All my portable phones seem to be dying the same way.
In particular; take my Vtech gigaphone. This phone, like the
others in the house, has a large flexible membrane
which implements the unit's push buttons. When the
phone was new, a soft, quick touch successfully entered the
number. Now the keys require a long steady pressure before
the phone senses the push.
I opened up one phone and removed the membrane. It has black colored
conductive (I think conductive) backing material just under
each button When the button is pushed the black areas
contact lands on the pwb. I cleaned the unit using just
water but it didn't help.
Is there some kind of dielectric paste or conditioner
which must be reapplied? Must the carbon contacts be
specially rejuvenated with some chemical?
The lands on the pwb are clean.
How can this be fixed?