In message , jimlux writes:
>One other thing to know about those USOs - they start about 1000 quartz
>blanks that are mounted in holders, and wind up with a couple dozen
>oscillators in dewars, and then run them all for a long time (many
>months) and watch them. 2 or 3 out of a batch
On 8/5/19 2:21 PM, Poul-Henning Kamp wrote:
In message , jimlux writes:
One other thing to know about those USOs - they start about 1000 quartz
blanks that are mounted in holders, and wind up with a couple dozen
oscillators in dewars, and then run them all for a long time (many
Hi
Keep in mind that all those designs date “way back” in terms of OCXO design.
The whole issue of pressure sensitivity really was not well understood /
accepted
until the mid 1990’s. Up to that point the whole “is it pressure or something
else”
thing was very much a hot topic.
In terms of
On 8/5/2019 3:30 AM, ew via time-nuts wrote:
Today most quality OCXO's are in a sealed can but three of the best HP10811,
Austron 1150 and OSA 8600/07 are not sealed. Austroon set screw hole has a
screw with an O ring. When you try to get the best out of them not part of a
loop you may have
Today most quality OCXO's are in a sealed can but three of the best HP10811,
Austron 1150 and OSA 8600/07 are not sealed. Austroon set screw hole has a
screw with an O ring. When you try to get the best out of them not part of a
loop you may have to consider compensation like with Rb's. Maybe
On Sat, 3 Aug 2019 14:22:22 + (UTC)
ew via time-nuts wrote:
> Are wee missing something. Reading Bill Slade post and old NASA
> attachments the attached plot to me was an eye opener. Our work
> has always been focused on Rb pressure compensation. Are we
> overlooking something. Has any one
Hi
You can run a controlled experiment where you simply change the pressure.
Crystals
are indeed pressure sensitive. It’s one of the reasons welded packages became
more
popular for OCXO’s ( welded crystal package inside a welded OCXO package means
less pressure change onto the crystal package).
How do we know the change is not due to humidity that happens to track
pressure?
Rick
On 8/3/2019 7:22 AM, ew via time-nuts wrote:
Are wee missing something. Reading Bill Slade post and old NASA attachments the
attached plot to me was an eye opener. Our work has always been focused on Rb
Are wee missing something. Reading Bill Slade post and old NASA attachments the
attached plot to me was an eye opener. Our work has always been focused on Rb
pressure compensation. Are we overlooking something. Has any one done some work
on this subject
Thanks Bert Kehren
517.pdf
