Sinclair ZX80 / ZX81 / Z88 Forums

HC and HCT are essentially interchangeable. There is no internal difference... They are interchangeable from logic function but have not (definetely not !) internal design and not same data characteristic. Do you ever read datasheets? Certainly! :-) The data sheets are different, but the parts are ...

Well, I am not planning to develop a new board, I already finished development... This is not really a community project with democratic decisions... I just do the board as described for myself... this will go in production... I won't do any design changes at all. ;) Thanks PokeMon; I understand yo...

I don't think it's healthy to pitch this as competition - however casually ;) I agree. It would be silly of us to make the same board. It would add nothing to the community, and there would be no advantage to buying one or the other. Sales of each board would be cut in half, meaning that both of us...

... I heard about the board you did maybe 2 years ago and Paul showed it to me on the last ZX team meeting in April 2013. So my approach is a little bit different... I want to keep most like original. Even should look a little bit nice, not the standard green IT stuff you get saturated after some t...

Very nice, Pokemon! It sounds like it will be a very distinctive board with the white soldermask and black silkscreening. I am working on exactly the same project, so perhaps we can collaborate. I am making a rev.B version of the ZX80 board I produced a couple years ago. Have you perhaps looked at i...

Hello to all, I apologize for the long pause! KnightFire "woke me up" with a private email to see how things were going on my ZX80 board. The rev.A boards worked, but had a few problems I wanted to resolve before ordering more (keyboard layout, shift key operation, and video output). I set it aside ...

Good timing on this, zx80nut! I have fixed all 40 of the key locations on my ZX80 clone board to match the original. The layout is tricky, but it will work with either the overlay (identical to the stock ZX80), or 40 individual keyboard switches (more reliable and easier to use). I was still not cer...

The ZX80 keyboard membrane arrived from Paul. Thank you for sending it! I matched it up to my revised ZX80 layout, and it fits. The only thing I'll need to change are the outer edges. (assuming that there are supposed to line up with the PCB edges). BTW, it really does look great, RWAP! Thank you so...

Just in case you are (still) interested, Lee. I have a ZX80 keyboard membrane from Rich at home and would sponsor it to you. Just send a PM or an Email to me with your adress if you want me to send it to you. As these are the only membranes available at this time it would be our only chance. CU Pau...

Hi Users! I found this while surfing the Web: http://microwave.gr/giannopk/zxcomputer/PCB_Foils.pdf Maybe this will help a bit :-) Jens Yes, I used this to guess at the board size. Knowing that the IC pins are on 0.1" centers, I scaled the length and width accordingly. Grant's PCB drawing shows 15....