Refurbing an issue one zeddy

Discussions about Sinclair ZX80 and ZX81 Hardware
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amigaman07
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Location: Newcastle Australia

Re: Refurbing an issue one zeddy

Post by amigaman07 »

:mrgreen: On another Note, and I may get "STONED" for this too...

My Original ZX81 UK 700 Power Supply DIED the Death!

When I opened it up, all the Caps & Resistors Pass the Tests!

I think it is actually the "TRANSFORMER" that Died (Big Black thing with Lots of Copper Wires Wrapped around it)

(Anyone know where I can get another???)

I thought about De-Soldering the Lead and attaching it to a ZX Spectrum 48k UK 1400 Power Supply, but then I would need another ZX Spectrum PSU!

Sooo, I am currently using... Dare I say it?...

An ATARI 2600 WOODY Power Supply! :roll:

It err, Does Work! :mrgreen:

Darren in OZ
Lardo Boffin
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Joined: Sat Nov 26, 2016 2:42 am

Re: Refurbing an issue one zeddy

Post by Lardo Boffin »

amigaman07 wrote: Wed May 10, 2017 1:55 am "cosmetically too poor to sell on with good conscience"

Looks in Better Condition than My Timex 1000 ! :cry:

Whats this about "HEAT SINKs"???

:lol:

Darren in OZ
It's the case that's a bit beat up. The keyboard works but has loads of dents.

Don't mention heat sinks!!!!!!
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
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Re: Refurbing an issue one zeddy

Post by Lardo Boffin »

amigaman07 wrote: Wed May 10, 2017 2:02 am :mrgreen: On another Note, and I may get "STONED" for this too...

Sooo, I am currently using... Dare I say it?...

An ATARI 2600 WOODY Power Supply! :roll:

It err, Does Work! :mrgreen:

Darren in OZ
I say this with the greatest affection for Sinclair stuff (I have a lot of it) but improvisation was very much the name of the game with Sir Clive and his team! What you are doing is very much in character with the zeddy!
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
sirmorris
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Re: Refurbing an issue one zeddy

Post by sirmorris »

Get a modern regulated supply of something like 7.5-8 volts. The regulator will run cooler and your zeddy will thank you.
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amigaman07
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Location: Newcastle Australia

Re: Refurbing an issue one zeddy

Post by amigaman07 »

Hi Lardo Boffin.

RE: "The keyboard works but has loads of dents."

The Owner of this Site can supply you with a Cheap New REPRODUCTION Keyboard, Better than the Original! :shock:

And is Cheap as Chips! :o

Darren
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1024MAK
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Re: Refurbing an issue one zeddy

Post by 1024MAK »

amigaman07 wrote: Wed May 10, 2017 2:02 amMy Original ZX81 UK 700 Power Supply DIED the Death!
<snip>
I think it is actually the "TRANSFORMER" that Died (Big Black thing with Lots of Copper Wires Wrapped around
Far more likely that the thermal fuse (mounted either between the transformer and the PCB, or under the tape that covers the primary winding, the fuse is on the top layer of the winding) has gone open circuit.

If you are careful, sometimes it is possible to replace these with new ones. If you do, note that you have to use a heat shunt otherwise you risk blowing it with the heat from the soldering iron :lol:

Mark
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Lardo Boffin
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Re: Refurbing an issue one zeddy

Post by Lardo Boffin »

amigaman07 wrote: Wed May 10, 2017 1:33 pm Hi Lardo Boffin.

RE: "The keyboard works but has loads of dents."

The Owner of this Site can supply you with a Cheap New REPRODUCTION Keyboard, Better than the Original! :shock:

And is Cheap as Chips! :o

Darren
Thanks! I have bought a few of these but when the keyboard works perfectly I don't really like to change 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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povvercrazy
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Re: Refurbing an issue one zeddy

Post by povvercrazy »

amigaman07 wrote: Wed May 10, 2017 2:02 am :mrgreen: On another Note, and I may get "STONED" for this too...

Sooo, I am currently using... Dare I say it?...

An ATARI 2600 WOODY Power Supply! :roll:

It err, Does Work! :mrgreen:

Darren in OZ
I do have a tip, don't be half asleep and too eager to test your newly refurbished woody 2600
that you use a megadrive power supply .......the nice big 2200uf cap go boom boom :)
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amigaman07
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Location: Newcastle Australia

Re: Refurbing an issue one zeddy

Post by amigaman07 »

Ha ha,

I was going to say...

I use a "Megadrive 1" Power Supply on my ZX Spectrum 48k and my Commodore 16, WHOOPS... can I mention the "C" Word on this site? :o

Darren
Lardo Boffin
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Re: Refurbing an issue one zeddy

Post by Lardo Boffin »

1024MAK wrote: Wed May 03, 2017 12:06 am
As the modern switching regulators run cool, it's okay if they touch the case. As long as the case fits without stress on the parts.

Mark
A Tracopower TSR1-2450 is slightly too large to fit. Once in place there is a very slight bend on the motherboard which I figure is not ideal. So - back to soldering onto the legs of the previous incumbent...

Mark - your solution with the new wire wrapped around the end looks neat. What type of wire is it?

Also did the ROMs arrive ok?

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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