Re: [time-nuts] WWV Receivers

On Mon, Feb 6, 2017 at 11:27 PM, Hal Murray wrote: > > > esp. if one uses a Chinese $6.50 incl. shipping HF receiver off eBay; > > Could somebody give me a lesson in receivers appropriate for extracting > time > from WWV? > > Is $10 a realistic price? > Yes, this would

Re: [time-nuts] WWV Receivers

In message <20170207072741.b084f406...@ip-64-139-1-69.sjc.megapath.net>, Hal Murray writes: > >> esp. if one uses a Chinese $6.50 incl. shipping HF receiver off eBay; > >Could somebody give me a lesson in receivers appropriate for extracting time >from WWV? Somebody should do an SDR

[time-nuts] WWV Receivers

> esp. if one uses a Chinese $6.50 incl. shipping HF receiver off eBay; Could somebody give me a lesson in receivers appropriate for extracting time from WWV? Is $10 a realistic price? -- These are my opinions. I hate spam. ___ time-nuts

Re: [time-nuts] WWV receivers?

There is zero jitter through the SDR software because you can always buffer the output and then reclock it on output and all you have to deal with is a known fixed delay. If the samples are clocked in accurately that is all you need. Some audio interfaces have can have very good timing and run

Re: [time-nuts] WWV receivers?

No, no, no. The single chip in this case is an AFSK decoder. You still have to have an ordinary HF AM radio. > On Oct 29, 2016, at 11:21 AM, Chris Albertson > wrote: > > Are you sure the single chip receiver is not itself an SDR? Maybe using a > little 8-bit uP

Re: [time-nuts] WWV receivers?

On Sat, 29 Oct 2016 09:35:25 -0700 jimlux wrote: > > Should not be too high. If Jeff Sherman's and Robert Jörden's paper[1] > > is any indication, then the jitter should be dominated by the jitter > > of the ADC and its reference oscillator. So sub-ps, order of 100fs jitter

Re: [time-nuts] WWV receivers?

Are you sure the single chip receiver is not itself an SDR? Maybe using a little 8-bit uP inside? I don't know. In any case the jitter on the SDR depends on the sample rate clock. If you use a decent audio interface the clocks are not bad. A little 4-pin crystal oscillator controls the

Re: [time-nuts] WWV receivers?

On 10/29/16 4:49 AM, Attila Kinali wrote: On Fri, 28 Oct 2016 23:01:52 -0700 Hal Murray wrote: nsa...@kfu.com said: That single-chip version is going to have a *LOT* less (and less variable) latency than an SDR. Latency isn't an issue as long as it is known so that

Re: [time-nuts] WWV receivers?

Good thread. Thanks for the clue on the kiwiSDR. I went to the sites and lots of fun playing with the receivers. As an example hearing LORAN C in the Asia region. Certainly seems the receiver is pretty sensitive and capable. Went hunting for various low frequency timing signals such as JJY and the

Re: [time-nuts] WWV receivers?

Hi Let’s see…. WWV (not WWVB) gets here via a variety of propagation mechanisms that vary over the day. According to NIST (who probably know :) that puts a random timing variation of ~1 ms on the signal. Since some modes get me a signal and others don’t, there is no real reason to assume it is

Re: [time-nuts] WWV receivers?

In message <20161029134952.e60a2182e1f53844ec50b...@kinali.ch>, Attila Kinali writes: >> nsa...@kfu.com said: >> > That single-chip version is going to have a *LOT* less (and less variable) >> > latency than an SDR. >> >> Latency isn't an issue as long as it is known so that you can

Re: [time-nuts] WWV receivers?

On Fri, 28 Oct 2016 23:01:52 -0700 Hal Murray wrote: > nsa...@kfu.com said: > > That single-chip version is going to have a *LOT* less (and less variable) > > latency than an SDR. > > Latency isn't an issue as long as it is known so that you can correct for it. > >

Re: [time-nuts] WWV receivers?

nsa...@kfu.com said: > That single-chip version is going to have a *LOT* less (and less variable) > latency than an SDR. Latency isn't an issue as long as it is known so that you can correct for it. Has anybody measured the jitter through SDR and/or tried to reduce it? I'd expect that even

Re: [time-nuts] WWV receivers?

That single-chip version is going to have a *LOT* less (and less variable) latency than an SDR. > On Oct 27, 2016, at 12:20 AM, Poul-Henning Kamp wrote: > > > In message <5a002554-8d90-4c75-95da-21db45d61...@kfu.com>, Nick Sayer via > time- > nuts writes: > >>

Re: [time-nuts] WWV receivers?

In message <5a002554-8d90-4c75-95da-21db45d61...@kfu.com>, Nick Sayer via time- nuts writes: >If you’re in North America, a CHU receiver is a lot easier to make >than WWV/WWVH. The CHU timecode is just BEL 103 AFSK at 300 baud - >it was a one-chip solution 20 years ago when I made one in

Re: [time-nuts] WWV receivers?

I started to set up a WWV based reference clock. As for a receiver SDR is the best way to go but I built a tunnel front end. It is easy to do because it needs to only work at ne specify frequency so you can use a crystal filter with norrow bandwidth. The SDR receiver did direct conversion that

Re: [time-nuts] WWV receivers?

If you’re in North America, a CHU receiver is a lot easier to make than WWV/WWVH. The CHU timecode is just BEL 103 AFSK at 300 baud - it was a one-chip solution 20 years ago when I made one in college. On the software side, you’ll want a serial line discipline kernel module of some sort that

Re: [time-nuts] WWV receivers?

On 10/26/2016 02:54 AM, Hal Murray wrote: tsho...@gmail.com said: I'm all for a diversity of systems - putting all our eggs in the GPS basket seems unwise (and I maintain WWV receivers hooked to NTP at home!) What is available in the way of WWV receivers? Anybody got a summary handy? Yes,

[time-nuts] WWV receivers?

tsho...@gmail.com said: > I'm all for a diversity of systems - putting all our eggs in the GPS basket > seems unwise (and I maintain WWV receivers hooked to NTP at home!) What is available in the way of WWV receivers? Anybody got a summary handy? -- These are my opinions. I hate spam.