Z88 power supply

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Sparrowhawk
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Z88 power supply

Post by Sparrowhawk »

My Z88 power supply has gone AWOL over the last few years. I've no idea where or when. Annoying, as I have a collection of power supplies for a whole bunch of stuff that I no longer even own, but I do still have my Z88 :D

Could somebody please tell me the spec for a replacement so that I can order one?


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Derek_Stewart
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Re: Z88 power supply

Post by Derek_Stewart »

Sparrowhawk wrote: Wed May 15, 2024 1:28 pm My Z88 power supply has gone AWOL over the last few years. I've no idea where or when. Annoying, as I have a collection of power supplies for a whole bunch of stuff that I no longer even own, but I do still have my Z88 :D

Could somebody please tell me the spec for a replacement so that I can order one?
The specification of the power supply. It should be 6.5v 500mA, maybe 6v may do it.

But check Rakewell

http://www.rakewell.com/z88/z88hardware_p.shtml


Regards,

Derek
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Pr0f
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Re: Z88 power supply

Post by Pr0f »

I'd err on the higher voltage side - the Sinclair PSU puts out about 6.5V, but 7.0 or 7.5 Volt, but the polarity is important! There is NO protection in the Z88 for reverse polarity - so check the documentation. From memory (and please don't rely on this info) it's the opposite of most common supplies.

Actually Rakewell site says centre positive - so that's normal for a lot of supplies.


ones' complement
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Re: Z88 power supply

Post by ones' complement »

Z88psu.jpg
Ideally you want one with an LED. I added one to mine since it was too easy to be unaware you were running on batteries and the mains switch wasn't on :?


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Sparrowhawk
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Re: Z88 power supply

Post by Sparrowhawk »

Thanks everyone, I'll go look for some online and if you don't mind before I potentially blow up the Z88 I'll post links here for what I've found for advice/confirmation before I press buy.


a.k.a. Jean-Yves
Derek_Stewart
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Re: Z88 power supply

Post by Derek_Stewart »

Hi,

I have another little job to fit Rom and internal ram upgrades to 2 of my Z88s.


Regards,

Derek
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Pr0f
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Re: Z88 power supply

Post by Pr0f »

I've done this on a couple of machines now, it's a worthwhile modification, but depending how you do it, it could mean cutting tracks. I also replaced the super cap with a larger value one, along with lower power memory devices, this extends the battery replace time and battery life, as the old supercaps are a bit leaky on quiescent current


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dilwyn
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Re: Z88 power supply

Post by dilwyn »

Just had a quick look on eBay for Z88s and accessories, feeling a little nostalgic after getting rid of my Z88 some years ago.

Like many retro systems, the prices they go for somewhat amazed me!


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Re: Z88 power supply

Post by ones' complement »

dilwyn wrote: Thu May 16, 2024 12:20 pm Just had a quick look on eBay for Z88s and accessories, feeling a little nostalgic after getting rid of my Z88 some years ago.

Like many retro systems, the prices they go for somewhat amazed me!
I occasionally look at Z88 on Ebay and it does appear fickle, some long standing listings are pricey but once in a while one goes under the radar and goes quite cheaply.


Derek_Stewart
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Re: Z88 power supply

Post by Derek_Stewart »

dilwyn wrote: Thu May 16, 2024 12:20 pm Just had a quick look on eBay for Z88s and accessories, feeling a little nostalgic after getting rid of my Z88 some years ago.

Like many retro systems, the prices they go for somewhat amazed me!
I have 2 Z88, which I have to upgrade, I will get them done and see if anyone want one.


Regards,

Derek
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