Sinclair Calculator Repair


Hi All, I know this is not HP related, but I didn't know where else to turn. I am looking for help to repair a Sinclair Cambridge Scientific calculator, can anyone point me in the right direction please ?



Sorry to say that, but the Sinclair calculators were never constructed to last (nor to work as expected when new) - I'd clean all key and switch contacts and check battery contacts for corrosion or cold solder, too. A really "dead" unit is unlikely, but expect bouncy keys...


Thanks for the tips Frank, I will try them out. I do agree with you about Sinclair calcs being "a pile of ...", but this one is my wifes from her school days, so I wanted to get it going for her :-)



I do agree with you about Sinclair calcs being "a pile of ...",

That's a little harsh. Ammong other things the Sinclairs were truly shirt pocket size. No need to speculate on just how big the pockets in Bill Hewlett's shirts really were. And I think that the four volume library of programs for the Sinclair Cambridge Programmable was a impressive work for the time.

I have three. I will suggest one thing. You need to be sure that the 9 volt battery is in good condition. A battery which will run TI-30's, Business Analysts, etc., without a problem will give you fits in a Sinclair.

They are slow by today's standards Two solutions for Gene Wright's addition test are

Sinclair Cambridge Programmable
Count: 355
Code: rcl + 1 = sto gto 00

Sinclair Cambridge Proigrammable
Count: 384
Code: + 1 gto 00


Hi Palmer,

Thanks for the tip about the battery. I think you're thinking of the Cambridge Scientific Programmable which took a 9V battery. I had one of those, but gave it away :-) The one I actually have now is the Cambridge Scientific (non-programmable), and it's powered by 2 x AA batteries, but taking your advice, I'll make sure they are fresh.

BTW, I have total respect for Clive, and his ideas, just sometimes the implementations lacked the quality they deserve - shame really.


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