Alphacom 32 PSU?

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Moggy
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Re: Alphacom 32 PSU?

Post by Moggy »

Plug on the printer.

Socket on the power supply.

Same plug size as zeddy power pack and obviously corresponding socket.

Make sure wires well separated/insulated from each other as it is a tight fit in side the plug/socket and do connect together before powering up as even 20 odd volts ac can do a bit of damage if briefly shorted out plugging the plug into the socket when powered up.


Edit.

Just noticed your power pack looks to be 28.8 volts at 1 amp ,the original is 24 volts at 1.2 amps couldn't say if that's crucial or not but obviously a replacement judging by the look of it.
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printer.png
Lardo Boffin
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Re: Alphacom 32 PSU?

Post by Lardo Boffin »

Thanks Moggy!

I will see if I can get hold of a properly rated PSU. Not sure the extra 4V will cause damage but would rather not risk it.
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siggi
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Re: Alphacom 32 PSU?

Post by siggi »

A typical voltage resistance of capacitors (inside the printer) is 35V. This value fits to a rectivied AC voltage of 24V, but not to more (the capacitor may explode).

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siggi
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Re: Alphacom 32 PSU?

Post by siggi »

Moggy wrote: Mon May 31, 2021 12:08 am Same plug size as zeddy power pack and obviously corresponding socket.
No, Zeddy uses 3,5 mm plugs, the printer 2,5 mm plugs.
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Lardo Boffin
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Re: Alphacom 32 PSU?

Post by Lardo Boffin »

Thanks all. Even if 28V doesn’t cause damage I don’t trust one that has been taped together. :shock:

So I have until Xmas to sort a new PSU then - all this will be used for is printing the inside of retro xmas cards!
ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
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TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
Moggy
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Re: Alphacom 32 PSU?

Post by Moggy »

siggi wrote: Mon May 31, 2021 9:54 am
Moggy wrote: Mon May 31, 2021 12:08 am Same plug size as zeddy power pack and obviously corresponding socket.
No, Zeddy uses 3,5 mm plugs, the printer 2,5 mm plugs.
Must have been the Venusian loobdingle translation matrix I was using, sorry. ;)


@Lardo.

And don't forget to put the tenner inside my card this year, you forgot last time. :lol:
Lardo Boffin
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Re: Alphacom 32 PSU?

Post by Lardo Boffin »

Moggy wrote: Mon May 31, 2021 1:19 pm
siggi wrote: Mon May 31, 2021 9:54 am
Moggy wrote: Mon May 31, 2021 12:08 am Same plug size as zeddy power pack and obviously corresponding socket.
No, Zeddy uses 3,5 mm plugs, the printer 2,5 mm plugs.
Must have been the Venusian loobdingle translation matrix I was using, sorry. ;)


@Lardo.

And don't forget to put the tenner inside my card this year, you forgot last time. :lol:
I’ll print one but not sure you will be able to spend 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
PaulUK
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Re: Alphacom 32 PSU?

Post by PaulUK »

I recently bought an Alphacom 32 with no PSU so I'm about to search for one. Does anyone know if its 24V peak to peak, or 24V RMS? Better still, can anyone recommend a reliable replacement available in Germany? Thank you.
daveZX4th
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Re: Alphacom 32 PSU?

Post by daveZX4th »

The PSU supplied with my brand new Alphacom 32 is same as image here

A few years ago I measured output as 30V AC (RMS) offload, dropping to 27.7V at 0.87A when the printer was chugging away.
PaulUK
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Re: Alphacom 32 PSU?

Post by PaulUK »

Thanks, thats useful to know. Ill see if I can find something similar.
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