Re: [time-nuts] WWVB Dephaser Question

Paul and Bob, Thanks for the comments. I figured I wouldn't be able to get a 60 kHz signal anywhere near a WWVB receiver. I just wondered how bad the signal leakage from the divider IC would actually be. It is at a 5V logic level but I don't know if that means 5V of signal radiation. I was

[time-nuts] What's available in the way of DSP for new WWVB?

I assume it needs an antenna, front end, and D/A. What's available in the way of D/A that's good for 60KHz? Is the problem easier if the D/A box has external clocking? -- These are my opinions. I hate spam. ___ time-nuts mailing list --

Re: [time-nuts] WWVB Dephaser Question

Hello All, Are there any design details someplace regarding these massive antennas? Thanks, John AJ6BC On Thu, Oct 8, 2020, 19:27 paul swed wrote: > Hello to the group. > Ray as Bob mentions you are taking a 10s of uv signal to a logic level of > maybe 4V. > If the loop is any place close to

Re: [time-nuts] WWVB Dephaser Question

Hello to the group. Ray as Bob mentions you are taking a 10s of uv signal to a logic level of maybe 4V. If the loop is any place close to the divided down signal, it will oscillate. It would take incredible shielding to protect the receiver. Thats why you often see a solution that doubles to 120

Re: [time-nuts] WWVB Dephaser Question

Hi Some of the folks doing this are running pretty massive antennas. If you believe that the max signal from WWVB into your antenna is around 1 mV and accept the 5V p-p number, then you would need at least 74 db simply to have it not be equal to the transmit signal at max signal levels. You

Re: [time-nuts] WWVB Dephaser Question

Bob, I am using a ferrite rod antenna for the receiver. No outside antenna. Ray Original Message Subject: Re: [time-nuts] WWVB Dephaser Question From: Bob kb8tq Date: Thu, October 08, 2020 12:40 pm To: Discussion of precise time and frequency measurement Hi A lot depends

Re: [time-nuts] WWVB Dephaser Question

Hi A lot depends on your antenna setup. You can also swamp out the incoming WWVB signal……. Bob > On Oct 8, 2020, at 2:07 PM, > wrote: > > I have read several different articles where the WWVB phase shift is > eliminated by doubling the signal to 120 kHz. Several members of the > list have

[time-nuts] WWVB Dephaser Question

I have read several different articles where the WWVB phase shift is eliminated by doubling the signal to 120 kHz. Several members of the list have built these units. Assume I build a circuit to double the incoming signal and use a schmitt trigger to get a 120 kHz square wave. If I then divide

Re: [time-nuts] Aging 5065A ?

Hi It would be far easier to just use a (stock) 48 bit chip than to try to get something like that up and running ….. Keeping all the transitions “just right” would be tough. If you don’t do that, you have a major added source of spurs. Bob > On Oct 8, 2020, at 10:14 AM, Lester Veenstra via

[time-nuts] phase noise webinar from IEEE MTT-S

https://www.naylornetwork.com/mtt-mkt2019/email01.asp?projID=122255 There's a registration link at the above page. Low Phase Noise Signal Generation Utilising Oscillators, Resonators & Filters and Atomic Clocks Tuesday, October 13, 2020 - 12:00 PM Eastern Daylight Time Abstract:

Re: [time-nuts] Aging 5065A ?

I do not believe that is true. Only a longer D/A would result in a closer approximation to the desired waveform. A longer accumulator will result in being able to use a finer update rate but taking a longer time to do it. I built my first DDS in 1971 and studied their spurious very thoroughly

Re: [time-nuts] Aging 5065A ?

This I suspect is not original, but with respect for the need for 48 bit resolution, why not, say, a 24 bit, with reduced range such that it's steps are the same as what you would see with 48 bits, this stacked (Biased) on a fixed stable voltage in middle of expected control range. Fixed voltage

Re: [time-nuts] Aging 5065A ?

Hi You could also say that with a longer accumulator, you get a closer approximation to a desired waveform. If you compare the data sheets, the spur levels on the 48 bit parts ad9854.html ad9912.html

Re: [time-nuts] Experiment in lowering the TAPR TICC noise floor

On Mittwoch, 7. Oktober 2020 23:49:47 CEST Tom Van Baak wrote: > Matthias, > > Thanks for posting the raw data. You mention that both channels get the > same signal and so you expect a sqrt(2) improvement in noise > measurement. But consider... I didn't actually expect anything in particular. I