Microdrive refurbishment manual
- Replace the rubber roller (available from SellMyRetro.com)
- Add a 100pF capacitor to C7 and C9
- Replace the electrolytic capacitors right next to the 7805 (it’s ok to use e.g. 1uF instead of the 0.22 uF and 0.47uF ones).
When the Microdrive reads well but does not format well:
- Solder a 47nF capacitor on the power pins of its ULA.
When a Microdrive keeps spinning and the ZX Spectrum doesn’t respond anymore (to e.g. BREAK):
- Replace the 7805 of the Microdrive
More information at this World of Spectrum post.