to improve the situation. Today...

Keyboard doesn't get registered either so although my board doesn't look too bad the traces are not doing so well. But will attempt to tackle the power switch issue first.

Thanks for your message. So I temporarily patched the trace just to test the Lisa and the power switch now partially works. But only to turn the computer off, and when it has finished turning the Lisa off it just pings back on. So from your post (if I have understood correctly) the +5V must be...

Hi all, Sorry to keep bring up my 2/5 saga but I think I may have found out what is wrong. Spoiler alert: I have no idea what I am doing so everything that follows this sentence is said with a deal of uncertainty. Unfortunately my area of speciality isn't electronics (as much as I would like it...

Thanks for your response. Unfortunately I am not doing well on any front. The Lisa is still having issues with powering on. Although I have narrowed down the issue somewhere on the I/O board. So I guess that’s progress. As for the widget. I genuinely have no clue where to even start. It’s such...