Hiya,
Thank you for all the thoughtful replies on list and a couple received
off list too.
There is at least one VLF station in north western Australia which I
think will be close enough to at least warrant the experiments, so will
get myself set up with a loop antenna and suitable SDR and
Whit Griffith N5SU was the Chief Radio Scientist (or some similar title) for
Continental Electronics in the 1980's in Dallas. In around 1990 Whit gave a
slide show presentation to a Dallas Amateur Radio Club meeting at the National
Communications Museum, a project at the Dallas Communication
Hi
Back in the day, if you hung out for a while in the lobby at Continental
Electronics, you would notice a
model of an old style transmitter over by one wall. Go over and look a it for a
a while and all the usual
parts were there. Couple of big tubes, big matching coil insulators here and
Hi,
Thought I'd see if anyone has some "dead" FE 5650A or FE 5680A
(the rev B). I'm looking for a few of the synthesizer modules
for some experiments. I don't need the rest of the unit.
It's the board with the two tiny pushbuttons on it. See PIX.
Willing to pay, but not too much!
Cheers,
On 8/7/20 4:13 PM, Bill Byrom wrote:
See this 1961 IRE paper at the NIST website:
https://tf.nist.gov/general/pdf/2303.pdf
IRE merged with AIEE in 1963 to form IEEE.
Figure 7 shows the calculated amplitude transfer of the ground wave signal vs
frequency and distance. Note that for 100 kHz
See this 1961 IRE paper at the NIST website:
https://tf.nist.gov/general/pdf/2303.pdf
IRE merged with AIEE in 1963 to form IEEE.
Figure 7 shows the calculated amplitude transfer of the ground wave signal vs
frequency and distance. Note that for 100 kHz signals, the ground wave signal
is
Exactly and at night you have groundwave and skywave. In reality both exist
all of the time its just the strength changes. This is why LORAN C radios
have ability to reduce the effects of skywave. It has to do with the
structure of teh transmitted signal.
Paul
On Fri, Aug 7, 2020 at 6:25 PM
Gilles Clement writes:
> Would’nt 100khz carrier propagate mostly by ground wave (during day time) ?
> So following earth curvature ?
First: It's not really a 100kHz carrier, it is a 85-115kHz spread-spectrum
signal.
Second: Yes, and that is exactly the point.
--
Poul-Henning Kamp
Would’nt 100khz carrier propagate mostly by ground wave (during day time) ? So
following earth curvature ?
Gilles.
> Le 7 août 2020 à 21:34, paul swed a écrit :
>
> Taka
> Yes it does. More ionosphere than air. It would be skywave or indirect
> path. I mentioned that earlier.
> Now silly
John,
It's common to see either 4 or 5 digit numbering, where "chain 9940" and
"GRI of 99400 µs" are equivalent. The former is short-hand; the latter
uses proper SI units. If that looks odd, see some GRI examples:
"FS700 LORAN-C frequency standard"
John it did indeed go to 1us not sure when. Definity a requirement in
Europe.
But the Austrons and SRS demand it. Not sure the old Austron 2000 did.
But that was a pain to use. Actually useful to have a scope while setting
it up.
I also designed my first LORAN C receiver but for frequency locking
When I designed and built my LORAN-C receiver, for navigation not precise time,
it was my understanding that all GRI's (Group Repetition Intervals) were
expressed as four digit numbers. I designed my receiver accordingly. The number
was the repetition time in units of 10 microsecs. This is the
Taka
Yes it does. More ionosphere than air. It would be skywave or indirect
path. I mentioned that earlier.
Now silly thought would a huge antenna work especially if you are at the
antipode. Further would it be gray line propagation.
Thats just silly talk. But something to think about.
Regards
Hi
The idea is that over a limited coverage area, you can supply “correction” info
to reduce the impact
of propagation. GPS (and other GNSS systems) do this sort of thing already.
Just as with GNSS, the
corrections will (likely) only get you just so far.
Bob
> On Aug 7, 2020, at 11:32 AM,
Wouldn't such a long distance propagation result in less precision? The signal
will have to go through distance through air which isn't constant in dialectic
values. Wouldn't it be problematic for level of accuracy we pursue?
---
(Mr.) Taka Kamiya
KB4EMF /
Hi
> On Aug 6, 2020, at 9:38 PM, Forrest Christian (List Account)
> wrote:
>
> I probably need to clarify where I'm coming from in relation to my previous
> message.
>
> I have a fair bit of background in dealing with using GPS clock sources for
> synchronization at communication sites.
I believe South Korea is indeed building new eLORAN chains. I have seen
mention of it.
With respect to distance In the US I could occasionally receive the
European West chain at night and in the winter. Thats about 3200 miles. It
would also be by skywave so that deteriorates accuracy.
Regards
Paul
Are not South Korea are building one? new eLoran chain? Are they transmitting?
But don’t underestimate the distances from south east Asia to the far side of
Australia.
/Björn
Sent from my iPhone
> On 7 Aug 2020, at 10:24, Poul-Henning Kamp wrote:
>
>
> Hugh Blemings writes:
>
Hugh Blemings writes:
> Been following this thread with the usual mixture of joy, awe and wonder
> (truly!) - fantastic stuff :)
>
> My read of the situation is that there is next to no chance of receiving
> any meaningful signal at the VLF frequencies in question down here in
>
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