Getting the PlusD to work on a ZX Spectrum +2A / +2B / +3

When using PlusD disk interface on the +2A / +2B / +3, a so-called 'Fixer' board is needed.

This Fixer puts the ROM select signal coming from the PlusD to the corresponding ROM select lines on the +2A / +2B / +3.

Another issue is the speed the ZX Spectrum +2A / +2B / +3 boots up: it seems to be too fast for some PlusD's.

This is caused by the reset capacitor within the +2A / +2B / +3.

According to +3 schematics, there should be a 10uF reset capacitor, but there is a 1uF one used.

Due to this and because of aging, that original 1uF reset capacitor has far too low capacitance to do its job correctly.

I recommend replacing this with a 4.7uF or 10uF capacitor when having troubles with the PlusD.

Ben Versteeg