[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

RE: TH-F6 and UHF SSB



On Tue, 26 Feb 2002, Steve wrote:

> I modeled a 19" vertical using NEC and it does seem to workout pretty
> well for satellite use.
> The main lobe is at about 50 deg. and looks pretty broad. The only down
> side was the deep null straight up (from around 80 deg. or so). Not much
> gain but it doesn't require a rotator either.
> I'll have to try it sometime.

But you will notice that the probabiliy of ANY given satellite being
above even 60 degrees is less than 2 % of the time... And above 80
degreees is much less than 1% of the time.

See my table on http://www.ew.usna.edu/~bruninga/rotator1.html

Also see my real-world model plot of a 3/4 wave monopole over a ground
plane near the bottom of the page:

   http://www.ew.usna.edu/~bruninga/astars.html

It shows that the 19" whip has good gain and lobes for 2 meters but has
almost 8 dB gain on 435 MHz above 30 degrees... and it matches both bands
perfectly to a dual band rig without any fuss.

Bob


----
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org



AMSAT Top AMSAT Home