Keyboards & Conductive Rubber

From: J.C. Wren <jcwren_at_jcwren.com>
Date: Tue Sep 7 07:49:52 2004

    How about copper foil tape, like that used by stained glass people?
I use this stuff all the time when I do prototyping, usually to lay down
power and ground "traces". I also use it for ground planes under
switchers and RF sections. And for hacks like this:
http://tinymicros.com/gallery/hasselblad

    --jc

Dave Dunfield wrote:

><snip>
>
>

>Paul:
>
>
>> I've tried several things on my Sony TV remote control. The various
>>paints and other expensive fixes don't last very long. What finally worked
>>for me was some heavy aluminum foil tape used for sealing air ducts.
>>
>> Cut some tiny squares of the tape just big enough to cover the two
>>contact pads on the circuit board and stick it to the surface of the key
>>plunger. Evidently the resistance value is not critical, as long as it's
>>below some minimum value -- zero ohms is OK. My repair has been working for
>>a couple of years now.
>>
>> You can find the tape at home centers (Lowe's/Home Depot), and appliance
>>or plumbing parts suppliers.
>>
>>
>
>
>Hi Guys,
>
>THANKS for the good ideas...
>
>I think I like the tape idea the best - I had thought about trying to glue
>in a bit of tinfoil - I've done that for "round" pads, however these are
>very thin/long pads, and the tape might be easier to work with.
>
>Btw, they are NOT the kind where the PCB pads are interleaved "fingers" -
>these are two separete pads which are perhaps as much as 1/8" apart - the
>rubber bit is nearly 1/4" long and has a "bump" on each end to contact
>the pads - this means that the rubber flexes as it pushes down, and I
>think that graphite or paint would probably crack and flake off.
>
>I don't think it would be easy to replace the rubber pads, as you would
>need the right shape, and also the pad is bonded to a little strip of
>material like this (cross sectional view):
>
>
> | | <= Key plunger
> | |
> +--------+
> | | <= open space
> +--------+ <= "Carrier strip"
> [====] <= Conductive Rubber Pad
>
>
>Btw, this is for a Commodore PET - I just remembered that I have an
>extra C64 keyboard, so I'm going to pull it apart and see if by any
>miracle the key assembly is the same.
>
>Regards,
>
>Dave
>
>
Received on Tue Sep 07 2004 - 07:49:52 BST

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:37:27 BST