GPS Antenna
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful
spec on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I
figure that splitters are just a transformers and will not pass DC to
power the antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their
house with no protection from lightening? Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida
--
Chris Albertson
Redondo Beach, California
Re item 2 I have had success using satellite tv splitters that provide for dc pass thru as gps signal splitters. I can't argue with the price and being able to buy them at home depot.
Re item 3 I ground the mast for gps antenna, and the shield of the feed line. (I already have ground system for various radio antennas.) If I lived in an area with lots of lightning i'd take more precautions. I've also bonded the Antenna grounds to the electrical service ground, which may or may not be a code requirement where you live. (Disclaimer don't take this message as advice.)
Sent from my iPad
On 2010-12-30, at 3:25 PM, Chris Albertson albertson.chris@gmail.com wrote:
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful
spec on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I
figure that splitters are just a transformers and will not pass DC to
power the antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their
house with no protection from lightening? Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida
--
Chris Albertson
Redondo Beach, California
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and follow the instructions there.
Hi Chris,
Re: 1)
The Tbolt is a bit 'deaf' by modern standards and ideally needs a 26dB
aerial for best performance. I could only source an 18dB aerial when I
initially installed my Tbolt and the lower signal level can be seen when
running Lady Heather.
The 26dB units are available from time to time on ebay, but check the
specifications carefully because the lower gain versions look the same -
a bit like a white plastic easter egg!
Regards,
David
On 30/12/2010 23:25, Chris Albertson wrote:
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful
spec on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I
figure that splitters are just a transformers and will not pass DC to
power the antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their
house with no protection from lightening? Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida
The thunder bolt specs an antenna to use with it. I don't have the manual with me, but it is more like 34db. I found a HAG-240 marine antenna in a surplus shop for $15.
-----Original Message-----
From: Chris Albertson albertson.chris@gmail.com
Sender: time-nuts-bounces@febo.com
Date: Thu, 30 Dec 2010 15:25:46
To: Discussion of precise time and frequency measurementtime-nuts@febo.com
Reply-To: Discussion of precise time and frequency measurement
time-nuts@febo.com
Subject: [time-nuts] GPS Antenna
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful
spec on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I
figure that splitters are just a transformers and will not pass DC to
power the antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their
house with no protection from lightening? Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Hi all,
I use a Symmetricom 58532A, they have a gain of 30 - 38dBi. Just what
you need for a deaf Tbolt on the end of a long coax run :)
You can buy them off eBay for ~$30 each
http://cgi.ebay.com/Symmetricom-58532A-N-type-female-GPS-antenna-antenne-/230568432072
regards
Tim
--
VK2XTT :: QF56if :: BMARC :: WIA :: AMSAT-VK :: AMSAT
Chris,
There are several Symmetricom splitters available, including 1:2 and 1:4
that can be had, on occasion, 'on the Bay' that work well with the TBolt,
although I use one of the 1:4 units with a TBolt, a Z3816A, a Z3805A, and
that leaves a 'spare' for any other project I am working on, that requires
both the TBolt and a Z3816A powered on to function normally. The ones I use
are the 58535A and the 58536A. There are several listed now, including this
one 350426342961 (no connection to the seller).
IIRCC, someone on the list had offered some for sale at very reasonable
prices in the past. Perhaps he is 'listening' or you can find him by
searching the archives.
I have my antenna (like this one 290469118397 no connection to seller except
a satisfied customer for other items) mounted on the corner of my workshop,
lower than the rest of the house, under some trees (not the best location by
any means) but out of the way of the lightning here in FL and it feeds the
splitter (no lightning protection) which feeds the receivers and works well.
I have not performed any 'formal' measurements of the stability of the 10
MHz or 1 PPS signals though. That's on one of my many 'back burners'.
Hope this helps and good luck.
Happy New Year to you and all on the list. Thanks again to all on the list
for all your help to me in the past.
Joe
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Chris Albertson
Sent: Thursday, December 30, 2010 5:26 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] GPS Antenna
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful spec
on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I figure
that splitters are just a transformers and will not pass DC to power the
antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their house
with no protection from lightening? Maybe a GPS antenna is a small target
compared to a 100 foot wire antenna in Florida
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
This discussion prompted me to remind list members that I still have some of
the subject smart GPS splitters available. These are brand new in original
wrapping. The pricing is:
1 58535A $35 plus $ 4.95 priority flat rate shipping
2 58535A $65 plus $ 4.95 priority flat rate shipping
4 58535A $120 plus $10.70 priority flat rate shipping
I am not certain, but, it is possible that USPS flat rate priority may go up
in 2011. BTW, flat rate is not that much more to other countries, and, I do
not mind filing out the customs forms.
Best to all in 2011. Regards - Mike
Mike B. Feher, EOZ Inc.
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960 office
908-902-3831 cell
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Chris Albertson
Sent: Thursday, December 30, 2010 6:26 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] GPS Antenna
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful
spec on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I
figure that splitters are just a transformers and will not pass DC to
power the antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their
house with no protection from lightening? Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida
--
Chris Albertson
Redondo Beach, California
Definately nice ways to go. However if this is a hobby then TV RF splitters
and satellite LNB IF line amps (LNBs IFs are .9-1.5 Ghz) also work very
well. I picked up the line drivers for $2 at a typical old stock store and
splitters to 2 Ghz for $1. Measured them and they are pretty good. But the
real test is inline and every thing seems to work well. I have 3-4 rcvrs
hooked up.
Regards
Paul
WB8TSL
On Thu, Dec 30, 2010 at 10:45 PM, J. L. Trantham jltran@att.net wrote:
Chris,
There are several Symmetricom splitters available, including 1:2 and 1:4
that can be had, on occasion, 'on the Bay' that work well with the TBolt,
although I use one of the 1:4 units with a TBolt, a Z3816A, a Z3805A, and
that leaves a 'spare' for any other project I am working on, that requires
both the TBolt and a Z3816A powered on to function normally. The ones I
use
are the 58535A and the 58536A. There are several listed now, including
this
one 350426342961 (no connection to the seller).
IIRCC, someone on the list had offered some for sale at very reasonable
prices in the past. Perhaps he is 'listening' or you can find him by
searching the archives.
I have my antenna (like this one 290469118397 no connection to seller
except
a satisfied customer for other items) mounted on the corner of my workshop,
lower than the rest of the house, under some trees (not the best location
by
any means) but out of the way of the lightning here in FL and it feeds the
splitter (no lightning protection) which feeds the receivers and works
well.
I have not performed any 'formal' measurements of the stability of the 10
MHz or 1 PPS signals though. That's on one of my many 'back burners'.
Hope this helps and good luck.
Happy New Year to you and all on the list. Thanks again to all on the list
for all your help to me in the past.
Joe
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Chris Albertson
Sent: Thursday, December 30, 2010 5:26 PM
To: Discussion of precise time and frequency measurement
Subject: [time-nuts] GPS Antenna
A few questions about GPS antenna....
-
I read the Thunderbolt user manual and did not find any meaningful spec
on the antenna except that it is amplified and uses DC power in
the coax. What signal level is the Thunderbolt expecting? oes it
want a 24dB antenna or more or much less? -
I want to feed two GPS units with one roof mounted antenna. I figure
that splitters are just a transformers and will not pass DC to power the
antenna. There must be an easy way around this. -
Do people really run coax straight from a GPS antenna into their house
with no protection from lightening? Maybe a GPS antenna is a small target
compared to a 100 foot wire antenna in Florida
--
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
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Chris said:
- Do people really run coax straight from a GPS antenna into their
house with no protection from lightening? Maybe a GPS antenna is a
small target compared to a 100 foot wire antenna in Florida
Chris, I'm in Orlando, the lightning capitol of the entire world. Here, *
nothing* is a small target. Anyone who fails to install lightning
protection on a GPS antenna will, sooner or later, buy a new GPS...or a new
room full of gear...or a new house. Smart hams down here use wireless
routers or optical bridges, serious whole-house surge protectors (Siemans is
my choice), equally serious power conditioners (Brick Wall is my choice),
isolated UPS systems, antenna grounding switches, and star ground systems.
We laugh when the cable company tells us their lines are surge protected and
install additional equipment after their technicians roll away And we still
get damage on an occasional basis.
Just a fact of life in Florida.
Tii Network Technologies makes a coaxial surge protector designed for cable
systems but suitable for GPS antennas if you will put up with F
connectors. They work fine for me but I have a very short run.
Bill
Oh, before someone grumbles, I have no connection with Siemans or Brick Wall
or Tii. I just use their gear.
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