Until I move into the house I'm getting I'm in a rental condo where absolutely
no antennas are permitted. It's a building and I'm on the 4th floor so have
done things like ran a very thin wire out one window to a far one, a wire with a
weight nearly to the ground, a rather long wire (#26 stranded copperweld) to a
far fence (at night), the Tbolt antenna clamped to my railing, and a mil type
multisection vertical clamped to said railing (also at night). Been here for a
couple of years and nobody's said a word, yet I've seen letters go out to
everyone about christmas decorations that were visible through windows. The
roof is locked but if I were to live here longer I would find a way up there and
feed a coax or three through the 1" PVC conduit which carries the thermostat
cable up to the A/C unit up there for my unit and have a blast with it.
Peter
On 9/27/2012 7:20 PM, Bob Camp wrote:
Hi
At least in my back yard, a 6' tall tripod would be very noticeable from a
number of directions. There are many others in similar situations. If I were to
interpret the restrictions literally as written, an antenna that was inside the
house, but visible through an open window is also a violation.
Bob
On Sep 27, 2012, at 7:11 PM, johncr...@aol.com wrote:
Various comments -
Hal mentioned SNR for the scheme I suggested. A PLL can be a coherent
demodulator of arbitrary
bandwidth. Thus the PLL at the output of the doubler can have a small bandwidth
since at that point
there is no PSK, it having been removed by the doubler. So given a stable VCXO
you can probably get down
to 1 Hz and thereby achieve a good SNR. There is a lot of stuff out there on
phase tracking receivers
that do exactly that. You know the frequency so the loop does not have to
search far and the BW can be increased
for acquisition and closed up for tracking.
On writing reams of code - my point was that it is not required to used the
admittedly more powerful software
techniques to do this job - I noted that one reason to write reams of code is
for the fun of it, this is after all
a hobby.
GPS Antenna Siting -
Lets not make this so hard. Mine is at 6 ft elevation and is blocked to an
elevation angle of 20 to 30 degrees by a house
within 15 ft and a forest of trees. I have room and no restrictions but I also
have severe thunderstorms - so the house
plays lightning protect for the antenna. My T bolt tracks a Rb to better than
1e-12 over 24 hours with no serious 10 MHz phase bumps
as plotted on a strip chart recorder.
Sooooo -
Put your antenna at 6 ft in back yard. Start out on a photo tripod - who is
gonna notice?
set up a t bolt at EL=5 AMU=0 Damping = 1.2 and Time Constant = 100 sec.
get the t bolt manual
get Tbolt monitor
get Lady Heather and read all that stuff.
Run Lady Heather antenna survey (command SAS) for at least two days - you get
a map of signal level in dBc vs elevation
Reset the Tbolt elevation mask to reject anything that is shown as blocked
using the signal
level map. Likewise experiment with the AMU setting to reject the weak = poor
signals. Mine works good
with AMU all the way up to 10 as fewer good satellites are better than lots of
weak ones.
The satellites are in high orbits so masking those below 25 degrees is OK and
the AMU sets the acceptable signal
level - at AMU 10 my setup throws out those below about 40 dBc - the strong
guys go up to 50. This is a function
of you antenna performance so some experimentation is required.
-73 john k6iql
_______________________________________________
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.
_______________________________________________
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.
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1427 / Virus Database: 2441/5295 - Release Date: 09/27/12
_______________________________________________
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.
