Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-05 Thread Bob Camp
Hi For NTP grade timing, there are still a lot of broadcast sources out there. You *do* need to be careful about propagation and when to (not) use them during the day. Focusing effort on that part of it is probably more useful than waiting for funding to appear for eLoran…. Bob > On Feb 4,

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-04 Thread Ruslan Nabioullin
On 02/03/2017 10:02 AM, paul swed wrote: Ruslan NH will be easy to pick it up. The core frequency is 3 Cesiums in a cluster. As for time transfer it can but its really a pain in the backend and that information is indeed in the data channel. So make us jealous with your CS and RBs. :-) I am down

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-04 Thread Bob Camp
Hi The ground wave (hopefully) travels a shorter path. The gotcha comes in when the phase shift is 180 degrees and you start nulling things out. That will play havoc on the “stuff” that works out the envelope shape for detecting the third pulse. Again, I didn’t design a from scratch receiver

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-04 Thread Hal Murray
kb...@n1k.org said: > If I had not already calibrated the local standard against a nearby chain … > no way to figure out which data was correct. Isn't the ground wave shorter and hence gets there sooner? Couldn't you use that to calibrate an uncalibrated local standard? -- These are my

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-04 Thread Bob Camp
Hi The Russian system runs an incompatible pulse format. A “normal” Loran receiver pretty much pukes when you try to tune to the Russian chains. It also is a bit unclear just how stable their system is timing wise. For timing you *need* ground wave. Anything that is more than 1,000 miles away

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-04 Thread Poul-Henning Kamp
In message , Ruslan Nabioullin writes: >On 02/03/2017 09:53 AM, Bob Camp wrote: >> You can also pick up the Russian system >> that runs on the same frequency. "Chayka" on GRI 8000 is almost useless, I'm told this is so even in Russia,

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-04 Thread Ruslan Nabioullin
On 02/03/2017 09:53 AM, Bob Camp wrote: With reasonable gear, you can pick up the European Loran chains in the US on a regular basis. You can also pick up the Russian system that runs on the same frequency. The gotcha there is that you are looking at “skywave” rather than “ground wave” signals

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Poul-Henning Kamp
In message <20170203214011.76e59406...@ip-64-139-1-69.sjc.megapath.net>, Hal Murray writes: >What does the spectrum look like? Is that even a reasonable question for >that sort of signal? Look here for some background: http://phk.freebsd.dk/loran-c In particular:

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Bob Camp
Hi The spectrum is about what you would expect from a bunch of short pulses. http://phk.freebsd.dk/loran-c/theoretical_spectrum/ Bob > On Feb 3, 2017, at 4:40 PM, Hal Murray wrote: > > > kb...@n1k.org said: >> the signal shows up over many 10’s of KHz of bandwidth

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Hal Murray
kb...@n1k.org said: > the signal shows up over many 10’s of KHz of bandwidth each side of 100 > KHz. What does the spectrum look like? Is that even a reasonable question for that sort of signal? How well do typical old/analog spectrum analyzers work on that sort of signal? (as compared

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Poul-Henning Kamp
In message <589490f1.4090...@erols.com>, Chuck Harris writes: >All Loran C signals are transmitted at precisely 100.0... KHz. Actually, they're not. The envelope changes the frequency in rather interesting ways. I used to have a plot of it, but it seems to have disappeared into my

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Poul-Henning Kamp
In message , paul swed writes: >John absolutely 1 frequency 100 KHz. The repetition rate is 89700 us. Its >pulse and you need about +-15KHz BW. If listening its just a ticking sound. Instead of your SDR it might be

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread paul swed
John absolutely 1 frequency 100 KHz. The repetition rate is 89700 us. Its pulse and you need about +-15KHz BW. If listening its just a ticking sound. Ruslan NH will be easy to pick it up. The core frequency is 3 Cesiums in a cluster. As for time transfer it can but its really a pain in the backend

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Bill Riches
100 khz. 73, Bill, WA2DVU -Original Message- From: time-nuts [mailto:time-nuts-boun...@febo.com] On Behalf Of John Marvin Sent: Friday, February 3, 2017 1:21 AM To: time-nuts@febo.com Subject: Re: [time-nuts] eLoran test 6 Feb for almost 2 months I don't have a Loran receiver, and I

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Bob Camp
Hi Loran C is a pulse based system. All transmitters world wide run on the same 100 KHz frequency. The thing that distinguishes one transmission from another is the repetition rate of the signal. If you have a spectrum analyzer and hook up a piece of wire near one of the transmitters, the

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Chuck Harris
All Loran C signals are transmitted at precisely 100.0... KHz. They are a pulse signal system, where each member of the chain uses a different repetition rate to time the placement of its pulses. The repetition rates are designed so that they pulses from any two chains are not coincident,

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread Ruslan Nabioullin
On 02/02/2017 09:47 PM, paul swed wrote: Ruslan, Seems to be backward compatible. Yes. All of my stuff works austrons and SRS 700. Whats your location? The transmitter is in NJ and I am near Boston. So somewhat close for me. My antenna is the standard boat preamp and whip antenna. 6 foot off the

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-03 Thread John Marvin
I don't have a Loran receiver, and I live in Colorado. But I'd still like to check late at night to see if I can see a signal on my SDR receiver. I tried looking at old posts, and did some research online, but the best I can tell is that Loran C (and I assume eLoran) is transmitted at around

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-02 Thread paul swed
Ruslan, Seems to be backward compatible. Yes. All of my stuff works austrons and SRS 700. Whats your location? The transmitter is in NJ and I am near Boston. So somewhat close for me. My antenna is the standard boat preamp and whip antenna. 6 foot off the ground. Regards Paul WB8TSL On Thu, Feb

Re: [time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-02 Thread Ruslan Nabioullin
On 02/02/2017 01:59 PM, paul swed wrote: Well this is nice almost a 2 month long test. So if you thought about seeing if you could receive eLoran on your Loran C receiver this is a good opportunity. With respect to the data channel pretty sure none of the receivers we have know or care about it.

[time-nuts] eLoran test 6 Feb for almost 2 months

2017-02-02 Thread paul swed
Well this is nice almost a 2 month long test. So if you thought about seeing if you could receive eLoran on your Loran C receiver this is a good opportunity. With respect to the data channel pretty sure none of the receivers we have know or care about it. The Wildwood, NJ eLoran transmitter will