[time-nuts] Re: hydrogen rich environment and oscillators

[Bob Camp]

Hi

If we are off to a stabilized / vacuum environment, it’s a pretty good bet that there
will be multiple sources of leaks / outgassing / whatever to mess things up. You
will have a pump of some sort to deal with what’s going on. The better you can make
things, the smaller a pump you would need. It’s still a pump and under some sort
of servo control ….. loop back to “pressure sensor is out of whack” a week or two
ago :)

Bob

> On Dec 13, 2022, at 4:35 PM, Lux, Jim <jim at luxfamily.com> wrote:
> 
> On 12/13/22 1:24 PM, Poul-Henning Kamp wrote:
>> --------
>> Lux, Jim via time-nuts writes:
>> 
>>> Is there a cheap connector/feedthrough that can take 100 psi or so to be
>>> able to make measurements "in-situ"?
>> Use a window and optical transmission ?
>> 
> It's hard to get power in with optical transmission.
> 
> Say you have your favorite 10811 based GPSDO and you want to see how it's going to work in your diving bell loaded with heliox (with a coax cable to a floating buoy with the GNSS choke ring antenna) - but not really...
> 
> This is sort of different from the whole He, H2 question - but it raised the interesting question of operating devices at pressures other than room temp.  We've talked a lot on the list about schemes of varying complexity to thermally isolate an oscillator - well, putting it in even a partial vacuum might  be effective, one really wants to get the MFP to "bigger" than the gap between device and wall, so convection stops being an issue: then it's just radiation, but even if you pump down to, say, 1/100th bar, the bulk thermal conductivity will be (I think) 1/100th of what it is in "room air".
> 
> 
>