[time-nuts] hm H Maser
bruce.griffiths at xtra.co.nz
Wed Jan 11 00:09:00 EST 2017
One could always use a cryo pump.
The following paper is a summary of the current state of the art for rubidium vapour frequency standards:http://www.euramet.org/Media/docs/Repository/A169/IND55/micalizio_02182015.pdf
On Wednesday, 11 January 2017 5:15 PM, Ole Petter Ronningen <opronningen at gmail.com> wrote:
Add to this ion-pumps (in the case of EFOS type masers 2 every ~2 years),
plus substantial tooling (turbomolecular vacuum pump, anyone?) to service
the thing - unless you want the manufacturer to do so..
On Tue, Jan 10, 2017 at 11:12 PM, Dr. David Kirkby (Kirkby Microwave Ltd) <
drkirkby at kirkbymicrowave.co.uk> wrote:
> On 10 January 2017 at 15:35, Ole Petter Rønningen <opronningen at gmail..com>
> > ... having said that, I for one think I'm with Bob on this one. The thing
> > about masers are that they are big. At least active masers. And they
> > require a substantial volume be kept at ultra high vacuum - which is not
> > trivial, especially not in a homeshop. The cavity needs to be kept at a
> > temperature stable to 0.001 degree C. With 4-5 magnetic shields. Add to
> > this costly pumps to keep the vacuum this low even if you succeed at
> > reaching that vacuum.. There's easily 1-2KUSD running cost per year just
> > keep the maser running.
> Looking at the Microsemi MHM 2010 Active Hydogen Maser data sheet, the
> maser has a peak power of 150 W and an operating power of 75 W. Based on a
> power consumption of 75 W, that is 657 kW hr / year of energy. I pay around
> £0.20 (GBP) per kW hr for electricity, so that's £131 (GBP) annually. I
> believe electricity is cheaper in the USA than here in the UK, but
> converting £131 (GBP) to USD, that's around $161/year in electricity.. So
> running costs don't seem to be an issue.
> But I must admit, the thought of spending a lot of time/money to build
> something I could have bought for a lot less with higher performance is not
> that attractive, although of course there would be a satisfaction from
> building it yourself.
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/
> and follow the instructions there.
time-nuts mailing list -- time-nuts at febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
More information about the time-nuts