Sinclair Micromatic

[Johnbarn]

The recent death of Sir Clive Sinclair prompted me to look out my 1970 Micromatic, one of the tiny radios he designed and marketed in the late 1960's. I never had much success with it. It worked but never very well. Being a complex reflex circuit, it was prone to bursting into whistles and howls nomatter how I adjusted the reflex coil L3. The original leaflet explained that L3 can be bent over towards the aerial coil to improve sensitivity but with the risk of instability. How right they were! Eventually this coil fractured due to me trying to better the reception by more twiddling and it was put away for over 40 years. I found it again a few days ago in a sorry state at the back of a drawer. At some time in the past one of the button cells had leaked and eaten away parts of the adjacent track but I managed to bridge the affected tracks with 5 amp fuse wire. The reflex coil L3 was more difficult and I had to sacrifice a couple of turns and make new connections to the remaining wires. Eventually I got it to work, albeit with the same howls and whistles as I remember forty years ago but Five Live came in loud and clear although hand capacity was a bit of a problem - not helped by the attractive brushed aluminium front plate. And the frequenct markings on the dial are at best speculative. However the circuit is amazing with the two Si npn transistors being used for both RF and AF amplification. It is still very tempramental but I am resisting the temptation to twiddle at the adjustment of L3. I will keep it as it is and accept that it is a relic of auld decency which may never be perfect but was the first radio I ever built. Thank you Sir Clive.

[Johnbarn]

Photos of the Sinclair Micromatic.

[Sideband]

I had the earlier Micro 6 which worked reasonably well and had three transistors I think. The biggest problem with mine I seem to remember the tuning knob kept detaching from the screw that adjusted the pre-set trimmer. Don't know what happened to it. I later had the Micro FM which sounded amazing when connected to an external amplifier. The problem with that was you couldn't get PP5's easily.

RIP Sir Clive, A lot of your products might have been a bit flakey in operation but they encouraged a lot of people.

[Mr 1936]

In 1965 when I was 12 and my brother was 8, we subscribed to "Practical Wireless" and eagerly awaited each issue. Crystal sets with transistor AF amplifiers were the order of the day, with later forays into reflex circuits.

The picture shows the cover of the November 1958 issue (a few years before we got going) showing an 18 year old Clive Sinclair only just out of school. He seemed to be always a few years ahead in thinking, and was the pioneer of transistor radios when industry was tentatively changing over but home constructors were happier with the valves they knew and loved.

As his products were introduced over the years we saved up for and sampled quite a few of them between us, with the joy and frustration they brought in equal measure !

[peter_scott]

His products were iffy. I only ever bought one, the Sinclair Micro FM. I built it as per instructions but placing your hand anywhere near the thing caused it to offset the tuning which made station selection rather tricky to say the least.

Peter

[Andrew2]

I had the earlier 3-transistor version of the Micromatic and it was fine, but like all regenerative sets it became very frisky if you advanced the feedback too far in an effort to hear the weaker signals. Having said that, it was possible to hear Caroline North here in east Manchester without difficulty, and it wasn't a strong signal by any means. Even my brother's 6 transistor superhet struggled! My mate had the later 2-transistor one like yours and AFAIR it too was fine. I wonder what is making yours so fussy?

[Craig Sawyers]

I bought two of his P50 power amps and the PZ8 regulated power supply. The power supply blew up within minutes.

In fairness, there was no quibble - they just replaced it.
But looking at the prices, that little lot would have cost the 15 year old me £15. Without the cost of a cast to put it in.

That was not cheap - around £230 in today's money, plus a box. Plus the preamp I built from scratch. So call the project £450 in today's money.

Deviating somewhat:

But in fairness everything was expensive then. Superhet transistor radio kits were £8.50 (£130), and an Armstrong 521 amp the equivalent of £700 today!

I actually have two of these in the loft; and measurements suggest performance is decidedly "iffy" by today's audio standards. Germanium output transistors no less.

For the same sort of money you can now by a Quad Vena II, which has pretty spectacular performance https://www.richersounds.com/quad-ve...ster-grey.html .

And there are many amps a whole lot cheaper than that.

So was Sinclair audio (and radio) gear expensive? Yes. And as we know, not too reliable. But as we also know, he was often ahead of the curve.

Craig

[cheerfulcharlie]

Well, that is a revelation as I always thought they were all FM.

In that case, there didn't seem much point to them as you could build a crystal set at a 10th of the price with the then very abundant crystal earpiece and not need any batteries.

They looked very nice though and sometimes could be seen as a prop for a much more exotic piece of equipment on TV shows etc.

as you could build a crystal set at a 10th of the price with the then very abundant crystal earpiece and not need any batteries.

Hardly portable though.

[Richard_FM]

Originally Posted by cheerfulcharlie

Well, that is a revelation as I always thought they were all FM.

In that case, there didn't seem much point to them as you could build a crystal set at a 10th of the price with the then very abundant crystal earpiece and not need any batteries.

They looked very nice though and sometimes could be seen as a prop for a much more exotic piece of equipment on TV shows etc.

I think in an episode of The Saint one is used as a walkie talkie.

[60 oldjohn]

This is my Micromatic, I've never heard a peep out of it

And a picture of my Sinclair Slimline

John.

[dave walsh]

Well I never knew that was Clive S on the cover of PW [post4*] The adjusted for inflation product prices for everything [p7* often quoted] are accurate but at the same time, misleading. Twenty years ago, I was amazed to discover people in Sussex paying out £20 for fish and chips. We were beside the sea but the fish came from Norway. At one point such a meal or a pint of beer was totally affordable for anyone, unless you were really, really out of funds! Then it became a relative luxury. Sinclair products and some others in PW were [relatively] very expensive and [for me] too small and limited compared with what value you could get from buying surplus gear [if you could afford that]. Trendy items ie micro radio's aside though... products like the Z12 amp were a revelation and affordable . Mine didn't work but advice from Cambridge quickly sorted that. It was one side of my cheapo "Quad" 4 channel system created from largely scrapped components including two car speakers for the rear output. channels [nothing to do with the short lived Sony Quadrophonic product]. I just wired them in series from + on the left to + on the right as per Wireless World info. The other stereo side was my tape recorder's built in amp. Using an SP25 deck with a stereo cartridge and the right sort of LP [ie Surfs Up The Beach Boys] it sounded pretty good.

Dave W

[Graham G3ZVT]

Originally Posted by dave walsh

Trendy items ie micro radio's aside though...

There might have been more of that than we imagine.
My wife and I were asked to "house sit" for another much older couple while they went on holiday, I brought along my ZX81 to pass the time, but I noticed they had their own, kept on display in a bookcase. The couple were absolute technophobes and I can't imagine they ever switched it on, but I suppose it showed that even they realised, that unassuming black plastic wedge symbolised a revolution.

[mark pirate]

As his products were introduced over the years we saved up for and sampled quite a few of them between us, with the joy and frustration they brought in equal measure !

I have a couple of Sinclair mini TV's both are still working fine, I also just sold my Sinclair Zike, it was a very flimsy thing, and a sales flop, but as most Sinclair products were, it was ahead of its time.

I still own an original C5, again, a sales flop, but a very clever bit of thinking.
I wonder if the passing of Mr Sinclair will increase the prices of his many innovative products?


Mark

[cheerfulcharlie]

Originally Posted by Richard_FM

I think in an episode of The Saint one is used as a walkie talkie.

Ah yes, thought it would be one of those adventure series' that we took for granted then.

I recall buying one of those Hong Kong or Japan? crystal set kits for about 5 shillings,(two weeks pocket money) it worked well for free electric LOL.

Not sure why Sir Clive thought the public would tolerate obscure batteries.

[slidertogrid]

My Uncle bought me a Micromatic kit for Christmas I didn't realise at the time what an expensive present it was! I built it and it worked ok as far as I can remember but I also had the problem of the tuning knob becoming loose. I don't think it lived past its first set of batteries as I can't remember buying any replacements...
I went to tech collage with a chap who worked for Sinclair, he could buy the first generation of the micro TV set (the multi standard one) cheap with discount for staff. I think they were expensive retail. I cannot remember what he was flogging them for. Then came the later UK only version around 1978 I think, they were cheaper but nastier he got a lot that were returns we fixed them in our practical class. It seems that any faulty returns were just scrapped which seems odd for a small firm.
A local chap had a C5 he was often seen trundling through Bretton in Peterborough, the road through Bretton is single carriageway 40 MPH. How he wasn't flattened by a Sainsbury's lorry I don't know! Maybe with the current fuel shortage problems the value of a C5 will go up? I suppose with lighter more powerful modern batteries available now they could be practical at last?
RIP Sir Clive!

[bluepilot]

I used to live near the Sinclair factory in St. Ives and knew several people who worked there. A friend of mine had a job working from home mending micromatics. People would buy a micromatic kit, assemble it wrongly and then send it in to be repaired. Sometimes the mistake was easy to correct and sometimes not so obvious. He had been provided with a good stock of kits and was told that if the mistake was too difficult to correct he should just build another one and throw the original away. There was no check on whether he mended one or threw it away so he was always good for a cheap micromatic kit if you needed one

Another friend mended Z30s and Z50s. There were several discos in the area powered by "surplus" Sinclair amplifiers.

[ajs37]

I had a Micromatic kit - they were very well marketed for the 70's, but they didn't live up to expectation! Mine worked ok as long as you didn't fiddle with it too much! The case was made from brittle plastic and fell apart after a couple of years
I also had 2 x Z50s, PZ6, and the stereo 60 preamp in a box - in fact I still have it - I used the amp for a long time and was quite happy with it - we didn't have much spare cash at the time, so all my hifi stuff was made from kits - Sugden BD1, SAU2, Shure M3D, Neslon Jones tuner, Linsley Hood cassette deck (Hart Elec), WW Dolby kit from Integrex - speakers made up from flat panel polystyrene units (actually they were good).
I still have everything apart from the speakers!
Now I use Quad 303 with a Quad Vena and a mixture of other gear - still have another Quad 303/33/FM3 kit that I need to offload! They will appear on the forum at some stage...
Cheers
Andy

[Richard_FM]

The early Microvisions had some Ni-Cad batteries soldered to a circuit board, which have often over time leaked & caused internal damage.

The later ones had a separate battery holder, I'm not sure if they had the circuitry to recharge batteries.

[suebutcher]

The Micromatic is a classic example of a Sinclair product; Iain Sinclair's snazzy minimalist styling makes you want to buy this thing from the future, and also makes you forgive its failings afterwards. The same goes for the Project 60 and Project 80.