Spectrum +3 membrane water ingress

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

Spectrum +3 membrane water ingress

Post by Lardo Boffin »

Hello all

I have just bought a +3 and when booted it goes straight to the loader option. I disconnected the keyboard and it no longer does this.
I took the keyboard out and removed a lot of dust bunnies and tried again but still the same.
I finally took out the membrane to find this:

2C6960B4-35CE-4A6D-9300-6AE324500F48.jpeg

Some sort of liquid inside the membrane. Clearly a spillage at some point although the keys were clean. If I squeeze the membrane the liquid moves around still!

Is there any way of dealing with this? Currently I have the membrane in a warm dark place in the vague hope it will dry out but I am not convinced it will.

I also cannot find any for sale anywhere. :cry:
ZX80
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1024MAK
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Re: Spectrum +3 membrane water ingress

Post by 1024MAK »

The trouble is, what liquid is it?
As if it is not pure water (which is very unlikely), if it does dry out, it will leave a deposit behind, which may be partly conducive. Or it may be sticky or crusty and may mess up the key contacts.

Now, as far as I know, the only source of +2A / +2B / +3 membranes, is existing computers. Unless someone has a stash of Amstrad ones hidden somewhere. As they are normally reliable, there is insufficient demand for new spares, so as far as I know, no one makes them.

But back to your membrane. You need to find a way to partly split the layers (in a non-critical place) so that you can force clean water in between the layers and then out somewhere. Then after this wash, pump dry pressured air through it.

Good luck!

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

Re: Spectrum +3 membrane water ingress

Post by Lardo Boffin »

Thanks Mark. Thats as much crud as I dare remove:

AC5F19F1-8E33-4463-ABA2-29550112035F.jpeg

Now to wait patiently for a couple of days while it dries! :shock:
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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Dim_75
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Joined: Fri Sep 01, 2017 11:04 pm
Location: Paris, FR

Re: Spectrum +3 membrane water ingress

Post by Dim_75 »

Hello, do you find this +3 on ebay last week ?
I saw one for sale and on the pictures on the +3 it was wet with a few bubbles :shock: .
Clearly the seller made a quick cleaning with a kind of soap and water or something like this...
(I did"nt bid on the +3 after that)

Hope it will be ok once dry !
Lardo Boffin
Posts: 2160
Joined: Sat Nov 26, 2016 2:42 am

Re: Spectrum +3 membrane water ingress

Post by Lardo Boffin »

I did get it from eBay last week but this one didn’t show any signs of being wet in the photos. I have seen them like that!

To be fair the outside of the case is a lot less dusty than the inside so it could have been over enthusiastically cleaned before sale. :o
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
Posts: 2160
Joined: Sat Nov 26, 2016 2:42 am

Re: Spectrum +3 membrane water ingress

Post by Lardo Boffin »

A couple of days later...

It has dried out with minimal water marks visible and all the keys now seem fine! Not tried every combination yet but looking good so far.
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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