Amiga Roctec RF332C External Drive Repair

Arrived untested from Ebay.

It looked fairly clean so I gave it a test on the Amiga and the dreaded high pitch whirring grinding sound suggested there was either rocks inside or the belt had perished plus the Amiga just repsonded with disk unreadable. So as is per usual from Ebay just replace “Untested” with “Spares / repair” or “Banjaxed” or “Knackered” or “Go on then, just buy me sucker!”.

The case is easily removed by removing the 6 screws on the underside of the drive and sliding the top half of the case forward a few centimeters to allow the bottom half circuit board to lift slightly so you can slide the bottom case and the circuit board over the top case and the drive back through the top case.

Then just remove the cable connecter from drive.

First order of business was an inspection which revelead lots of belt bits like this.

Once all the remaining belt parts are removed thoroughly clean the spindles and motor shaft end with isopropyl to remove all the remaining rubber residue.

I didn’t fancy taking the whole thing to pieces to install a new belt so just removed the motor and bracket which is all thats needed.

I also removed the motor leads so take note of where the red and black leads go in the photo above.

This gives easy access to the aluminium capacitors which I replaced as they leak horrible juice which can damage the circuit board.

The drive unit is a Citizen U0DC-12A I ordered a new belt which is commonly available on ebay based on help from this page. It appears the Sam Coupe used the same drive

I originally ordered a AVBELT5 as recommended from CPC but the belt was slipping so ordered a AVBELT4 from ebay which worked perfectly. CPC was quite a bit more expensive but arrived very quickly. Just search on ebay/google for your dimension e.g FLAT BELT 69mm x 3.0mm x 0.6mm. but beware it seems AVBELT5 is the most common just not in my case. The AVBELT5 is the same as a Sinclair +3 drive belt.

AVBELT4 – Flat Section Drive Belt 69.0 x 3.0 x 0.6mm Rubber
AVBELT5 – Flat Section Drive Belt 71.0 x 2.8 x 0.6mm Rubber
AVBELT6 – Flat Section Drive Belt 72.0 x 3.5 x 0.5mm Rubber

The required aluminium capacitors depend on which board you have. There are two varieties so carefully compare yours with the photos in the worldofsam page link above.

Mine was the second variety requiring 22uF 16v x 2, 2.2uF 35v, 10uF 16v

To install the new belt in its best to remove the motor and thread in the belt with tweezers then loosely put the motor in last and with tweezers pull the belt over the motor shaft and then screw it in.

The belt is installed as below in yellow with the red circle being the shiny little metal spindle.

Don’t forget to carefully clean the drive heads with some isopropyl before reassembly. The top head(shiny square in the middle and to the left above) can be lifted very slightly to more easily clean the heads with a cotton bud. The head is a small piece of white plastic with a black line through it.

And… another drive lives