ZX81 ULA

Discussions about Sinclair ZX80 and ZX81 Hardware
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Zx81BASIC+
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Joined: Tue Mar 30, 2021 9:27 am

ZX81 ULA

Post by Zx81BASIC+ »

Hi. I’ve had a great response from my first post (ZX81 black screen), so thanks to all that took the time. This leads me to my next question : replacement ULA’s ? Are they the proverbial rocking horse poo ? Or is it possible to find one ? My online searches have been quite disappointing. Thanks in advance.
patters
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Re: ZX81 ULA

Post by patters »

Aren't they a similar price to the real "new old stock" ULAs currently on eBay though (possibly from ZX81 kits that were never built)? This thread should probably be in the hardware subforum.
Lardo Boffin
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Re: ZX81 ULA

Post by Lardo Boffin »

There is the vLA81 when available. Other than that it is luck of the draw on eBay for one.

You could of course buy an untested zeddy pretty cheaply and borrow the ULA but then you have another one to do something with...

But the golden rule is that no zeddies get harmed!
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Moggy
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Re: ZX81 ULA

Post by Moggy »

Says the man who lights them with fire and hits them with sticks!! :lol:

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1024MAK
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Re: ZX81 ULA

Post by 1024MAK »

I’ve moved this topic to the hardware section.

Although there have been various ULA replacement designs and modules, currently we only know of one that is currently being made. That is the vLA81. See here for where to buy one.

But keep in mind that both the COVID19 Corona virus outbreak and brexit are affecting shipping and deliveries :(
patters wrote: Fri Apr 02, 2021 10:53 am Aren't they a similar price to the real "new old stock" ULAs currently on eBay though (possibly from ZX81 kits that were never built)?
Actually some years ago (about five I think, could be a bit longer), a box of them (original ULA chips) was found in a warehouse, so for a few months there was a plentiful supply :D
But once that stock sold, that’s it for new unused ULAs. Unless someone decides to sell off their own spares.

It’s unlikely that any ULAs from unbuild kits will be sold separately, as the unbuilt kits are now considered ‘r@re’ and go for silly high prices on eBay.

Very occasionally, a used ULA may come up on eBay, or on Sell My Retro.

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