Hi Ok, if it’s a “heat only” design, how about a dewar flask? They aren’t the most rugged items out there so some sort of padded enclosure would be needed. The real question is:
Does a “single end” design impact your ability to use the resistor? Put another way - do you need to hit both ends of the device more or less directly? There are a variety of eBay sellers that will set you up with parts in a variety of shapes and sizes. As far as I can see, their designs would be reasonable for what you are trying to do. Back a while, the dewar was the enclosure of choice for a high grade OCXO. As people learned how to do ovens a bit better and the world decided they needed smaller parts, that approach fell by the wayside. It’s still a great way to get a reasonable oven that pulls pretty low power. Bob > On Jul 12, 2019, at 7:45 PM, Dr. David Kirkby > <drkir...@kirkbymicrowave.co.uk> wrote: > > On Fri, 12 Jul 2019 at 22:02, Hal Murray <hmur...@megapathdsl.net> wrote: > >> >> drkir...@kirkbymicrowave.co.uk said: >>> If it could run from a few NiMH cells for 48 hours, that would give the >>> option of shipping it. I don't know if that's going over the top, but it >>> would be an interesting exercise. >> >> Shipping a TEC cooler could get interesting. You need to get rid of the >> heat >> somehow. Cooling fins on a package would be interesting. > > > That is why I said that I would avoid a TEC. Running an oven should be less > problematic. > >> >> >> The airlines don't like dry ice. You could try an ice pack/gel. If it's >> well >> insulated, the TEC will be off. The heater won't take much power. It's >> just >> a matter of how much insulation you need. > > > I would not aim to ship by air, although at a push that might be possible. > > In the UK, in theory items can be shipped with batteries by Royal Mail > subject to some restrictions. Batteries inside equipment are okay up to > some capacity. Damaged cells or lose cells are not. In practice a lot of > staff in post office shops say no to batteries. > > I regularly get alkaline and NiMH batteries delivered from Farnel by UPS. > The packages are not marked. In contrast, even a coil cell comes in a box > saying it is batteries, not in transport if the package is damaged etc. So > Farnell follow all the rules. > > I contacted DHL once about a UK shipment of a battery powered item. That > was not a problem. > > If the box was much bigger than an OCXO, resistor oven, I don’t believe > heat would be a problem. > >> >> >> What's the hysteresis on a resistor? Is it really important to ship it >> powered up? > > > That I don’t know, but sometimes one does things as a challenge out of > interest, and to learn. It would be interesting to know if a resistor was > worth shipping powered up. > > Dave. > -- > Dr. David Kirkby, > _______________________________________________ > 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. _______________________________________________ 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.