ZX81s with the ROM fix

Discussions about Sinclair ZX80 and ZX81 Hardware
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Whopper
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Joined: Mon Jan 22, 2018 8:38 pm

ZX81s with the ROM fix

Post by Whopper »

So, I've just received another ZX81 fro eBay. Opened it up and it's another one with the ROM fix chips on top.

I only have three ZX81s, two being with the ROM fix, so exactly HOW rare are these things?

Whopper
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1024MAK
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Re: ZX81s with the ROM fix

Post by 1024MAK »

Apparently in your house, not rare at all... :lol:

Different story here, I have at least ten ZX81s with normal ROM chips... plus I think one with the extra circuit to fix the ROM.
Of those without the fix, one is not working due to a faulty ULA. This may have the bugged ROM. I think most of the rest have the 'fixed' ROM.

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Lardo Boffin
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Re: ZX81s with the ROM fix

Post by Lardo Boffin »

I have bought three kludge fix zeddies (i.e. with the extra circuit on top) off eBay so far. But then that is probably out of 15 to 20 zeddies.
I think I passed two of these on to members on here. :)
They tend to have the deeper sponge feet rather than the shallower harder rubber feet and in my case two of them came with ZX80 PSUs.
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TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
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