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Hi G,
Well the Laws of Physics dont change however much
one might wish it :-))
The unipole will be approx -3dB ERP on the inv
L
Effective height of unipole approx half physical
height
Effective height of inv L same height with 1.5*h
top is approx 0.9* physical height
inv L disadvantage.....requires another support and
insulators
inv L advantage ........over poor ground with the
same feed-point grounding the inL will have lower ground loss and higher
capacity. Over good ground or sea-water this advantage may disappear, but losses
will be low anyway.
I think this folded monopole is covered in Rik's
tutorial, the extra wires are just "matching" they dont increase the radiation
resistance. Commercial stations like grounded aerials for lightning
protection.
Alan
G3NYK
----- Original Message -----
Sent: Friday, May 08, 2015 4:54 PM
Subject: LF: UNIPOLE V INV-L ?
UNI-POLE V INV-L ?
Assuming a robust ATU and earth
What would be the advantage / disadvantage
of say a 40 foot uni-pole
, to a conventional 40 x
60 ft inv L at MF ?
tower and side wire or RG8U /
copper pipe construction ? ......... -3 dB of a
similar size loop ?
73-Graham
G0NBD
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