On Wed, 03 Oct 2012 19:42:21 -0400, "
wrote:

My 39YO HP45 still works but the power switch is too flaky to be usable.

I collect old HP LED type calculators. The HP 45 is well worth fixing
and using.

The switches tend to fail due to dirt accumulation and/or wearing a
grove into the PCB contact area from overuse. I've repaired both
problems.
http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv018.cgi?read=131014
This is the dirt problem:
http://i45.photobucket.com/albums/f96/geoff_q/gunk.jpg
I couldn't find a photo of a grove worn in the contacts. I've been
quite successful with just cleaning the switch area. I've also
repaired missing gold problems with gold leaf. It was difficult,
required a microscope, a steady hand, no air movement, and
considerable patience.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558