HI.
Does anyone have any info / circuits for the Sinclair range of amps c1972.?
I think they were called the Z30 and Z50
Thanks
Andy
Does anyone have any info / circuits for the Sinclair range of amps c1972.?
I think they were called the Z30 and Z50
Thanks
Andy
I have three pages of the stereo 60 manual which gives a preamp cct, Z30 cct, and PSU cct. No transistor types though.
Do you want scans emailed to you?
Ross
Do you want scans emailed to you?
Ross
Andy,
I remember I have a little book, the "Sinclair Project 60"
that I have save from early 70`s.
And guess what, yes there was the schematic you serch for.
You can find it here:
http://web.telia.com/~u31641623/Sinclair Z30, Z50.jpg
--Bo
I remember I have a little book, the "Sinclair Project 60"
that I have save from early 70`s.
And guess what, yes there was the schematic you serch for.
You can find it here:
http://web.telia.com/~u31641623/Sinclair Z30, Z50.jpg
--Bo
HI.
Excellent.
Many thanks.
I built a version of this when I was at uni.
My first pcb.
2n3055 for outputs and BC109s [I think] NOT Sinclair specials.
It oscillated on one half cycle when fed with sine and blew up !!
When fixed, I remember it sounded pretty good and was more reliable than the Sinclair pre-built version I copied.
Andy
Excellent.
Many thanks.
I built a version of this when I was at uni.
My first pcb.
2n3055 for outputs and BC109s [I think] NOT Sinclair specials.
It oscillated on one half cycle when fed with sine and blew up !!
When fixed, I remember it sounded pretty good and was more reliable than the Sinclair pre-built version I copied.
Andy
Hi Ross,
Just opened up a treasure trove of electronic goodies packed in a box in my garage for the last 30years and found a complete sinclair project 60 set that I would like to rebuild.
I spotted your last thread of a few years back and wondered if you still had any of those schematics you talk about below.
If so I wondered if you would also be willing to e-mail them onto me at peter@bridgeconsultants.co.nz
Any help greatly appreciated.
Cheers
Peter
Just opened up a treasure trove of electronic goodies packed in a box in my garage for the last 30years and found a complete sinclair project 60 set that I would like to rebuild.
I spotted your last thread of a few years back and wondered if you still had any of those schematics you talk about below.
If so I wondered if you would also be willing to e-mail them onto me at peter@bridgeconsultants.co.nz
Any help greatly appreciated.
Cheers
Peter
I built many of the Sinclair systems for family and friends when I was a teenager in the 1970's. These included Project 60's (with the Linear Volume Pot!) and Project 80's (with the Coat Hanger Clip Pots).
I had a recurring problem with the power amp modules of the same vintage as the Project 80 - They were later ones than the Z30/Z50's, and may have been called Z40/Z60's. I seem to recall they used TIP42 output trannies. If left playing the whole day playing background music for merry housewives, the power amps would get warm, then get thermal runaway, then die, taking out the output trannies and the PSU fuse. This happened over and over again, despite very careful layout and grounding and reasonable heatsinking. I went through a sack of TIP42's
I did a brute force modification by replacing the output trannies with what we used to call Throffs (2N3055's) mounted on a huge heatsink, with the Z50 board tagged onto it. That seemed to do the trick.
I wrote to Sinclair about this and they replied with some embarrassment that there was a bias setting resistor for the output stage that was too low and they recommended I increase the value. 40 years on I can't remember the values (10 R to 15R??? it was about a 50% increase) but if someone posted a working link to a circuit of the Z40/60 it might jog my memory. Whether or not Sinclair later brought this mod to production I don't know.
Another Sinclair Wonder was the IC12 integrated 6W power amp. This worked quite well but was not short circuit proof. If the speaker leads were shorted it would die in a cloud of smoke and stink. I had a big sack of IC12 chips, too. I stand corrected, but I think the original Z30/Z50 amps may also not have been short circuit proof.
I had a recurring problem with the power amp modules of the same vintage as the Project 80 - They were later ones than the Z30/Z50's, and may have been called Z40/Z60's. I seem to recall they used TIP42 output trannies. If left playing the whole day playing background music for merry housewives, the power amps would get warm, then get thermal runaway, then die, taking out the output trannies and the PSU fuse. This happened over and over again, despite very careful layout and grounding and reasonable heatsinking. I went through a sack of TIP42's
I did a brute force modification by replacing the output trannies with what we used to call Throffs (2N3055's) mounted on a huge heatsink, with the Z50 board tagged onto it. That seemed to do the trick.
I wrote to Sinclair about this and they replied with some embarrassment that there was a bias setting resistor for the output stage that was too low and they recommended I increase the value. 40 years on I can't remember the values (10 R to 15R??? it was about a 50% increase) but if someone posted a working link to a circuit of the Z40/60 it might jog my memory. Whether or not Sinclair later brought this mod to production I don't know.
Another Sinclair Wonder was the IC12 integrated 6W power amp. This worked quite well but was not short circuit proof. If the speaker leads were shorted it would die in a cloud of smoke and stink. I had a big sack of IC12 chips, too. I stand corrected, but I think the original Z30/Z50 amps may also not have been short circuit proof.
I have a pdf of the Sinclair stereo 60 manual if anyone wants it. Ive already sent it to Peter.
As far as I know none of the Sinclair amps were short circuit proof. They were made to a very low budget and things like protection were ignored. Biassing of the output stages was a bit hit and miss, and they very often destroyed themselves.
Tony.
As far as I know none of the Sinclair amps were short circuit proof. They were made to a very low budget and things like protection were ignored. Biassing of the output stages was a bit hit and miss, and they very often destroyed themselves.
Tony.
I had bought the 40W power amplifier modules (well, at least they were supposed to be able to deliver a maximum sine power of 40W), and tried to use them at their maximum rated power.
As you can imagine, it all ended in smoke: the modules were very neat and cute with their TO126 output trannies, but they were BD189's, hopelessly under-dimensionned for that power...
I probably still have the full litterature somewhere, about the modules (Z80 I think), the project 60, techniques for bridging (sheer madness!).
I'll try to post the documents if i can get my hands on them.
As you can imagine, it all ended in smoke: the modules were very neat and cute with their TO126 output trannies, but they were BD189's, hopelessly under-dimensionned for that power...
I probably still have the full litterature somewhere, about the modules (Z80 I think), the project 60, techniques for bridging (sheer madness!).
I'll try to post the documents if i can get my hands on them.
Hello
Here is a quite complete web page about Sinclair audio products;
Planet Sinclair: Audio: Hi-Fi
Bye
Gaetan
Here is a quite complete web page about Sinclair audio products;
Planet Sinclair: Audio: Hi-Fi
Bye
Gaetan
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Not worth bothering with. There was no provision for setting the bias current so they had crossover distortion despite the claims for exceedingly small distortion numbers.
Well worth bothering with
They are a very interesting if not basic design
they can be a lesson to us all bias could be made adjustable !
emitter resistors can be added ! A great starting block
regards Trevor
They are a very interesting if not basic design
they can be a lesson to us all bias could be made adjustable !
emitter resistors can be added ! A great starting block
regards Trevor
Hi,
I too had some Sinclair kit until it blew up - as most of them ended up doing.
If you half the power ratings and set supply voltages accordingly
they may be more reliable but still nothing special.
Stan Curtis, hifi guru, Moth amplifier downloads are far better IMO.
😎 /Sreten.
I too had some Sinclair kit until it blew up - as most of them ended up doing.
If you half the power ratings and set supply voltages accordingly
they may be more reliable but still nothing special.
Stan Curtis, hifi guru, Moth amplifier downloads are far better IMO.
😎 /Sreten.
The Stan Curtis link is very interesting a class way above Sinclair in both performance and price
By the way is Mike from moth marketing still alive I used to know him but I have not seen him this last thirty years
regards Trevor
By the way is Mike from moth marketing still alive I used to know him but I have not seen him this last thirty years
regards Trevor
Here's a link to the Sinclair-System3000 schematic (not the best copy)
Categorized Schematics and Service Manuals for free download
Categorized Schematics and Service Manuals for free download
Wow, no thermal compensation in any of them. Was Sir Clive really too tight to add at least two diodes to the kit?
I seem to recall he often used reject transistors as well, that tested well enough for audio use. Of course, this is all way before my time - the only Sinclair thing I remember was the ZX Spectrum, and even then, by the time I got one they were being made by Amstrad!
I seem to recall he often used reject transistors as well, that tested well enough for audio use. Of course, this is all way before my time - the only Sinclair thing I remember was the ZX Spectrum, and even then, by the time I got one they were being made by Amstrad!
you certainly missed something...I had lots of Sinclair computing stuff...ZX81, Spectrum and QL...notorious unreliable, but great fun to toy with 🙂
regards
regards
Well i had my Spectrum until about age 14. Then I had what I consider to be the best computer I ever owned, where I learned most of my software engineering skills - the Amiga 🙂
I do know that Amstrad used to use the Sinclair developed amp-on-a-chip concept in many of it's stereo systems though.
I do know that Amstrad used to use the Sinclair developed amp-on-a-chip concept in many of it's stereo systems though.