I recently got a FB100 disk drive. I disassembled it to check the belt, which seemed...okay...
I didn't put it all back together (fool me once, shame on you...) On my T102 with TS-DOS (in ROM), it recognized the drive. I put in a disk (DSDD) and TS-DOS said "not-formatted", as expected. So I formatted, but after crunching for a while it said "Communication error". I tried with another DSDD disk that I formatted on my laptop and it had the same result. Since I hadn't reassembled it completely, during the format, I could see the head moving so I knew at least the signalling was working. Also, possibly significantly, during the format it seemed that the upper pad arm (opposite the read/write head) wasn't touching the disk. Is this normal? More background: after the partial reassembly, I tried inserting a disk and it didn't slot in, and I may have pushed a little too hard. Turns out somehow the upper pad arm shaft was stuck under one of the metal tabs of the "disk holder assembly" so there was no way for a disk to go in. After fixing its location, I was able to easily insert a disk. Could the upper pad arm be misaligned, causing the communication error? Or could it just be an old belt, causing timing issues on the motor? Any additional debugging tips would be appreciated. ( https://archive.org/details/tandy-portable-disk-drive-service-manual-26-3808/page/n4/mode/1up is my reference.)
