Lardo buys another zeddy

ZX80 / ZX81 hardware and software offered for sale or swapping
rmbrowngr
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Joined: Thu Dec 09, 2021 2:58 pm

Re: Lardo buys another zeddy

Post by rmbrowngr »

Lardo Boffin wrote: Tue Feb 07, 2023 5:03 pm Might be a while before I do anything with this one though as I seem to have run Ginger Electronics out of keyboards… :oops:
I’m waiting for them come back into stock as well.
ZX81 (purchased November 1982), my first computer.
ZXpand+, ZX8-CCB.
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1024MAK
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Re: Lardo buys another zeddy

Post by 1024MAK »

rmbrowngr wrote: Tue Feb 07, 2023 9:40 pm
Lardo Boffin wrote: Tue Feb 07, 2023 5:03 pm Might be a while before I do anything with this one though as I seem to have run Ginger Electronics out of keyboards… :oops:
I’m waiting for them come back into stock as well.
Well, don’t let Lardo get in first… Or you may wait for even longer :roll: :lol:

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Lardo Boffin
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Re: Lardo buys another zeddy

Post by Lardo Boffin »

True, there will only be 50 of them…
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
rmbrowngr
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Re: Lardo buys another zeddy

Post by rmbrowngr »

ZX8-KDLX - 50 pieces from 15.02.2023 !!!

Have to be quick next week :lol:
ZX81 (purchased November 1982), my first computer.
ZXpand+, ZX8-CCB.
rmbrowngr
Posts: 27
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Re: Lardo buys another zeddy

Post by rmbrowngr »

ZX8-KDLX ordered!! There were a few left :lol:
ZX81 (purchased November 1982), my first computer.
ZXpand+, ZX8-CCB.
Lardo Boffin
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Re: Lardo buys another zeddy

Post by Lardo Boffin »

A superb working issue one and RAM pack. The RAM PACK was working when it arrived but died after half an hour of soak testing. Hey ho.

1F8DC254-3B33-40E1-BEBA-DDDFCDDBF25C.jpeg

Check out the logo. Almost perfect.

D7261FE9-8D42-4135-8972-E8DADACFC6E9.jpeg

Clearly been repaired at some point:
2F7152D3-5DD6-4CF7-836D-0993AE0EFE6B.jpeg
835FE426-B542-4798-9AC0-E8374DA26DBE.jpeg
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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Paul
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Location: Germanys west end

Re: Lardo buys another zeddy

Post by Paul »

Lardo the RAM Killer :twisted:
In theory, there is no difference between theory and practice. But, in practice, there is.
Lardo Boffin
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Joined: Sat Nov 26, 2016 2:42 am

Re: Lardo buys another zeddy

Post by Lardo Boffin »

I didn’t mean to honest! I was just soak testing it before re-homing it.
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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Paul
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Location: Germanys west end

Re: Lardo buys another zeddy

Post by Paul »

Before trying out I do the following tests:
First I measure the voltage of the original PSU.
If it out of range in the DC-Mode => don't use it.
If it shows something in AC mode => don't use it.
The zeddy normally needs no recap so just test it.
If it works but doesn't startup reliable (needs more than one try occasionally) => recap it.
Then to the 16K RAMPacks
They create the voltages required by heavy use of electrolyte Capacitors. One voltage wrong kills the dynamic RAMs.
So never try it without recap first! It's lethal!
In theory, there is no difference between theory and practice. But, in practice, there is.
Lardo Boffin
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Joined: Sat Nov 26, 2016 2:42 am

Re: Lardo buys another zeddy

Post by Lardo Boffin »

Thanks!

I was trying it on my zeddy with a good PSU, so I guess it was the caps inside the RAM pack.

Lesson learnt!

If I recap it and socket the RAM I can presumably work out which one(s) are dead and fix it?
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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