exxos's Atari, Amiga & retro forum

Hello,

I just installed the 230V PSU in one of my STe ( 520 STe C025913-038 DMA + MC68HC000 + Exxos PSU + 4Mo + TOS 1.62/206 switcher + HxC USB floppy + RGB2HDMI v20210529 ) and since then, it starts to a black screen (green led, no orange floppy activity). After a reset it boots fine.

Any idea about what may be the problem ?

I also seem to still have corruptions on some UltraSatan operations and certain floppy transfers, but I'm not positive on this as I'm not super confident about this machine health. Is there a sure-fire software way to test this ?

I have a second PSU for my second STe, but didn't want tu upgrade before understanding my issue on the first machine.

And finally, the https://www.exxosforum.co.uk/atari/last/ ... htm#PSUFIT page seems outdated. the 2019 PSU version doesn't need drilling, termal paste or removing of the insulating plastic sheet and there is no mention about the connection of the non-uses transformer cables (but again I may have missed something obvious).

You need to replace the reset capacitors, you'll find information under MANDATORY FIXES page.

The DMA is a proper rabbit-hole, under mandatory fixes you will find information about replacing all the bus resistors, WD chip pullups & floppy resistor mod. All of these need to be done as a base-line before any more troubleshooting can be done. These are all things that affect the DMA & floppy. Also of course, clean the floppy drive 8-)

You Need to do the reset fix in the mandatory fixes list.

As for the PSU link, the store link takes you direct to the correct page.https://www.exxosforum.co.uk/forum/viewt ... f=9&t=1245

I added a 22µF to C100, it seems to fix the boot issue. Thank you both.

I have not the proper resistor network handy, that fix will have to wait :(

The floppy drive is replaced by a usb Adaptor, that's at least one think I won't have to check :)

Thank you again for your help and the resources you made available (I confess I got a bit lost in the amount of versions of PSU mounting docs, I didn't even see the mentioned link at purchase).

(before 22µF cap)

Thanks for the great pictures @pixelk. Next time please attach pictures to your post (usually you can just drag into the editor) and then use the "Place inline" button in the attachments tab below the editor. That way we won't ever lose your pictures in the future, should an external host happen to go down. Thanks!

I have rehosted the pictures in your post. No need for you to do anything.