Search found 7 matches
- Sat Oct 05, 2024 2:50 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
Re: ZX81 with mismatched ROM, jumper cable and flat cursor
It lives! The new keyboard arrived, fitted, and all keys worked first time - the old keyboard goo wasn't that hard to get rid of in my case, guess I was lucky or somebody had replaced it previously? Whilst tinkering, I also fitted a ZX-WESPI (minimal version), replaced the regulator and created a US...
- Tue Oct 01, 2024 5:41 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
Re: ZX81 with mismatched ROM, jumper cable and flat cursor
Thanks again both, yes getting there! I connected various pins from one connector to the other and as if by magic, text appears! Knowing the keyboard or cable at least is bad, I thought I might as well cut the scrappy ends off the cable and give it a go. I did once get a couple of numbers, but nothi...
- Mon Sep 30, 2024 11:41 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
Re: ZX81 with mismatched ROM, jumper cable and flat cursor
Success! zx81DisplayFixed.jpg And this is what it looks like now! :shock: zx81BottomFixed.jpg So on to the next challenge, the keyboard doesn't do anything. I couldn't immediately find any, but are there any guides on diagnosing keyboard issues? The connector cables look like they have been bent qui...
- Mon Sep 30, 2024 9:11 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
Re: ZX81 with mismatched ROM, jumper cable and flat cursor
Fantastic, thanks for both of those, much better than the reference images I found. Now down to work...
- Mon Sep 30, 2024 6:47 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
Re: ZX81 with mismatched ROM, jumper cable and flat cursor
After a bit more of an inspection, I found my board has a section of missing links which probably won't help:
So I'll work on figuring out where the ends should be and add them back in and check the connectivity of the rest...- Sun Sep 29, 2024 11:03 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
Re: ZX81 with mismatched ROM, jumper cable and flat cursor
Thanks for the info! I've carefully removed the ROM fixer board, and plugged the Z80 back in, but the screen looks exactly (pixel by pixel) the same. So based on what you said about broken tracks, I removed the ULA too, however when I pulled the chip out, the metal contact from the socket for pin 31...
- Sun Sep 29, 2024 3:46 pm
- Forum: Hardware
- Topic: ZX81 with mismatched ROM, jumper cable and flat cursor
- Replies: 16
- Views: 4851
ZX81 with mismatched ROM, jumper cable and flat cursor
HI! I've just picked up my first ZX81 from ebay and unfortunately can't get a readable prompt. The board has already been modified with a composite board, but it also seems to have a couple of other mods: It's an issue 1 board with the ROM fix standoff board, but the ROM chip appears to be a later 6...