On 4 Jun 2016 20:44, "Poul-Henning Kamp" <p...@phk.freebsd.dk> wrote: > > -------- > In message <57527f8a.6070...@yandex.com>, Charles Steinmetz writes: > > >As I have mentioned before, for many years I have put precision circuits > >that may be sensitive to humidity into gasketed metal boxes with fresh > >silica gel packets.
> Only thing to remember is that it also reduces air circulation in the > box and therefore increases thermal gradients. I don't know how practical they are, but I have see humidity calibration standards (e.g 50%). These use a chemical reaction to keep a volume at a constant humidity. That might be a way of keeping the humidity constant, without introducing increasing thermal gradients. They might introduce a whole host of other problems, so such a method would need researching. If a new PCB was designed, it would be nice if there were pads to take the expensive Vishay foil resistors, in addition to a cheaper choice. Dave _______________________________________________ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
