On Tue, 19 Nov 2013 17:54:37 -0800 (PST), Bill Bowden
I think you'd just be delaying the inevitable by padding the
resistance.
Pay attention to sealing where the leads enter the cell in the back,
as well as the surface,
It's been awhile since I used a CDS cell, but I seem to remember there
was a visible change in the moisture damaged cells versus new ones.
Take a magnifying glass to it... you may be able to see where the
moisture entered - comparing it to a new one. The silvery stuff turns
darker.
Providing you don't need a lot of current, a photo transistor can
replace a CDS cell in a DC circuit. Not good for operating relays
directly - but if your switch point is 27K you probably aren't using a
relay. For the hell of it I put a photo transistor across my
ohmmeter. Total darkness is >2 meg ohms, the light from my computer
screen ~8K, holding it close to a desk lamp ~100 ohms. I wonder that
someone doesn't already make CDS replacements with a couple of back to
back parallel photo transistors.
Back in the germanium age, we would hack the metal covers off power
transistors, pour in epoxy and make photo transistors that would
operate (sensitive) relays directly.
BTW Bill Bowden were/are you the same guy on the TC mailing lists some
time in the 90's?