kb8tq@n1k.org said:
A KS-24361 says:
Predict 394.1 us/initial 24 hrs
That would suggest the unit is unlocked. It should be below 10 us. Just as
with the 3801, the estimate is a bit fuzzy. You should be able to see issues
in the data on the Z3809/Z3810.
It says it is locked and has been locked for days.
Locked to GPS TFOM 3 FFOM 0
I used this as a learning exercise for my new TICC. Something is clearly
fishy.
The reference for the TICC is the crystal in a HP 5334B with the good-crystal
option. It's not calibrated, but there isn't any GPS logic to jerk it
around. I assume the swing is due to temperature. I corrected the slope of
the graph by hand.
Here is a day+ of data:
http://users.megapathdsl.net/~hmurray/time-nuts/TICC/TICC-KS.png
Here is a zoomed in chunk:
http://users.megapathdsl.net/~hmurray/time-nuts/TICC/TICC-KS-2.png
--
These are my opinions. I hate spam.
Hi
There isn’t much you can really see on a GPSDO comparing it to a normal OCXO.
The OCXO simply is not accurate enough. You need something like a Cs standard,
a different GPSDO, or a good Rb for the reference. (Yes, if you have a hydrogen
maser, you can use that ….).
First thing to check is the DAC readings on the unit ….
Bob
On Apr 15, 2018, at 6:59 AM, Hal Murray hmurray@megapathdsl.net wrote:
kb8tq@n1k.org said:
A KS-24361 says:
Predict 394.1 us/initial 24 hrs
That would suggest the unit is unlocked. It should be below 10 us. Just as
with the 3801, the estimate is a bit fuzzy. You should be able to see issues
in the data on the Z3809/Z3810.
It says it is locked and has been locked for days.
Locked to GPS TFOM 3 FFOM 0
I used this as a learning exercise for my new TICC. Something is clearly
fishy.
The reference for the TICC is the crystal in a HP 5334B with the good-crystal
option. It's not calibrated, but there isn't any GPS logic to jerk it
around. I assume the swing is due to temperature. I corrected the slope of
the graph by hand.
Here is a day+ of data:
http://users.megapathdsl.net/~hmurray/time-nuts/TICC/TICC-KS.png
Here is a zoomed in chunk:
http://users.megapathdsl.net/~hmurray/time-nuts/TICC/TICC-KS-2.png
--
These are my opinions. I hate spam.