Some of these sites already have a internet-connected temperature sensor on a PCB inside a unvented plastic (electronics) enclosure inside the outdoor weatherpoof metal enclosure. With just a quick look, I found one which slewed from 21C to 65C over 2 hours within the last couple weeks. I don't have enough data from that day to tell how much of that 44C was during a short period - I only have the two samples 2 hours apart.
It's amazing how quickly though a bit of sun on a grey metal box will heat the box insides up. Cooling is a lot slower though. I will say though that the idea of adding some thermal mass/insulation around the oscillator to reduce the temperature change during holdover is something I'm going to investigate. On Fri, Sep 25, 2020 at 3:50 AM Hal Murray <hmur...@megapathdsl.net> wrote: > > > 1) In an unconditioned/semi-conditioned space. The ambient temperature > can > > slew 20*C easily over the holdover period. (Think sun hitting an > outdoor > > enclosure first thing in the morning - the ambient temperature tends to > rise > > quickly). > > It would be interesting to get some data on that. Clouds blocking the sun > or > holes in the cloud cover would be a variation. > > If the sun hits the enclosure, how long does it take the air inside to > heat up > and then how long does it take the gear inside to warm up? > > One of the classic tools for problems like this is to attach a big blob of > stuff to the crystal to dampen thermal changes. When you design your test > setup, can you leave room for a brick and collect data with and without > when > you toss it into the freezer? > > -- > These are my opinions. I hate spam. > > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > -- - Forrest _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.