FM aerials and riggers
In message , "Dave Plowman (News)"
writes
In article ,
Paul Hopkins wrote:
Last August, Hi-world did a piece on aerials, a copy may be available
from their subscriptions department. They suggested a Antiferance 3
element VHF aerial and an All-rounder dipole ( the round element) it all
depends on transmitters.
Those round things may have made sense if you needed an omni in the days
when VHF transmissions were only horizontally polarized, but these days
all are vertical or mixed for mobile reception, so a vertical dipole is
better.
I use a home-made vertical dipole in the loft with the feeder taking a
few turns around a ferrite ring to act as a balun before feeding
standard 75R co-ax, and it works very well here by the river Trent just
west of Nottingham.
I do get lots of multi-path when an aircraft on its approach into the
East Midlands Airport flies over though!
The home made dipole is based on some cut-to-length copper-plated steel
aerial rods (tapered tubes) from Anchor Surplus (or rather, Anchor
Supplies as it now is), with the central insulating and mounting section
based on glass-fibre extrusions from my local B&Q DIY depot.
--
Chris Morriss
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