BeebMaster - BBC Model B Disc Upgrade
BeebMaster

Fitting a
disc upgrade



The following links positions must be ensured by moving the link jumpers where appropriate:

S18 - North
S19 - East
S20 - North
S21 - this is a square bank of four pins. The two link jumpers must be set East-West, ie. facing horizontally and not vertically.
S22 - North
S32 - West
S33 - West

You may find that all these links are already in the correct positions. On an issue 7 board, links 18 & 19 are solder links which are already set to the correct positions. The other links are jumpers which have already been correctly set.

It may also be worth checking the following links. These are all tracks on the circuit board:

S4 - East
S10 - West
S27 - West

Link S10 is on the visible side of the circuit board but links S4 and S27 are made on the underside of the board so you will only need to take the circuit board out if there is a problem.