Yellow PCB Issue One ROM type

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Lardo Boffin
Posts: 1763
Joined: Sat Nov 26, 2016 2:42 am

Yellow PCB Issue One ROM type

Post by Lardo Boffin »

Having bought a couple of zeddies in the past I recently got two in short succession which had the rarer yellow PCB and type 622 ROMs - the slightly rarer intermediate ROM we are now familiar with.
From seeing two together I wondered if I had seen any more so had a look through some photos…

https://sinclairzxworld.com/viewtopic.p ... 229#p35229
ULA 8128

https://sinclairzxworld.com/viewtopic.p ... 546#p36546
ULA 8132

https://sinclairzxworld.com/viewtopic.p ... 869#p42869
ULA 8130

https://sinclairzxworld.com/viewtopic.p ... 331#p46331
ULA 8128

https://sinclairzxworld.com/viewtopic.p ... 622#p46622
ULA 8141 (may not be - 622 ROM)

https://sinclairzxworld.com/viewtopic.p ... 765#p46765
ULA 8132

https://sinclairzxworld.com/viewtopic.p ... 036#p47036
ULA 8138

Anybody else got / seen a yellow PCB issue one? Does it have a 622 ROM? Just curious!
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
Lardo Boffin
Posts: 1763
Joined: Sat Nov 26, 2016 2:42 am

Re: Yellow PCB Issue One ROM type

Post by Lardo Boffin »

Or a 622 ROM that is not on a yellow PCB?
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
Posts: 2759
Joined: Wed Jun 18, 2008 2:00 pm

Re: Yellow PCB Issue One ROM type

Post by Moggy »

"Yellow" PCB? more like beige to my old eyes! :lol:


All my ROMs have been replaced by big bang double speed EPROMs but a quick shufty reveals that four of my boards, three beige one green all had 622 ROMS and I only have two 649's, one being a Mostek and the other is the Motorola I got from your good self.
Lardo Boffin
Posts: 1763
Joined: Sat Nov 26, 2016 2:42 am

Re: Yellow PCB Issue One ROM type

Post by Lardo Boffin »

I guess it is more beige than yellow.

Quite a few yellow / beige PCBs with the 622 then. Were they a similar date code to mine?
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
Posts: 2759
Joined: Wed Jun 18, 2008 2:00 pm

Re: Yellow PCB Issue One ROM type

Post by Moggy »

The two 622s I have to hand are NEC jobbies and not sure how their date code works but they are numbered P18359-192 and P19209-137.
The Mostek is 1982. Can't tell from ULA's as I swapped them all out for Andy Rea's little green marvels and they are in a box somewhere.
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