I have Sharp countertop microwave oven model R-428JKF That has problems 
that seems more like an intermittent "start" switch. The switches  are 
on one PCB, the electronics (cpu) are on another , and the display  on 
what appears to be a glass or clear plastic plate. The PCB board has 
card edge consisting of approximately 50 parallel maybe 20 gauge nickel 
or silver plated wires , the wire diameter flat is on the board with a 
pitch of .05" approximately. These wire contacts are against a flexible 
plastic strip 2.1" long, 1/4" high (perpendicular to PCB and length of 
wires), and 0.115" thick (parallel to PCB surface). The plastic strip 
consists of 3 laminations, interface in the perpendicular to the PCB 
board. The outer laminations are translucent clear, and the center 
lamination is dark grey. The other edge of the plastic strip at one end 
contacts a flexible plated on mylar ribbon cable with 13 conductors and 
silver or nickel plated contact surfaces. Next to the ribbon cable there 
are no metallic contacts, but just a clear glass or plastic surface 
which seems to have a ghost of contacts, or maybe just impression of the 
plastic strip. This is the 2nd time I have cleaned the area with 
tuner/contact cleaner and it works fine for 4 months or so with daily 
use, and then the "start" button gets more intermittent. It seems to 
work for a few cycles if one unplugs the unit briefly, and then you can 
push the button all you want with zip. :(

I also scrapped a DMM recently that had a similar connector and display 
problems.

Can someone explain the technology of this strange connection with 50 
circuits on one side, 13 on the other along with a clear surface? And is 
there something else I can do to improve the situation?  :)
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