Your imagination is broken.

There are lots more steps.  Most of them are very expensive.

--
These are my opinions.  I hate spam.

As far as I knew, the highest level steps actually on the market are
the Cesium beam clocks and the active hydrogen masers.  Are any
of the newer technologies available for purchase today?

Dana

On Mon, Nov 20, 2017 at 6:13 PM, Hal Murray hmurray@megapathdsl.net wrote:

I read up on the GPS L1/L2 and I think there is an L5.

And when you say “on the market” the real question is “can be purchased for 1/20th the price of new” like all the other re-purposed toys we buy,

Regards,

Jerry

Cost of a cesium clock can go from less than you pay for a pair of doxco‘s to many tens of thousands. I think 5071’s are in

Oops cat hit ‘send’

5071’s I’ve seen for as low as about 9k, but usually in the 15-30 range. I don’t want to know what they are new.

5061’s can be had for under $1000. If you are very lucky, under $500.

And once you have the standard, you need the counters. And other analysis tools...pretty soon your spouse will know you’ve gone off the deep end.

Anyone want an sr530 lock in amplifier that eats fuses and voltage regulators?

Bob

Thanks, Bob, I’ll have to start looking now.

I’ve been looking for other counters, I only have 5371a x 2 and 5335a x 2 and some other TeK modules.  I went back and was reading the time-nut counter thread from 2008 and will have to keep looking for something I want to afford.

Tonight I was plotting one of the rubidium modules Gilbert gave me against my Lucent GPSDO.  I was just measuring frequency and I had some glitches that I think are from triggering.  The stdev on some 2 hours runs were .0017 with a frequency of 9,999,999.956 average.  I have a new power supply coming tomorrow and I’ll be able to move it into a room where I can try to tweak it closer to 10M.

The Adev plot of the Frequency was sort of weird looking, sort of like a flattened “U” with the dip around 10E-15.  I would have thought it should be more like a typical downward sloping line. I’ll have to read up and see what this indicates.

So much to learn, so little time.

Thanks for all the pointers. Someone should write a book, “Time-nuttery for dummies”.

Jerry

On Mon, 20 Nov 2017 20:50:17 -0800
Jerry Hancock jerry@hanler.com wrote:

for your rainy Sunday reading:

http://www.navipedia.net/index.php/GPS_Signal_Plan
http://www.navipedia.net/index.php/Galileo_Signal_Plan
http://www.navipedia.net/index.php/GLONASS_Signal_Plan
http://www.navipedia.net/index.php/BeiDou_Signal_Plan

And because everyone likes large, colorful graphs:
http://www.insidegnss.com/auto/popupimage/GLONASS%20spectrum%200408.jpg

Yes, it's getting crowded.

		Attila Kinali

--
It is upon moral qualities that a society is ultimately founded. All
the prosperity and technological sophistication in the world is of no
use without that foundation.
-- Miss Matheson, The Diamond Age, Neil Stephenson

Hi

Cesiums (that may be on their last legs or maybe not) are pretty common
in the market. Prices vary, but generally are < $4,000. Bought new they are
in the $70,000 range.  Masers show up much less often. Price wise … that
depends. The cheapest working unit I have heard of was in the $30,000 range.
New, you see some with $150,000 price tags on them.

Fountain standards for the commercial market have been a “real soon now”
sort of thing since the 1980’s. I have yet to see anybody selling one (as opposed
to building it in a lab and using it). Yes, there always has been a lot of talk.
There don’t seem to be any shipments….

State of the art Ion standards are something you lock up a building full of very
smart people for a good chunk of their career to come up with. Unless you have
a budget funded by a rich uncle (or something similar)… don’t go there.

That sounds very discouraging. Actually it’s not. There is no real need to have
a “best in the world” fountain or ion standard. One that simply works probably
would be fine by any of us. The same is true of the Maser. Putting in a few years
of work to get one up and running might be an ok thing if the price was right.

=====

The bigger point is: what do you do / what can you do with this stuff?

As you scale up the standard, the bench that goes around it probably scales
as well. The counter that was fine back when you only had a partially working
OCXO as a standard may not be “good enough” with your maser. Watching
the second tick on your WWVB clock may no longer be “interesting” you may
want to plot signals from far away stars ….

It just keeps getting worse !!!

Bob