Search found 130 matches

by McKlaud
Sun May 20, 2018 1:52 pm
Forum: SALES
Topic: Unbuilt ZX81 up for adoption
Replies: 11
Views: 666

Re: Unbuilt ZX81 up for adoption

Fast!? I was away from this forum ... anyway your kit will be in good hands :)
by McKlaud
Sun May 20, 2018 12:26 pm
Forum: SALES
Topic: Unbuilt ZX81 up for adoption
Replies: 11
Views: 666

Re: Unbuilt ZX81 up for adoption

Damn it! :lol: I missed this one :(

Andy: could you do me favour and scan in hi-res both sides of the unsoldered PCB, please?
by McKlaud
Sat May 19, 2018 12:06 am
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 198
Views: 20613

Re: ZX81 ULA-in-a-CPLD

Yeah! It is possible, I did it my ULA, mapped 32K in 8K-40K area. It works in principles but have not tested extensively.
by McKlaud
Thu May 17, 2018 10:54 pm
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 198
Views: 20613

Re: ZX81 ULA-in-a-CPLD

Image
by McKlaud
Wed May 16, 2018 10:04 pm
Forum: Development
Topic: ZX81 ULA-in-a-CPLD
Replies: 198
Views: 20613

Re: ZX81 ULA-in-a-CPLD

I am impressed with your progress, Andy. Well done and the board looks stunning. :geek: :geek:
by McKlaud
Mon May 14, 2018 12:28 am
Forum: Hardware
Topic: 28C64 in 2364 socket (28 pin to 26 pin)
Replies: 10
Views: 621

Re: 28C64 in 2364 socket (28 pin to 26 pin)

Hi Martin,

Have you managed to squeeze your board inside the Zeddy case? I went to the SMD route and still the board a bit too fhigh. I should buy some flip-pins and try them.

Image
by McKlaud
Fri May 11, 2018 10:12 pm
Forum: Hardware
Topic: zx spectrum in zx81 case
Replies: 63
Views: 6691

Re: zx spectrum in zx81 case

Do you have an oscilloscope? If so, check 14MHz (74HC004 - pin8) & 3.5MHz (Z80 clock - pin 6) signals on the board and also the Csyns signal on to pin 8 of miniDIN8 socket.

If you touch with a finger the bottom of your board near the 74HCU04 is anything changing on the screen?
by McKlaud
Sun May 06, 2018 7:52 pm
Forum: Development
Topic: ZX Printer Belt
Replies: 102
Views: 8880

Re: ZX Printer Belt

Mark, much appreciated. Anything (any parts) for ZX Printer are welcome.
by McKlaud
Sun May 06, 2018 5:05 pm
Forum: Development
Topic: ZX Printer Belt
Replies: 102
Views: 8880

Re: ZX Printer Belt

They look great! Unfortunately my ZX Printer has got a cooked ULA and no replacement available :(
by McKlaud
Sat May 05, 2018 12:17 am
Forum: Hardware
Topic: zx spectrum in zx81 case
Replies: 63
Views: 6691

Re: zx spectrum in zx81 case

I did not say that was anything wrong with the crystal. The type of the 7404 inverter is critical. You should try to install there 74HCU04 instead of either HCT or HC.