I want show you something curious...
In this picture, you can see on my mat a white/beige shadow line pointed by my red probe. That is the result after cleaning the black dirt from the membrane. Seems like that IPA removed with the dirt also the conductive material of the tracks on the membrane . So after the cleaning I've 0 keys working and I will buy one new the next weeks. I don't know if that is the result of corrosion or not, but on my mat now I have some some part of the membrane's tracks .
Trying to fix my ZxSpectrum+
- 1024MAK
- Bugaboo
- Posts: 3118
- Joined: Wed Nov 15, 2017 2:52 pm
- Location: Sunny Somerset in the U.K. in Europe
Re: Trying to fix my ZxSpectrum+
Yeah, I strongly advise against using IPA or any other solvent cleaner on any keyboard membrane.
For cleaning the plastic part of the membrane, only use a cloth moistened with soapy water, then another with clean water, then dry.
For the conductive copper "strips", you have to be rather careful as they are only a thin film. Apart from the areas where they connect to the PCB connector, and the area where two membrane layers connect together (plus keyboard only), don't worry about them going black in colour. The black colour may well be tarnish due to the copper actually being an alloy rather than pure copper (which goes green rather than black when exposed to moisture and oxygen).
Having said all that, it was probably unrepairable anyway.
Mark
For cleaning the plastic part of the membrane, only use a cloth moistened with soapy water, then another with clean water, then dry.
For the conductive copper "strips", you have to be rather careful as they are only a thin film. Apart from the areas where they connect to the PCB connector, and the area where two membrane layers connect together (plus keyboard only), don't worry about them going black in colour. The black colour may well be tarnish due to the copper actually being an alloy rather than pure copper (which goes green rather than black when exposed to moisture and oxygen).
Having said all that, it was probably unrepairable anyway.
Mark
Standby alert
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
“There are four lights!”
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb
Looking forward to summer later in the year.
- Muttley Black
- Microbot
- Posts: 119
- Joined: Wed Apr 03, 2019 3:31 pm
Re: Trying to fix my ZxSpectrum+
Now that you job is done and you have a working spectrum, don’t forget to give a good cleaning to your motherboard with isopropyl alcohol and toothbrush.
It is very important. I saw lot of flux on your soldering work.
It is very important. I saw lot of flux on your soldering work.
Re: Trying to fix my ZxSpectrum+
Hey long time i didn't post nothing, this week i'll go to an important flea market for electronic in Modena. I hope to find some spare parts for my ZX (rubber keyboard, capacitors, etc..). Lately i was busy to repair some C64.