Surgery was a success! The ZX81 now has composite video! Shame most of the keys don’t work (probably the shitty ends on the connectors to be fair) but in all honesty I was planning on replacing it outright with a complete front patio remodelling if you know what I mean.

That and the 32K internal ram mod and first round of renovations is done!

@grimmware did it originally have RF out? Did you just take the video signal from before the high-frequency modulator, or was it more complicated than that?

@wolf480pl yes and yes :)

It was crazy simple, I just snipped the video and 5V in just inside the case for the modulator (okay, ended up doing video in just *outside* because the wire was jammed in between a resistor and a capacitor) and the video out from the output jack and wired all three into a TheFutureWas8Bit Atari 2600 composite mod, along with ground to the modulator casing.

Basically just followed this

Nice. My first computer was a Timex Sinclair 1000, which was pretty much the same machine as the ZX81. Man, did it ever run slower with the 16 kb RAM expansion cartridge...

@m3lang3 I’ve got one of those :) I’m going to do an internal 32K RAM mod and the see if I can use the edge connector as GPIO instead!

@grimmware As someone who's first machine was the US model (2k, not 1k, NTSC; all the rest is the same - save branding) I'm excited to see this (:

I still have mine, in storage, and... maybe one day I'll get it here and ... maybe by then I'll know z80 (:

@Truck @grimmware I’ve done the majority of the design work for the keyboard PCB so I just need to finish up and get it fabbed but I keep getting distracted by other projects!

@grimmware @grimmware send pix when complete, I'd like to send it to my dad, who bought me a keyboard for mine...

which never worked because ... it was for a mainframe, and the folks who sold it bilked him out of his money, which ... well he wanted to be supportive, and ... yeah.

anyway. would like to share if I can.

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