In article <VA.0000291d.0b45b9a8@foxhill.co.uk>, Ian Oliver wrote:
However, I've now established that my disks are vanilla but in a sorry state.
Yes, you beauty! I know it's no longer anything to do with this list, but I have my data. I used a card called a "Catweasel" to pull off the raw data and parsed the sectors out of the dumps with a few hundred lines of Python. Lots of sector headers were missing/bad, sector 1 of tracks 1 to 34 claimed to be one track further along than it actually was (and was hence rejected), and data crc errors abounded. After multiple passes with different mfm thresholds and postcompensation settings, and using some more Python to merge good sectors from multiple files, I got enough of the disk images 100% to get what I needed. I'll keep working on the other disks of the set, but this other stuff isn't as important to me. Thanks all for being a sounding board. Regards Ian