Back in the 1980's there existed a 3" Disc system championed by Amstrad in its CPC, PCW and Sinclair ZX Spectrum +3, computers as well as a few other more obscure users. The problem is, over 30 years on, and it is very unusual to find one of these drives in functioning order that hasn't been repaired, and the majority of the time, the problem is the flat rubber belt has disintegrated and or turned into a pile of goo in the drive mechanism. Well, there are plenty of places you can find advice on how to replace these belts (you found this, you'll find that), including cleaning up the gooey mess left by the previous belt. The problem is, these belts are hard enough to find; also the belt measurements are hard to find. In order to restore an old drive, I took the old belt, or what was left of it, and measured it then took a gamble with a similar looking belt I saw on CPC Farnell. It worked.
The important bit:
The dimensions of this belt are as follows: 69mm diameter x 3mm width x 0.6mm thick The belt can be found on CPC Farnell's website by searching for AVBELT4. EDIT: I have since found a usenet post from 1996 by the venerable Emmanuel Roussin, here, which says the following: So the belts I bought, while OK, are a bit on the tight side, however, they do not feel overstretched. CPC do sell a much closer fit in the AVBELT6 which is 72.0mm x 3.5mm x 0.5mm, and a little cheaper. This post is intended to help others find a source of these belts and for me to remind myself.
