Recent content by trondl

I’ve now swapped 1 to 3 and 2 to 4 which did fail but no address revealed. Swapping 1 to 2 and 3 to 4 was so unstable that it crashed before any reveals. Now it’s back in the positions they had and the address is still the same: $6CDF6 I have a strong hunch that the stick holding that address is...

I may have smoked out a fault! Getting MacTest Pro from the iso to an 800kb floppy is a long story, so I won’t bother you with that. It involved the .cdr file format. MTP on the Long RAM test has failed on the same address twice: $6CDF6 This is a 4x1Mb system. Which RAM stick would that be...

Hi again from Norway! This time, I'm trying to fix my SE (first "revision" with resistor RAM config) as I have resurrected the SE/30 so I can make proper 800kb floppies ( https://68kmla.org/bb/index.php?threads/se-30-crt-vertical-foldover-woes.50130/ ). Long story short, the SE's previous owner...

Guess what! When you're 99.9% sure you didn't cause any shorts while rewflowing, make sure to make that a 100%. The tiniest of solder bridges I've experienced before... Size of a hair. Also, when insisting on working in cramped conditions by having the analog board with the anode cap still...

Thanks for the input obsolete ! I'll definitely dig deeper into the R7 / R8 situation. Doesn't make sense to me either. Also, thanks for confirming my non-panic regarding UH7. I was trying to find a schematic that easily showed what I had shorted, but my hunch was the main clock and something...

Had to take the scope out. This is measured at the yoke connector board side, pin 1 Blue. According to the BOMARC schematics, it's supposed to look like a falling sawtooth, which it certainly isn't. Something tells me there is something very wrong here, but where in the vertical circuit? Very...

Or is the chip in the image actually called UG7?

Forgot to mention that I did try another SE board in it. Same behaviour.

Hi, and thanks for your time and knowledge! Struggling a bit with this foldover issue as seen here: As you can see, it starts "drawing" before the beam has returned to its correct position, therefore the top lines are inverted (verified with the mouse pointer). Also, the scan lines start...

Hi from Norway! I just registered to this forum just to say THANKS to the person responsible for sharing the 4.1.5 image. I’ve been pulling my hair and chased my own tail for years due to a bad dump of 4.1.5 that I received from somewhere else. Always ended up with a default catch fff00700...