> I have a Phelps-Dodge VHF antenna about 21'10" long.
>
> Tell me about the three radials at the bottom.
> For the 2 meter band, what should the length be?
>
> The NCG GP-6 antennas use about 19.5" long radials.
>
> Should the radials be straight, like the GP-6, or angled down
> some degree(s)?
>
> What should the length of the radials be, for a UHF band antenna?
It depends on which model antenna you have. From what I've seen, having
disassembled many, those that are comprised of coaxial half-wave elements
(VHF PD220, UHF PD1151, PD455, etc.) use radials sloping down at a 45 degree
angle for decoupling only. The length of radials is nominally 1/4 wave, but
they are slightly shorter than that physically due to their width. For
antennas that are non-coaxial elements, the radials are at a 90 degree angle
and serve more as a ground plane. PD200 on VHF, PD400 on UHF have 90 degree
radials. For these antennas, the radials are arguably more critical than
the models where they are used for decoupling only.
If your VHF antenna is in the 21' range, it could be either a PD220 or
PD200. Does it still have a sticker on it?
--- Jeff
--------------------------------------------
Jeff DePolo WN3A - [EMAIL PROTECTED]
Broadcast and Communications Consultant
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