Simple...
The largest Decibel, Sinclair, Telewave or similar folded dipole
style antenna you can manage to put in the air.
Antennas are probably the only part of the "free lunch rule"...
when applied to radio system coverage.
****
There are two types... the standard folded dipole "Decibel"
antenna like your DB-408, which tends to cover a 10 to 20 MHz
Segment of the entire UHF band. 450-470 is a typical example.
The second type of folded dipole is a much more wide band
antenna sold by Sinclair and a few other companies. You will see
some models of the Sinclair design easily cover 420 to 495 MHz.
The two above folded dipole antennas might look similar but are
fed by different matching systems and their sizes are different.
... and their vert & horz radiation patterns are different.
There is a case to be made for using both the narrow band segment
Decibel Antenna and the wide band Sinclair full band antenna.
cheers,
s.
> "Derek" <[EMAIL PROTECTED]> wrote:
>
> I'm looking for input on what kind of antenna to use for several 440
> MHz amateur repeaters.
>
> Background: Suburban area surrounding metropolitan city of about
> 700,000. HAGL for antennas range from 260' to 320' on 400' and 500'
> towers. I'm looking to maximize mobile and portable input, even
> possibly looking to use 1-5/8" heliax as I recently installed this size
> hardline on my repeater and have been very satisfied with the results.
>
> I've used the DB-408 antenna and am happy with it's performance, but am
> wondering about significant difference in using a DB-420 for future
> repeaters. Also considering the RFS 1151 (Tessco # 435830) fiberglass
> antenna. It is tuned for 440-450 MHz and has 8dB gain, but I've heard
> some say fiberglass is not the way to go for repeaters.
>
> Any thoughts are appreciated.
>
> Derek
>
