I said earlier that the 84MB of disc space I had created on the first format was an overestimate. This was because I was formatting them to RLL format which is higher density than MFM format. The Adaptec ACB-4000 can only support MFM recording so I was in fact falsely creating more space than was physically available. The format routines available for the BBC do not detect this, by the way, but you would find out eventually when you get disc errors after trying to access logical sectors that are not physically present on the disc!
The image above shows the result of the format using MFM encoding. Still 59MB which is pretty impressive in my opinion!
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