[Milsurplus] R-390 hints

[KD7JYK DM09]

"I used a small syringe with de-oxit to get to the contacts."

I've recently discovered, and been using QD Plastic/Sensor Safe Electric 
Contact cleaner, from WalMart, in a red can, to hose down things I can't 
easily get to, without any ill affects.  Initially, I was nervous, 
because I've destroyed, or melted far too many things over the decades, 
but I have yet to find anything this damages, other than grease, dirt, 
dust, grime, et cetera.  I've used this product dozens of times, over 
several years, on wiring harnesses, motors, circuit boards, bearings, 
plastic connectors of many, many types, plastic case, screens, paints, 
things you usually wouldn't want to expose to much more than just air, 
with no problems at all. It's something to take into consideration.  I 
would NOT, personally, try soaking an item, I'm sure everything has a 
failure point, but to blast, and hose out, I've yet to see an issue.

Kurt