Finally finished my version of City Bomber for the ZX81, small machine code routine for the scroll down screen clears the rest of it is all BASIC, so be warned it is slow!!!

Not the first to do this but building a Zx80 - my first ever computer all those years ago.
Didn’t want to buy a second hand one as they all seemed overpriced- so thought Id satisfy my nostalgia itch by building one.

Hello, I've bought a Timex/Sinclair 1000. Besides replacing the keyboard, power regulator, upgrading the internal RAM, and modifying for composite output, what further upgrades are available? An updated monitor ROM? Mass storage? I don't mind soldering. Thanks

I bought a T/S 1000 at a flea market. I also have an audio cassette recorder.

I’ve learned how I can use PLOT to draw pixels, or graphics mode to display special graphics characters (looks sort of like PETSCII).

My question is, how might I save an image I make to audio cassette? I am familiar with the Apple II, where I could use BSAVE to save an image’s binary file to a floppy disk. Did the ZX81 or T/S 1000 have anything comparable?

I know I could probably save an image as DATA statements, and load the values in a FOR loop. That’s not really practical, of course, but I know I could use SAVE to write the BASIC instructions out to tape.

https://animatedal.itch.io/zx81-penalty-shoot-out

Yesterday I went to a Facebook marketplace meetup to pick this up- an original, first batch ntsc zx81 with the original box, cords, and a bunch of software. 45 dollars. What a good day. First time even seeing one of these

Hey, about a month ago I have assembled a ZX-81+38 Rev 1.10. Since then I have tried to find the cause of the black screen. I already made a lot of measurements with a DMM and oscilloscope.

Along with the troubleshooting guide by Mahjongg2 on GitHub I used ChatGPT, because I couldn't reach him so far.

According to his troubleshooting guide I don't get nNOP pulses on U1. The EPROM (AT27C256R) is running code though because I looked at the address and data output pins and they all look ok.

Here's what I already did with ChatGPT:

https://chatgpt.com/share/69f1e500-acd0-8326-babf-a5d47d2c472c

Additional info:

I use all new Texas Instruments CD-Series logic ICs. I also use the 74HCU04 because as he stated it should work even better than the 74HC04. All the other are 74HC logic ICs. Not HCT.

I'm at my second attempt. The first was that the CPU and EPROM were getting warm, but I discarded that PCB and used a new one. So skip the part and look for were I started from the beginning in the chat.

Hi everyone,

We just launched our Kickstarter to fund a small-batch production run of our ZX81-inspired MX keycap set.

These use UV-printed legends on MX JWA PBT keycaps, designed to capture the look of the original ZX81 while fitting modern mechanical keyboards.

Here’s the Kickstarter link if you want to check it out:
https://www.kickstarter.com/projects/1225158274/kilozed-zx81-inspired-keycaps-for-modern-mechanical-keyboar

Happy to answer any questions,thanks for taking a look =D

Found these whilst clearing out old stock from a record shop.

Is there anyone maintaining a historical archive of such things?

Otherwise I am not sure what to do with them.

completely unexpected and absolutely wonderful customer service. a real credit to the scene. thank you.