Spectrum +3 interesting mods on the solder side

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Lardo Boffin
Posts: 2160
Joined: Sat Nov 26, 2016 2:42 am

Spectrum +3 interesting mods on the solder side

Post by Lardo Boffin »

Hello all

Just got a +3 and noticed the following underneath:

693486A1-0830-4B9C-B8B8-AF87584969C5.jpeg
54C6A579-9E4D-4B84-BA4F-1011AA610E60.jpeg
DFFBF277-C6AE-4B4A-9DB2-3424B33B3704.jpeg
Any ideas what they do?

(Yes it needs a good clean!)

Thanks!

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: Spectrum +3 interesting mods on the solder side

Post by 1024MAK »

Have you checked against the known factory modifications? See here.

Mark
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Lardo Boffin
Posts: 2160
Joined: Sat Nov 26, 2016 2:42 am

Re: Spectrum +3 interesting mods on the solder side

Post by Lardo Boffin »

1024MAK wrote: Wed Nov 24, 2021 8:09 pm Have you checked against the known factory modifications? See here.

Mark
Thanks Mark. Looks like the factory fix for the Z70830 issue one board.
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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