Did you do any calculations to estimate the phase error (not the constant one), which will be introduced by certain components? A general question: what kind of signals do you want to compare/measure the phase? 10 MHz, 10 kHz, 1 pps, .....???? Square, sine-wave???

After I have the estimate I will pass it back to the group along with contact information for the fab shop so others can build copies. Problem with the 10509's on ebay is the people have them up with BIN's for insane money the last one I saw was in AS-IS condition was $695 I may be crazy but I am not stupid!

. >>>> >>>> Now I have not gone through the math to estimate performance >>>> compared to >>>> the traditional ZCD approach, but the complex multiply and average >>>> approach should be quite robust against noise, and is easily >>>> implemented in a DSP or FPGA. >>> >>> The time-difference between the two sampling points could be minimized >>> in such

. > > Some estimates for the effect of multipath on code phase receivers can > be found: > > http://bbcr.uwaterloo.ca/~wzhuang/papers/iee95_gps.pdf > > http://bbcr.uwaterloo.ca/%7Ewzhuang/papers/iee95_gps.pdf > > Since the better timing receivers use carrier phase smoothing of the > code phase timing, both the carrier phase and code phase performance of > the

Bob -----Original Message----- From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On Behalf Of EWKehren@aol.com Sent: Thursday, January 12, 2012 10:43 AM To: time-nuts@febo.com Subject: Re: [time-nuts] FE-5680A Mechanical Question Bringing out the C field in my estimation does not effect long or short term.

As the tone moves back and forth on the screen you can estimate what's going on. You need to do it same time each day and try to avoid sunrise / sunset issues. You want as consistent a propagation path as possible between you and the transmitter.

"The process described relies on the ability to estimate the resonator's quality factor. Experience indicates that the product voQ is a technical constant for piezoelectric quartz resonators, in the range from 1 x 10^11 to 2 x 10^13. As a matter of fact, the highest values are found in 5MHz resonators. ............."

I've got the Arduino code running that does the EOT, once a second (but using delay(1000) not the ISR), calculates the rate estimate, and accepts a sync command over the (emulated) serial port to set the time and date.

On Mon, Feb 24, 2014 at 7:44 AM, Bob Camp wrote: > Hi > > Ok, so 0.1 second at the sync point is indeed a reasonable estimate. If > that's all you need to deal with (you correct out the crystal offset one > way or the other) then: > > At 1 day you have 11.5 ppm accuracy.

DSP-ish software extracts the frequency data from the estimated zero crossings of the beat note. Doing it with a normal sound card isn’t very easy since the have issues (noise etc) below 20 Hz or so.