Sinclair ZX80 / ZX81 / Z88 Forums

In my opinion the teaser is far to long considering the amount of information in it. Where is the website and what are the technical details? And what will it cost? Our plans are to make the repository public with all the technical information shortly. Basically what is missing is completing the do...

Captura de pantalla 2023-06-27 111751.png https://youtu.be/zVnGZ1Purzs https://codeberg.org/Retrostuff/SD81-Booster I open list to see possible interested people for a run of SD81 Booster The estimated price (assembled) is €50 55€ without case and €65 70€ with case + shipping and will be paid in ad...

https://lh3.googleusercontent.com/fMsghdn4A4FvM5DLhH1yiNbthjFbb72DT-V4Z-pJvvKkaQhYU8r2Lm8jG2mga5PyuKVmYqRN0aAIpaE78DJCIdk_YTYKOaw_Ucp8gMJC24z9YAfTCeOSzmQmUqPgeWl9ts0VKfFhMQ=w640 Hello guys! Some time ago I announced the next release of a Jupiter Ace clone that I am developing. The clone is currentl...

Hi guys! I just found a way to resolve an incompatibility in my zx80 clone design. :D The problem was that some models of 74LS00s used as IC11, inverts the video output. To fix it is necessary to insert a 47K resistor between pin 1 and pin 14 of IC 11 to make a pull-up in the pin 1. All the informat...

It is Eva rubber.
This type of material is sold in sheets in paper shops or craft stores.

Thanks

Paul wrote: ↑Thu Oct 26, 2017 5:47 pm But they don't burn 25 and 27 volt Eprom.

G540 can burn 25V EPROM.

I think it's not worth making an EPROM programmer. A new one for 8-bit EPROM is worth around € 30 on ebay.
I have this (G540):

But this other one I think still works better and cheaper (TL866CS):

They are wonderful. Are you thinking to get them for sale?

Good job. It has more chips - did you integrate the NMI generator ? So it is not a plain ZX80 ? ;) Not, it is something more, you can convert it in a zx81 with the selector in the bottom side. I think you will like the next pictures. ;) https://lh3.googleusercontent.com/C0irD_NNqt6NFz0AH4WDAwH8p2lR...