ZX81 ULA wanted

ZX80 / ZX81 hardware and software requested for either sale or swapping
Ian13
Posts: 6
Joined: Thu Aug 03, 2017 5:42 pm

ZX81 ULA wanted

Post by Ian13 »

Before I decide what to do with my 'half dead' ZX81,(see my post in Hardware) does anyone know if there are currently 'any' responsibly priced ULA's available in the UK?

Thanks

Ian
Lardo Boffin
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Joined: Sat Nov 26, 2016 2:42 am

Re: ZX81 ULA wanted

Post by Lardo Boffin »

Hi Ian

Unlikely - I think most people end up having to buy a cheap donor zeddy on eBay.

There is talk of a new replacement ULA but nothing concrete as of yet. viewtopic.php?f=7&t=2110&start=80

Lardo
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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1024MAK
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Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: ZX81 ULA wanted

Post by 1024MAK »

Unless another box of them are found (very unlikely now), you will have a job finding a new old stock ULA for sale, let alone one for a reasonable price :(

See if you can find another ZX81/TS1000.

If you do get another machine, and it works, you can swap the ULAs over and see if the fault symptoms follow the ULA...

If do this and end up with a ZX81/TS1000 board without a working ULA and want to dispose of it, don't throw it away. Instead you can send it to me. I can make use of it.

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
Ian13
Posts: 6
Joined: Thu Aug 03, 2017 5:42 pm

Re: ZX81 ULA wanted

Post by Ian13 »

I was looking at the thread about a modern ULA thats drops in, sounds promising. Mine is not responding the the keypad, other than that it seems to work.I get the Inverse 'K' on the screen. runs bloody hot those. I have re-soldered all of the IC pins and it made no difference.

I may consider getting rid of it,but would want to re-coupe the cost of a recently purchased new keypad.
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1024MAK
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Location: Looking forward to summer in Somerset, UK...

Re: ZX81 ULA wanted

Post by 1024MAK »

If you get another, you can keep the top half of the case with the new keyboard ;)

If you don't want to buy another ZX81, then I understand what you are saying.

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
User avatar
1024MAK
Posts: 5087
Joined: Mon Sep 26, 2011 10:56 am
Location: Looking forward to summer in Somerset, UK...

Re: ZX81 ULA wanted

Post by 1024MAK »

A member on World of Spectrum forums has ULAs for sale, see this thread .

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
arts
Posts: 2
Joined: Fri Nov 10, 2017 5:46 pm

Re: ZX81 ULA wanted

Post by arts »

I have a zx81 still in original packaging if anyone is interested
Lardo Boffin
Posts: 2155
Joined: Sat Nov 26, 2016 2:42 am

Re: ZX81 ULA wanted

Post by Lardo Boffin »

Mutant Caterpillar Games have a bunch of tested (heat sink’d / sunk? Don’t tell Moggy regardless....) ULAs up for sale at the mo on Sell My Retro.
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
Moggy
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Joined: Wed Jun 18, 2008 2:00 pm

Re: ZX81 ULA wanted

Post by Moggy »

"Do you expect me not to use a heat-sink Moggy?"..."No Mr Lardo I expect you to die!"
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Lardo Boffin
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Joined: Sat Nov 26, 2016 2:42 am

Re: ZX81 ULA wanted

Post by Lardo Boffin »

The names Boffin.... Lardo Boffin, he thought as he watched the ULAaser get dangerously close to bits that’s don’t need to be heated up.

If only my latest gadget from Q-bay can help me?

328B6967-D52C-4714-83A3-F946EA9F7E1A.jpeg
(775.21 KiB) Downloaded 367 times
He wondered where it was best to attach it to the motherboard and how he could do it with only a magnetic Omega while strapped to the table...
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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