Search found 7 matches
- Mon Dec 24, 2018 6:24 pm
- Forum: SALES
- Topic: A Gaggle of ZX81's for sale
- Replies: 8
- Views: 7716
Re: A Gaggle of ZX81's for sale
No power or accessories--tough sell. Somebody had aspirations of distributed-computing something or other, but with today's Arduino and Fruit Pi platforms, there are better ways. It would be nice to refurbish them all and sell them one-by-one, but collectors want the full package. Being on the Amer...
- Sat Jul 21, 2018 5:26 am
- Forum: Hardware
- Topic: Yet another repair
- Replies: 18
- Views: 7541
Re: Yet another repair
A bit of an update... I had some things get in the way and I never got time to come back to this. I haven't gotten a replacement ULA yet, I really want to, but budgeting is getting in the way. I cleaned it up a little and got the screw posts glue-welded back together (they had broken off). I found a...
Re: ZX81 ULA
I was just looking for a replacement and it went by too fast. They are not overly expensive also!
- Thu Jun 28, 2018 6:16 pm
- Forum: Hardware
- Topic: Yet another repair
- Replies: 18
- Views: 7541
Re: Yet another repair
If the ULA is in a socket, the quickest way to fault find, is to swap it with a known good working ULA. Of course, this only helps if you have another one... Mark That part where you suggest to swap another ULA. About that, where do you even find another ULA, it's a custom chip. The CPU is not doin...
- Thu Jun 28, 2018 5:46 am
- Forum: Hardware
- Topic: Yet another repair
- Replies: 18
- Views: 7541
Re: Yet another repair
Hey Floopy. Welcome :-) Greetings Jens Thank you, I went back to measure and I can confirm that the pin 35 on the ULA is always high. 4.2V to be exact, no oscillation. I'm not very familiar with this kind of setup, does the ULA have to work to be able to create a clock? The current consumption is a...
- Wed Jun 27, 2018 4:44 pm
- Forum: Hardware
- Topic: Yet another repair
- Replies: 18
- Views: 7541
Re: Yet another repair
Tha's what I was thinking at first. I'll try to measure again tonight and see what I come up with.
- Wed Jun 27, 2018 4:19 pm
- Forum: Hardware
- Topic: Yet another repair
- Replies: 18
- Views: 7541
Yet another repair
Hello, my name is Floopy. I'm brand new here, but I've been playing with old hardware for quit some time. I was recently given a TS1000. I hate the keyboard, but the computer is restoration worthy. Anyway, when I power it up all I get is a black screen and occasionally a brief white line. My first s...