Lets be clear the 1 E-13 is a totally different project and does not relate
to the FE 5680 A. Yes most likely we will use the same universal
controller but with different code, same board. GPS crosses the 1 E-13 line at
10 seconds little more than a day. I whish it was just temperature a
Again we are talking past each other I am talking about temperature
compensation with the DDS that ideally should be removed. Those steps upset
any
loop.
Bert
In a message dated 6/24/2014 6:38:48 P.M. Eastern Daylight Time,
hol...@hotmail.com writes:
Check out the temperature control c
Hi
If:
1) You are after better than 1.0 x 10^-13 accuracy
2) You are getting 1 to 9x10^-9 at one second ADEV out of your GPS
3) You have a telecom Rb with 1 to 5x10^-10 temp coef over a 70C delta
4) Your Rb self heats 20 to 30C in still air
Here’s some math:
You will need at least 10,000 seco
On Tue, Jun 24, 2014 at 3:24 PM, Mark Sims wrote:
> ...
> However it is disappointing that no one has stepped up to tackle the
> temperature problem.
I can post what I have. It's a uP based PWM fan controller. It is a stand
alone device that does not know anything about the FE5680 but it woul
Check out the temperature control code in Lady Heather. It uses a nice PID
controller algorithm (from Warren Sarkison) to PWM modulate a fan to stabilize
the environment around the Tbolt. It can achieve millidegree range
stability... I have seen long term RMS values of the temperature plot le
bang-bang servos do depend on inherent low-pass filtering by the controlled
device.
Don
saidj...@aol.com
> Tom,
>
> airflow, or changes in airflow are typically much worse for ADEV than
> actual ambient temperature changes in still air.
>
> In still air for example a typical Eurocan DOCXO will hav
Tom,
airflow, or changes in airflow are typically much worse for ADEV than
actual ambient temperature changes in still air.
In still air for example a typical Eurocan DOCXO will have a case temp of
about 55C to 60C at 25C ambient.
Turn on any kind of significant airflow over that part and
> However it is disappointing that no one has stepped up to tackle the
> temperature problem. how many have looked at the temperature attachment and
> clicked on the N5TNL link. Let me make it clear that yes the GPSDO will work
> but
> there will be one or two orders of magnitude degradation
The response has been very positive such that a $ 45 kit is doable. Working
on getting at least two beta tests lined up.
However it is disappointing that no one has stepped up to tackle the
temperature problem. how many have looked at the temperature attachment and
clicked on the N5TNL link.
