Dot crawl and keyboard membrane.

From	philicorda <philicorda@sorrynospam.com>
Subject	Dot crawl and keyboard membrane.
Newsgroups	comp.sys.sinclair
Message-ID	<gUAEu.7$_25.4@fx18.am4> (permalink)
Organization	virginmedia.com
Date	2014-01-24 21:26 +0000

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Hello.
I have recently got my ZX spectrum 48 working with a new keyboard 
membrane. Unfortunately, it has dot crawl like a protest march of 
infuriated gnats. Tweaking the tweakable capacitor doesn't make much 
difference. It seems to be better sometimes when the computer isn't 
thinking too hard, if that makes any sense.

What I'm wondering is if I have routed one of the ribbon cables from the 
keyboard the wrong way, and it's interfering with the video circuitry. I 
have some vague memory that the left side one was bent under the 
keyboard, rather than towards the back of the computer, before I replaced 
it.

Anyone know what the correct way is? I don't really want to take it apart 
to experiment without knowing as it was a bit tricky to put together, and 
the cables don't look like they should be flexed much.

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Dot crawl and keyboard membrane. philicorda <philicorda@sorrynospam.com> - 2014-01-24 21:26 +0000
  Re: Dot crawl and keyboard membrane. "Brian Gaff" <briang1@blueyonder.co.uk> - 2014-01-25 05:07 +0000
    Re: Dot crawl and keyboard membrane. philicorda <philicorda@sorrynospam.com> - 2014-01-26 22:36 +0000
    Re: Dot crawl and keyboard membrane. Robert Newson <nothanks@bullet3.fsnet.oc.ku> - 2014-02-09 16:39 +0000
      Re: Dot crawl and keyboard membrane. greenaum@gmail.com (greenaum) - 2014-05-21 18:59 +0000
        Re: Dot crawl and keyboard membrane. "Brian Gaff" <brian1gaff@gmail.com> - 2014-05-25 23:58 +0100
          Re: Dot crawl and keyboard membrane. Hanno Foest <hurga-news2@tigress.com> - 2014-06-01 20:35 +0200

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