[amsat-bb] Re: expections
domenico.i8cvs at tin.it
Mon May 28 06:44:53 PDT 2012
To answere your question it is necessary to know the following data:
1) Gain in dBi and polarization of your antenna UHF Ringo ranger set.
2) Noise Figure NF in dB and gain in dB of your LNB High Sierra
Microwave 432M7 downconverter.
3) Value in MHz of the IF of your 432M7 downconverter.
Having the above data it is possible to compute if it necessary or not
to put a 70 cm Low Noise preamplifier between the antenna and the
input of downconverter or to use an antenna with greater gain but
rotatable in Azimuth and Elevation.
BTW not rotatable antennas like the "eggbeater style" or your UHF
"Ringo ranger set" have poor performance for LEO satellite operation
if compared with a simple 10 dBi horizontally polarized Yagi antenna
rotatable only in Azimuth and fixed Elevation of 20 degrees as often
recommended for LEO satellites by Bob, WB4APR on AMSAT-BB
----- Original Message -----
From: "Alan Beck" <becka at eastlink.ca>
To: <amsat-bb at amsat.org>
Sent: Monday, May 28, 2012 1:53 PM
Subject: [amsat-bb] expections
> Currently I have my LNBlock downconverter mounted at the antenna.
> It is a High Sierra Microwave 432M7.
> The antenna is a Uhf Ringo ranger set at the boiiom end of the band.
> It is 25 feet up right now.
> So, how do I realize more signal level?
> Using my FT-950, both preamps on I can hear signals well.
> I have about 75 feet of RG-8X coax at the output of the converter to my
> The test paper shows 25 DB gain. I expect this has to be on the UHF side.
> I am thinking of a "eggbeater style" antenna to start with and then some
hieght for that.
> Passes are doing well to the horizon.
> Looking forward to feedback.
> Sent via AMSAT-BB at amsat.org. Opinions expressed are those of the author.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
More information about the AMSAT-BB