Sinclair ZX80 / ZX81 / Z88 Forums

Hi. There are many people who have problems tuning in modern TVs to the old computers. What I have, and I recommend that you keep an eye out for on eBay (they do turn up now and again) is a Philips TV Tuner, model 7300. It was produced around the time of the Amiga, and was intended to display normal...

Hi. The original "mic" sockets on cassette recorders are designed to have a dynamic (moving coil) microphone plugged in. The output of these microphones was absolutely tiny, so the mic socket has a huge volume gain. As a result, to make the ZX computers (and others) compatible, the mic output is hea...

Hi Lee. The replica layouts on my page are very accurate (within a fraction of a mm) of the original board, so the centre of the keypad spirals (centred between the keypad contact through-holes) can to used to confirm the layout of the switches on your board from the edges. I've spend many (too many...

Hi. Just to let you know that I have just built a ZX80 using my re-drawn foil patterns to make sure the latest version was correct. I'm please to say it works, and also the cassette interface works. I also tested it using a normal ZX80 16K RAM pack plugged in to it. I've added details of the progres...

Hi. Just to let you know that I have now uploaded version 1.4 of my PCB layouts to my website at http://searle.hostei.com/grant/zx80/zx80.html [Edit by Grant on 7th July 2012 - UPDATED URL !] Using the photo of the PCB supplied by Rich (thanks !), I was able to reproduce the layout and the keyboard ...

Ah, thanks !

My x-ray vision was reasonably accurate then

I managed to get the right number of spirals. I'll tweak them to match the photo.

Regards.


Grant

Hi. I've been updating my ZX80 board design slightly as I have changed the pad contacts to be spirals instead of finger contacts (as I can just about see the spiral shape from the back of the board). Please see attached picture. I was wondering if anyone had ever noted / taken a picture of the PCB u...

Hi. Just to let you know that I have now uploaded version 1.3 of the PCB foils to my website. http://searle.hostei.com/grant/zx80/zx80.html [Edit by Grant on 7th July 2012 - UPDATED URL !] Regarding your replacement overlays, the replacement keyboards should fit on the old or the new PCB layout as t...

Hi. Regarding the board sizing: My "version 1.3" of the Issue 2 PCB foils has been updated to increase the size slightly to match the (corrected) actual size of 155.5mm x 204mm. This version will be released on my website shortly... http://home.micros.users.btopenworld.com/zx80/zx80.html The keyboar...

Hi. Just to let you know that version 1.3 of the "Issue 2" foils will be released soon. This fixes a couple of graphic tidy-ups, and the re-size (slightly!) to match the 155.5mm x 204mm of my real ZX80 board. I will release the latest version on my page shortly. For the foils, please refer to my pag...