Path: utzoo!attcan!uunet!lll-winken!ames!mailrus!cornell!rochester!uhura.cc.rochester.edu!ur-valhalla!davis
From: davis@galaxy.ee.rochester.edu (Al Davis)
Newsgroups: comp.sys.zenith.z100
Subject: Re: Z100 keyswitches
Message-ID: <1719@valhalla.ee.rochester.edu>
Date: 10 Jan 89 04:21:16 GMT
References: <601@unocss.UUCP> <12461185813.12.GUBBINS@RADC-TOPS20.ARPA>
Sender: usenet@valhalla.ee.rochester.edu
Reply-To: davis@ee.rochester.edu (Al Davis)
Organization: UR Dept. of Electrical Engg, Rochester NY 14627
Lines: 19



I have been successful at "fixing" them.

Unsolder the contacts (there are 2).  Use solderwick, braid with flux, etc.

Squeze the clips that hold it to the metal plate, and lift with a small
screwdriver, rocking it.

Open it: bend slightly the plastic tabs on the side.  It comes apart.  Don't
bend too much; they break.

Inside, there is a coil spring, a bent flatish piece of metal, and a
membrane switch.  The problem is that it gets fatigued.  To fix, bend the
flatish piece so it puts a little more pressure on the membrane, then
reassemble.

With too little pressure, it will either bounce or make no contact.  With
too much pressure, it makes conatct all the time