> I have had a lot of people who report their QLs have not been used > for many many years. They worked fine when hibernated, but membranes > failed while not used. This happens because the tails are bent round > in a tight 180% degrees, and the bend is under tension.
Exactly what happened to mine. A crack right across the fold, after hibernating in its original box for a few years. I hung onto it for a number more years, intending to see if I could get it fixed, but never quite got around to it. Eventually I assumed it was too late and chucked it out (minus any removable ICs and the microdrives). I wish I'd kept it now... Ian. > -----Original Message----- > From: tony > Sent: 08 March 2002 15:33 > To: ql-users > Cc: tony > Subject: Re: [ql-users] Membranes > > > On Fri, 8 Mar 2002 at 06:20:22, Al Feng wrote: > (ref: <[EMAIL PROTECTED]>) > > >EVERYONE! > >� > >Speculation about the material used in the QL's membranes by Sinclair > >or otherwise seems futile. > >� > >It is worth noting, IMO, that the reason that the membranes > have failed > >in the past, and will probably fail in the future in a standard QL > >configuration IS singularly BECAUSE of the proximity to the heatsink. > >� > >Think about it. > >� > >As long as the standard PS configuration is used, you are baking the > >tails.� The rest of the keyboard membrane does not appear to suffer > >from the problem of becoming brittle. > >� > >If you want to make a BETTER *membrane*, then get hold of a > TS-2068 and > >see how Timex made their keyboard -- printed circuit, carbon pads to > >close the circuit, ribbon wire tails attached to a connector. > > >� > >Worrying about the pressure needed to actuate a "key" is a silly > >exercise if you are simply trying to create a replica of the original > >membrane because your keyboard membrane's tails will > inevitably suffer > >the same fate which the original membranes experienced ... > Nope. As I said earlier in this thread, Sinclair used a good clear > plastic for earlier machines, and this is 100% OK. I know this 'cos I > have a few and seem to last for ever and are showing no sign at all of > failing. The conducting strips also show little sign of oxidisation - > and these all date from 1984. My experience of the std membranes is > that they become brittle on exposure to air. Heat simply accelerates > this. I have had a lot of people who report their QLs have > not been used > for many many years. They worked fine when hibernated, but membranes > failed while not used. This happens because the tails are bent round > in a tight 180% degrees, and the bend is under tension. > > > -- > QBBS (QL fido BBS 2:252/67) +44(0)1442-828255 > <1stname>@<surname>,demon.co.uk http://www.firshman.demon.co.uk > Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 > TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG > Visit our website at http://www.ubswarburg.com This message contains confidential information and is intended only for the individual named. If you are not the named addressee you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately by e-mail if you have received this e-mail by mistake and delete this e-mail from your system. E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses. The sender therefore does not accept liability for any errors or omissions in the contents of this message which arise as a result of e-mail transmission. If verification is required please request a hard-copy version. This message is provided for informational purposes and should not be construed as a solicitation or offer to buy or sell any securities or related financial instruments.
