At 06:58 AM 6/24/2003 -0400, you wrote:
At 12:49 PM 6/23/2003 -0400, you wrote:
>I received my HP Z3801 last week. To keep things on topic, the intent is to
>use it as an external reference for my RX340.
It's RF related and that's close enought for me!!!
As one of those 'radio guys' at the tower sites, I see these GPS antennas
frequently. Paging services use them for syncronization of their
transmitters. Cell carriers use them for E911 calls and many broadcast
stations use them for their frequency standard.
CDMA sites also use them for frequency standard -- for coordinating handover
and the frequency hopping? Dunno. But that's where these come from. To
those who haven't already set up your GPS, before you reset it, ask for a
status to get the coordinates of where it was last installed.
30' feedlines are common
and 50' runs are not uncommon. For shorter (<25') runs 1/4" hard line is
the norm and out to 50' 3/8" is often used. As with any tower/cell site
installation, a Polyphaser lightning protection device is in line at the
shack entrance.
Remember to get a Polyphaser that passes DC so that the preamp gets power
from the GPS. The more common (to ham users) Polyphasers block DC. There
are specific narrow-band ones for GPS, though, IIRC.
Eric
--
Eric F. Richards
efricha@dimensional.com
"The weird part is that I can feel productive even when I'm doomed."
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