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Timex Sinclair 1000 repair

Started by JKnightandKARR, Jan 02, 2026, 01:44 PM

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Chris Savage

Quote from: JKnightandKARR on Jan 12, 2026, 09:58 PMOne i know of was ZX81 +38 or something like that

I was going to order this one, but as you can see, shipping to the U.S. starts at $50.00!!!

                    Bringing concepts to life through engineering.

JKnightandKARR

Quote from: Chris Savage on Jan 12, 2026, 10:52 PM
Quote from: JKnightandKARR on Jan 12, 2026, 09:58 PMOne i know of was ZX81 +38 or something like that

I was going to order this one, but as you can see, shipping to the U.S. starts at $50.00!!!
Order that with the sockets for the chips! Only an additional $50.... lol kinda $$$$$$ can buy an original for 1/4 cost

JKnightandKARR

#32
Quote from: Chris Savage on Jan 12, 2026, 10:52 PM
Quote from: JKnightandKARR on Jan 12, 2026, 09:58 PMOne i know of was ZX81 +38 or something like that

I was going to order this one, but as you can see, shipping to the U.S. starts at $50.00!!!
https://github.com/mahjongg2
I found this, idk if this looks interesting to you or not, beats $250... lol

Edit: Here's what looks like original PCB of the ZX-81
https://github.com/Bluescreen2001/ZX81-PCB/tree/main/ZX81_keyboard

granz

Quote from: Chris Savage on Jan 12, 2026, 04:44 PM
Quote from: granz on Jan 12, 2026, 03:55 PMAlso, related to this: Brian (AKA @MicroNut) has (had?) a ZX-81 remake.

Define: remake?
A modern remake of the old ZX-81. There are several (one of them is here: https://www.hackup.net/2022/01/building-a-new-zx81-computer/.) I don't remember which one Brian had, as that show was many years ago. That is why I tagged Brian, I was hoping that he could pitch in.

Chris Savage

Quote from: JKnightandKARR on Jan 12, 2026, 11:51 PMOrder that with the sockets for the chips! Only an additional $50.... lol kinda $$$$$$ can buy an original for 1/4 cost

Yeah, I did think the $50.00 for extra sockets was a bit much. Of course, the modernized versions don't require an old TV to get video.

                    Bringing concepts to life through engineering.

Chris Savage

Quote from: granz on Jan 13, 2026, 06:57 AMA modern remake of the old ZX-81. There are several (one of them is here:

I don't think tagging works on SMF.  :-\  That PCB looks like the one JKnightandKARR linked. Mahjongg?

                    Bringing concepts to life through engineering.

MicroNut

#36
The remake that Granz was mentioning that I had was a DE0-Nano FPGA board with a ZX81 softcore called ZXGate I found on the internet. The "cassette" was an Arduino Due which had a TFT screen and a SD card reader. Sadly I lost the code for the Arduino but I also made a "cassette" with a Propeller 1, SD card reader and a serial 16x2 LCD. I no longer have that code either. :(

The cassette remake is just reading an SD card and then bit banging pulses based on each bit of each byte. Once the timing is determined and using a 3.3V output you can feed it into the "mic" jack. It wouldn't be too hard to replicate it again and I found that it is more reliable than the actual cassette system.

I also have 2 TS1000s, a US ZX81 and the ZXMore kit (can also do ZX80) that is no longer available.
Always looking to the stars.

granz

#37
Thanks Brian, I was pretty sure (>99%) that you had a TS-1000 clone, but I forgot that it was an FPGA system. I also think that I have a DE-0 system somewhere, that I inherited when Peter moved out.

By the way - did you get an email alert from my tagging you, or did you just happen to log in and see the posts?

JKnightandKARR

Quote from: Chris Savage on Jan 13, 2026, 10:22 AM
Quote from: JKnightandKARR on Jan 12, 2026, 11:51 PMOrder that with the sockets for the chips! Only an additional $50.... lol kinda $$$$$$ can buy an original for 1/4 cost

Yeah, I did think the $50.00 for extra sockets was a bit much. Of course, the modernized versions don't require an old TV to get video.
Just alittle bit... lol

Quote from: MicroNut on Jan 13, 2026, 03:15 PMThe remake that Granz was mentioning that I had was a DE0-Nano FPGA board with a ZX81 softcore called ZXGate I found on the internet. The "cassette" was an Arduino Due which had a TFT screen and a SD card reader. Sadly I lost the code for the Arduino but I also made a "cassette" with a Propeller 1, SD card reader and a serial 16x2 LCD. I no longer have that code either. :(

The cassette remake is just reading an SD card and then bit banging pulses based on each bit of each byte. Once the timing is determined and using a 3.3V output you can feed it into the "mic" jack. It wouldn't be too hard to replicate it again and I found that it is more reliable than the actual cassette system.

I also have 2 TS1000s, a US ZX81 and the ZXMore kit (can also do ZX80) that is no longer available.
That'd be VERY handy! I'd like one if one can be recreated.

Quote from: Chris Savage on Jan 13, 2026, 10:25 AM
Quote from: granz on Jan 13, 2026, 06:57 AMA modern remake of the old ZX-81. There are several (one of them is here:

I don't think tagging works on SMF.  :-\  That PCB looks like the one JKnightandKARR linked. Mahjongg?
Did you see the files I posted? I think original PCB designs, as well as new designs as you already saw,  for the ZX=81 or Timex Sinclair 1000, seem that the 2 systems, even though technically the same, are somewhat different, at least as far as the RF boxes are concerned.

MicroNut

Granz, no I didn't see the alert.

JKKnightandCARR - sadly I lost all my ZX81 FPGA and Cassette source code when the external hard drive I had it on went bad. I do have the ZX-gate source though which is good since it is no longer on the net.

I'm thinking of redoing it. I know the ZX-Gate used a PS2 Keyboard and VGA output. When I used the DE0-Nano I tapped into the video output before the vga conversion and had to use a transistor driver to get the composite output. I now have a DE10-Lite which has a built in VGA and Arduino header with double the space of the Nano so I will do it on that instead. Once that is done it'll be easy to port it over to the Nano

I'll start a thread on the Projects category when I get it going so I won't hijack this thread.
Always looking to the stars.

Chris Savage

#40
Quote from: MicroNut on Jan 13, 2026, 11:00 PMGranz, no I didn't see the alert.

I've looked into mods for SMF that can do this, but the few I see don't look like they've been updated in years.

EDIT: Ironically, the manual says they're supported. I need to check on permissions. I will look into this now.

                    Bringing concepts to life through engineering.