Chris wrote:
Where are you placing your antenna? I'm curious because you say the
choke ring helps. Is it close to the ground, near a building? What
might be the cause of the muiltipath that the choke ring is helping
with
I've been working with RF long enough not to expect easy answers when
Time-Nutters--
My workshop is surrounded by tall trees (70 to 80 ft). There
is no easy way to place my T-Bolt antenna above the tree-top
foliage. Since choke-ring antennas do not provide much benefit
for dealing with multi-path that originates from directly above
the antenna I have considered
Dear all,
for those interested, this is a nice summary of the cause of the wrong
OPERA measurement.
http://profmattstrassler.com/articles-and-posts/particle-physics-basics/neutrinos/neutrinos-faster-than-light/opera-what-went-wrong/
Regards,
Achim
Unless there is a real reason to open it don't. Weather seals can be a
devil to get sealed again. If it isn't seal moisture seeps in overtime and
destroys the unit.
Regards
Paul.
On Wed, Apr 11, 2012 at 1:57 AM, Chris Albertson
albertson.ch...@gmail.comwrote:
On Tue, Apr 10, 2012 at 10:02 PM,
The one I got there was a pretty good size hit where the two sections go
together. Otherwise I would not have. Before putting it together I did what
I use to do with optics. 24 hours in a desicant jar then filled with dry
nitrogen. All thanks to a friend who has access to such.
On Apr 11, 2012
I do like the optical isolation suggestion. While less than optimal,
perhaps the easiest solution is not to put the isolation between the t'bolt
and the antenna, but to put the isolation between the t'bolt and the
distribution amplifier.
For example, locate the antenna as suggested. Locate the
Hi all,
seeing this spec sheet:
http://www.saderet.co.uk/Admin/Datasheet/New%20antenna_spec.pdf
I was wondering why these antennas have so different GPS bandwidth.
Does the BW affect performance of a trimble thunderbolt for example?
Thanks in advance
Frank IZ8DWF
It seems to me (and I would be more than happy to hear any differing
opinions) that your GPS antenna only needs to be high enough to be able
to see a reasonable slice of sky. i.e. if your workshop were in the
middle of a circular clearing 80 feet in diameter in a forest with an 80
foot tree
Hi
The simple / stupid approach to the feed lines:
Put up the tower away from all structures
Put the antennas up on the tower.
Ground the tower well.
Run the feed lines down the tower
Ground the feeds both at the antenna and at the base of the tower
Put in a *good* arrestor at the base of the
On Wed, Apr 11, 2012 at 5:50 AM, Michael Baker mp...@clanbaker.org wrote:
I have thought about finding some way to bring the GPS
RF signal into my workshop via an optical fiber interface
and sacrifice the RF to optical fiber interface if lightning
strikes it in a treetop but have not found a
On Wed, Apr 11, 2012 at 7:19 AM, Bob Bownes bow...@gmail.com wrote:
The issue is that this treats the t'bolt as a sacrificial item. I would
contend that, at a cost of $80-90, you could spend far more time and effort
trying to isolate, amplify, correct, and bias the antenna than that is
worth.
Don't forget to tighten the fiber connectors and correct for the length of
the fiber or you'll be off by 60ns! ;)
On Wed, Apr 11, 2012 at 1:17 PM, Chris Albertson
albertson.ch...@gmail.comwrote:
On Wed, Apr 11, 2012 at 7:19 AM, Bob Bownes bow...@gmail.com wrote:
The issue is that this
On Wed, Apr 11, 2012 at 10:19:40AM -0400, Bob Bownes wrote:
I do like the optical isolation suggestion. While less than optimal,
perhaps the easiest solution is not to put the isolation between the t'bolt
and the antenna, but to put the isolation between the t'bolt and the
distribution
I suspect that would make the multipath problem even worse.
On Wed, Apr 11, 2012 at 4:06 PM, Andrea Baldoni erm1ea...@ermione.comwrote:
On Wed, Apr 11, 2012 at 10:19:40AM -0400, Bob Bownes wrote:
I do like the optical isolation suggestion. While less than optimal,
perhaps the easiest
On Wed, 11 Apr 2012 22:06:06 +0200
Andrea Baldoni erm1ea...@ermione.com wrote:
On Wed, Apr 11, 2012 at 10:19:40AM -0400, Bob Bownes wrote:
I do like the optical isolation suggestion. While less than optimal,
perhaps the easiest solution is not to put the isolation between the t'bolt
and
On Wed, 11 Apr 2012 16:37:42 +0200
francesco messineo francesco.messi...@gmail.com wrote:
seeing this spec sheet:
http://www.saderet.co.uk/Admin/Datasheet/New%20antenna_spec.pdf
I was wondering why these antennas have so different GPS bandwidth.
Does the BW affect performance of a
On Wed, 11 Apr 2012 22:06:06 +0200
Andrea Baldoni erm1ea...@ermione.com wrote:
I mean, rx external antenna - preamp - tx directional internal antenna -
big
air gap - rx directional internal antenna - receiver.
The preamp would not be so power hungry as the full thunderbolt and maybe
it
Hi
Putting the GPS on a fiber is fine, except you need a very large battery to
keep it running. As soon as you have a power line up to it, you are right
back to a metal conductor going to the wrong place(s).
Bob
-Original Message-
From: time-nuts-boun...@febo.com
On Wed, 11 Apr 2012 17:09:32 -0400
Bob Camp li...@rtty.us wrote:
Putting the GPS on a fiber is fine, except you need a very large battery to
keep it running. As soon as you have a power line up to it, you are right
back to a metal conductor going to the wrong place(s).
You are at the top list
This is a great discussion. I have been trying to decide the best compromise
between optimal reception and safety. Here in Boulder afternoon thunder
stormers are often a daily occurrence.
I cannot afford to learn from my mistakes on this one.
Thomas Knox
Date: Wed, 11 Apr 2012 22:37:06
Hi
If the antenna is no higher than your house, it's no more likely to get hit
than the house. If it's higher than the house by a few feet, the increase in
hit probability is vanishingly small. Provided the antenna is grounded as well
as your house power (as in *very* poorly) it's no more a
Original Message
Subject: WWVB test
From:John Lowe l...@boulder.nist.gov
Date:Wed, April 11, 2012 3:24 pm
To: Lowe, John P john.l...@nist.gov
--
The WWVB web page at NIST, here
http://www.nist.gov/pml/div688/grp40/wwvb.cfm
has a notice about another phase modulation test on
Sunday and Monday.
Dennis Ferguson
___
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
Thanks John
Will fire up the gear to see what happens and see what I might do on the
project.
On Wed, Apr 11, 2012 at 6:28 PM, J. Forster j...@quikus.com wrote:
Original Message
Subject: WWVB test
From:John Lowe
Turn on your Tracor 599J's and K's
*NOTICE***
*NIST Radio Station WWVB will be conducting a test of a phase modulation
scheme beginning at 0130 UTC, Sunday 15 April until 1400 UTC, Monday, 16
April 2012. Most WWVB-controlled clocks and watches will be not be
affected. Laboratory quality
Bob Bownes bownes at gmail.com
The issue is that this treats the t'bolt as a sacrificial item. I would
contend that, at a cost of $80-90, you could spend far more time and effort
trying to isolate, amplify, correct, and bias the antenna than that is
worth.
The conclusion may still be true
For this test coming up, I really want to get both my Spectracom devices, 8164
and 8170, going at the same time, if only to see that they both go crazy exactly
on time, yet I'm too lazy to install the second 8206 antenna in a decent
location. Do I need a power splitter to do this? Over at
I make GPS controlled clocks of various sorts and had been including cheap
Oncore receivers in them. In view of the inconvenience of needing a GPS
antenna feed for them I have decided to do something like this for local
distribution of the GPS sentence using little wireless modules such as the
Just the T and a DC block. 1/4 wave at 60 kHz is far, far longer than any
cable you have.
-John
==
For this test coming up, I really want to get both my Spectracom devices,
8164
and 8170, going at the same time, if only to see that they both go crazy
exactly
on time, yet
John hit the nail on the head. I have done that for both wwvb and loran c.
On Wed, Apr 11, 2012 at 9:47 PM, J. Forster j...@quikus.com wrote:
Just the T and a DC block. 1/4 wave at 60 kHz is far, far longer than any
cable you have.
-John
==
For this test coming up, I
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