A dead ULA that I have to hand, is a ULA2C184E date code 8206, underside marked 2C184E 0317.
Z80 CPUs also often have markings underneath, a dead Zilog one, marked SL102-1 ZCPU 8400S date code 8150 PS has 8PHILAA002AJ marked on the underside.
Mark
"Different" ZX81's
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1024MAK
- Posts: 5532
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- Location: Looking forward to summer in Somerset, UK...
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Re: "Different" ZX81's
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Spring approaching...
ZX81 Chip Pin-outs
ZX81 Video Transistor Amp
Standby alert There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Spring approaching...
Re: "Different" ZX81's
Wooop! Dead chuffed to have an early-as-you-can-get ZX81 - especially as this one works 
- 8102.jpg (120.52 KiB) Viewed 4847 times
ZX80, ZX81 - 2C158C Bugged Rom iss.1, 2C158C "kludge fix" iss1, 2C184E iss1, 2C210E iss3, US NTSC iss1 "straight traces", US NTSC iss3 TS1000
Re: "Different" ZX81's
OOO a nice clean example there Mr Wappy.
Zilog motor very early ULA and a socketed Mostek RAM chip, a lovely purchase Sir.
Zilog motor very early ULA and a socketed Mostek RAM chip, a lovely purchase Sir.
???????????????????????????PIINKEY$?????RND????????????????????????????????????????????????????????PI????????
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Lardo Boffin
- Posts: 2256
- Joined: Sat Nov 26, 2016 2:42 am
Re: "Different" ZX81's
A slightly more recent ZX81. Also working, well, apart from the keyboard. Need to see if trimming it down will help.
There is nothing printed on the underside of the ULA.
Produces a very dark but quite good picture!
Now where are those ZX8-CCBs?...
There is nothing printed on the underside of the ULA.
Produces a very dark but quite good picture!
Now where are those ZX8-CCBs?...
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
Re: "Different" ZX81's
Wow nice one Lardo another great example.
At the rate you two are buying up surplus zeddies you will be giving Rich a run for his money!
At the rate you two are buying up surplus zeddies you will be giving Rich a run for his money!
???????????????????????????PIINKEY$?????RND????????????????????????????????????????????????????????PI????????
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Lardo Boffin
- Posts: 2256
- Joined: Sat Nov 26, 2016 2:42 am
Re: "Different" ZX81's
You have no idea...
I have not bought any for a while as I was always outbid. So I put low ball bids on a number of interesting looking boxed zeddys (4) and won them all!
This is number one.
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
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
- Posts: 5532
- Joined: Mon Sep 26, 2011 10:56 am
- Location: Looking forward to summer in Somerset, UK...
- Contact:
Re: "Different" ZX81's
I'm glad that I'm not competing with you then 
Mark
Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Amp
Standby alert
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Spring approaching...
ZX81 Chip Pin-outs
ZX81 Video Transistor Amp
Standby alert There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Spring approaching...
Re: "Different" ZX81's
???????????????????????????PIINKEY$?????RND????????????????????????????????????????????????????????PI????????
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Lardo Boffin
- Posts: 2256
- Joined: Sat Nov 26, 2016 2:42 am
Re: "Different" ZX81's
I'm fully spent up for the minute thanks!Moggy wrote: ↑Mon Mar 20, 2017 4:18 pm Here you go boys have a crack at this one!
http://www.ebay.co.uk/itm/SINCLAIR-ZX81 ... Sw4A5YzuYI
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
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
Re: "Different" ZX81's
Lardo Boffin wrote: ↑Mon Mar 20, 2017 3:32 pm A slightly more recent ZX81. Also working, well, apart from the keyboard. Need to see if trimming it down will help.
IMG_5669.JPG
Well now - you've got one of those ULA's!
I reckon they are 2C184e ULA, but not as you normally see them with the ULA code marked on top. The 2C184e first appeared 8128, with the last 2C154e being made in 8127. Notice that the font is different to the type used on the 2C158e and that it's offset. Just a hunch on my part. The other one if these I've seen is also on a cream PCB.
@Moggy - Thanks - I'm mega-chuffed to get that ZX81. The review in PCW shows one of the same age, but all the other reviews show a later ones. Must admit its my pride and joy
ZX80, ZX81 - 2C158C Bugged Rom iss.1, 2C158C "kludge fix" iss1, 2C184E iss1, 2C210E iss3, US NTSC iss1 "straight traces", US NTSC iss3 TS1000