I have one of these which works great. Although they are out of stock this page gives an email address where you can contact the creator to see if any more can be made available.
https://www.bit-zeal.com/product/stupid-pet-tricks-module/3
Colin.
Another easy test just to eliminate it is to test the speed of the drives using the programs here:
https://www.zimmers.net/anonftp/pub/cbm/pet/utilities/8050diag35.d80.gz
Couple of other things that helped me with my 8050:
https://drive.google.com/file/d/1eAvu76XHwl1DJ5JybEvKGi4B3os7F3kl/view...
Do you know if the IEEE port is good? It would be handy to eliminate that if possible by using another device on that port successfully.
I have a working 8050 here (but not an 8032-SK) which I had trouble with and managed to fix OK.
Also the 8050 should really use Quad density diskettes...
I had to replace one of the ROMs (901468-11) on my 3040 (pretty much the same as a 4040). They're expensive to find a direct replacement so I used a 27128 EPROM and the adapter below:
https://myretrostore.co.uk/product/23xx/
Colin.
Ah. Apologies. If yours is this board then R758 and R759 both will have an effect on the brightness too:
https://www.nightfallcrew.com/wp-content/gallery/commodore-pet-8296-d/IMG_0465.jpg?81e99d
Colin.
With regard to the high levels of brightness - my 8032 monitor has the usual brightness knob to turn which pokes out of the back of the case, but also a smaller component on the monitor PCB (marked as R10 on the attached photograph) to turn which allowed more changes to the brightness.
Hope...
I believe this is the service manual with schematics.
https://www.zimmers.net/anonftp/pub/cbm/schematics/monitors/1084S-D1_PAL_Service_Manual_400413-01.pdf
Colin.
There seem to be some here (can't vouch for any of them myself though). Postage might not be kind though.
https://retro8bitshop.com/product/901887-01/
Colin.
I have purchased these from Dave Duke before, but he is in the UK so you will have to ask him for postage prices.
Contact him here
https://retromedics.com/
Or on Facebook.
Colin.
I've happily used a phone app (Strobily in my case, but there's plenty of others) to act as a 'proper' strobe when fixing one of my Commodore 8050 drives.
Colin.
I've just started to refurbish mine and three of the components have disintegrated. I'd be very grateful if you could find the time to take a look and let me know what they are. They are right by the power connector on the larger PCB.
Thanks very much.
Colin.
Lots more pictures here:
https://www.forum64.de/index.php?thread/61191-8026-restaurieren-oder-nicht/&postID=934760&highlight=8026%2Bolympia#post934760
And there's a German manual here:
https://archive.org/details/cbm8026_manual_german
But no schematics I can find.
Colin.
I've been pointed here - I have the same problem with an Intel 2716 '77 trying to read it with my Stag PP39. I ended up dumping the memory on the PET to a file and checking it on my PC (via a PET Disk Max 2.0). The Stag would read it consistently but it was rubbish.
I'll try my Arduino based...
Hi - I know this is an old thread but I'm picking one of these up next week and I was wondering if you got it working and did you find any manuals/schematics?
Thanks.
Colin,.
If you're checking power supply issues, take a quick look at the actual connector to the motherboard. My power issue on my 3016 was there and not with the pins itself. It only became obvious when I removed the connector - see attached photo.
Colin.