Sir Clive Sinclair

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That is asking for 6 significant figures - so you are/were not comparing like-for-like.

The Sinclair had only a 4 figure mantissa so the best you would ever get would be 5 figures (It did hold another digit in memory so the last one displayed would be accurate). The HP-35 had 10 significant figures but of course cost nearly 3½ times as much.

My needs at that time were household & model-making so seldom greater than 2m.

It's interesting to realize today's cost equivalents --- Sinclair £566 - HP-35 £1905

I thought the Sinclair had 5 digit mantissa (unit plus 4 decimal places). Will have to dig mine out and check. - Edit: just realised mantissa is the part after the decimal point. So agreed, unit plus 4-digit mantissa.
I also have a Casio fx81 someone referred to. My parents bought it for me when I did maths A-level (which dates me). I never switched it off as it powers down after a few minutes of inactivity and the 2xAA batteries last years. (Unlike the Sinclair which could eat a set of AAAs in a single maths lesson).
I used it extensively for 15-20 years of my engineering career when Excel took over. A mate had the same calculator and soldered his power switch permanently on when it failed.
 
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So I thought I’d see if it stiil works ….
and it did
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I'd actually forgotten the QL - yes good but 'quirky' - tape drive ???

When I left a management post in the late 60's my staff bought me the Sinclair Scientific Calculator - just over £50's worth :(

Age and memory! The Scientific came out in 1974 - I was still at school and bought one - it was about 60 quid - a fortune in those days.

I still have it!! (and, yes, it still works) It's on my "shelf of horrors" along with my British Thornton slide rule, book of log tables and random other bits.

Further, I have his Quad ESL speakers plus the Quad 405-2 amp and the matching 44 pre-amp. All are in awful cosmetic condition - lots of nicotine (he was a heavy smoker), coffee cup rings, cat claw marks (speaker cloth ruined) etc.

I've designed and restored quite a few amps, including Quad 405-2s, e.g. Quad 405-2 upgrades , so these will be done as soon as I don't need PPE for something more critical!

Looking on the internet I have found a 1975 advert giving a kit price of £9.95 which is probably what I paid. About £85 in today’s money. Perhaps we are looking at different Sinclair scientific calculators if yours was £556 in today’s money.

The kit was originally around £28 but was significantly discounted within a couple of years to clear stock - Sinclair (and others) were producing progressively better and cheaper calculators - the market moved very quickly - and the kits had to go.

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I bought that Sinclair scientific as a kit. I remember covering a desk with cooking foil linked back to earth as antistatic precautions and soldering it together. It didn't work. I snt it back to Sinclair fearful I had done something wrong but sure I had soldered it right and taken every precaution. They sent me back a working calculator. Subsequently it became clear that very often Sinclair products were made from rejected batches of chips from the mainstream electronic industries.
 
Sinclair products were made from rejected batches of chips from the mainstream electronic industries.
Sometimes components can be 'rejected', but still work perfectly. They may be on the edge of test limits. Different companies set different tolerances. I worked for a company which got the very best of optical transceivers, so the ones we didn't want were sold to other customers. It is just part of normal manufacturing and still goes on today. Where problems occur is if the design doesn't account for the wider tolerances and if it's a kit, it won't have been tested as an assembly, so in that case you have good customer service to sort the problem. I think getting a working calculator in return is OK customer service, but must have been irritating.
Can you imagine what goes on today in far east manufacturing? all the 'rejected' parts will be sold and used by small manufacturers to build circuits which we all buy, but so cheap you get 10 and one always fails 🤣
 
When the calculators first appeared, pre April 73, they were probably classed as "luxury items" like cameras so attracted close to 50% purchase tax in those pre Vat days. Selling as a kit got round that (you could even buy a lotus 7 car as a kit). That might explain why kits were popular for things like calculators and stereo amplifiers. Plus only 3 TV channels so you had to find something to do on winter evenings.

I bet Sinclair abandoned kits soon after standard rate 10% vat arrived, customer support and returns must have been a nightmare. "yes sir, the components are guaranteed but you are supposed to solder with an iron, not a plumbers blow lamp....."
 
..."yes sir, the components are guaranteed but you are supposed to solder with an iron, not a plumbers blow lamp....."
I did once hear a story about a full computer kit (can't remember the brand) that was returned as not working. On inspection, the buyer had put all the components on the board perfectly, with the job being incredibly neat. Shame he'd used superglue instead of solder.
 
Anyone know of surviving descendants from Sinclair products? I never owned one. But had quite a lot to do with various Chris Curry products and businesses (post Acorn / BBC micro) Curry worked with and fell out & left Sinclair. Both made and lost lots. I think that Arm is a descendant of Curry activities... what is left of Sinclair’s
 
He was going to buy the Delorean factory to manufacture bigger electric cars but it all went wrong and Sinclair vehicles liquidated a few months later. Always wanted a c5, i like the unusual, I have the Delorean 😀
 
If you have a proper original DeLorean you owe us about £6000 each. Tax subsidy divided by the number made. 😁. I know he got off the drug trafficing charges, but have you checked the trunk for white powder?

(only having a go because I'm slightly envious of anyone with an interesting car.)
 
If you have a proper original DeLorean you owe us about £6000 each. Tax subsidy divided by the number made. 😁. I know he got off the drug trafficing charges, but have you checked the trunk for white powder?

(only having a go because I'm slightly envious of anyone with an interesting car.)

Powder free.
 

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