This is the output of the head amplifier for head 3 on cylinder 23. The narrow spikes are the sector headers. This is the track where the overwrite stopped. Somewhat over half of the sectors were overwritten. The sectors are interleaved so the sectors sequentially on the track are 0 16 1 17 etc. At the beginning only the sector headers are left since both sectors 0 and 16 were overwritten. Further down the track every other sector still has data since for example sector 5 was overwritten but 21 wasn't. Normally overwrite would still have transitions since MFM data is required to have transitions at least every 200 nanoseconds. Seeing just low level noise the head was writing but no MFM data was being written. When I moved the heads off the center of the track transitions didn't start to show up until the head was picking up the adjacent track so it was not the data was written with the heads in the wrong location.
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