Recently I fixed an old Sinclair ZX 81 computer and had some good feedback so I thought I would post my experience of getting a less well know Sinclair computer working. The Sinclair QL was launched in 1984 as Sinclair’s push into business but it failed to make much of an impression in the market and was discontinued by Amstrad after they purchased the Sinclair brand.
I recently got my hands on one that wasn’t working and I set about getting it up and running. When a QL is powered up it prompts for a connection to a TV or a monitor which you select by pressing F1 or F2, on my QL I couldn’t get it to go past the display selection screen. I opened up the QL and lifting the keyboard I could see straight away there was a problem with the ribbon that connects the keyboard to the QL, as with the ZX81 the membrane is extremely fragile and on mine the metal strips having worn away. Unlike my fix for the ZX81 I couldn’t trim the end of the connectors to get it working, this would need a new membrane. Amazingly you can still buy brand new keyboard membranes for the QL, rwapsoftware.co.uk (via sellmyretro.com) make membranes for most Sinclair computers and a brand new QL membrane costs £14.
Changing the membrane is very easy, you open up the QL and then remove the screws from the back plate, you then swap the membrane and plug back into the main board. I did all this and hey presto the QL brought up the F1, F2 screen and I could select the monitor option. So all the keys now work and I was able to get a program loaded from one of the Microdrives, the primary Microdrive doesn’t work but that is to be expected as they were very unreliable even when new. So if anybody has any tips on getting them working let me know.