"Different" ZX81's

[1024MAK]

got some odd expansion modules too it there a thread for unusual expansions ?

Not a recent thread about different unusual expansions that I can think of, so why not start it

I would be interested, and I'm sure others here would also be interested

Mark

[Fwapp]

Definitely - always good to see some pluggy-in-things

[gozzo]

not really normal but used when they couldnt get enough mask roms, the 64k means 64k bits, or in normal terms 8k byte, this is how eproms were normally coded, 2564=64k bit, 8k byte...

[1024MAK]

not really normal but used when they couldnt get enough mask roms, the 64k means 64k bits, or in normal terms 8k byte, this is how eproms were normally coded, 2564=64k bit, 8k byte...

And 64k bits sounds better than 8k bytes

Besides, a byte was/is not always 8 bits...

Mark

[Lardo Boffin]

Here is the issue 3 Timex 1000 that arrived today from Greece:-

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IMG_5544.JPG

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It has an older ULA 2C184E and produces a very dark output. The date stamp on the this and the Z80 are very close so it may be original?

As soon as a ZX8-CCB comes up for sale it will produce a nice output!

[Fwapp]

Interesting that, back on page 6 I posted a pic of ULA's with 8221 (2c184) and 8222 (2c210) datecodes, the same and close to the datecode of yours. But they are in Issue 1 pcb's. Looks like Timex were using issue 3 pcbs before the UK.

[Moggy]

Interesting that, back on page 6 I posted a pic of ULA's with 8221 (2c184) and 8222 (2c210) datecodes, the same and close to the datecode of yours. But they are in Issue 1 pcb's. Looks like Timex were using issue 3 pcbs before the UK.

I would agree with that Fwapp the zeddy was introduced in the States in 82 and as far as I'm aware always had the "nice" green then red issue three board which I don't recall getting over here till 83.
The last issues of the zeddy also came with the heavily slimmed down third reprint manual.
(162 pages as opposed to 200+)

@Lardo

Nice little tooter Lardo and with a genuine Zilog motor too!
Keep us up to date with this one please.

[Lardo Boffin]

@Lardo

Nice little tooter Lardo and with a genuine Zilog motor too!
Keep us up to date with this one please.

I have borrowed the 210 ULA out of my sparkly pixel zeddy and checked it in this one. It now produces a pretty reasonable picture:-

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There is slightly more picture noise with the ZXPand plugged in but no sparkle which is a relief.

I still have not figured out the fine tuning on my stupid telly - it finds a near perfect picture and then seems to decide this one is best to store!

Fingers crossed a ZX8-CCB and maybe new regulator and I will have a lovely working TS1000.

[Moggy]

Hells teeth!
If the picture from the modulator looks that good then composite will look great.
With a nice switching reg to keep things cool and one of Pokemons' tiny boards that zeddy will be a little beauty .

Great to see someone enjoying their modding.

[Fwapp]

Moggy's right - that's a cracker of a picture!

You be careful though, Lardo, 6 months from now, you'll open a cupboard and wonder why you have so many ZX81's!

It does get addictive