Sunday, July 11, 2010

KH6JRM's Amateru Radio Blog

The Homebrew vertical "antenna farm" is doing well at the
Laupahoehoe QTH.  The most recent project is a nearly
out of sight vertical helix that works well on 40 and 15
meters.  I had a 10' piece of schedule 40 PVC pipe under
the house which I pressed into service this week for an
easy-up antenna.  I wound 66' of number 22-gauge hook-
up wire around the mast in a helix configuation and topped
it off with an 18" stinger for some top loading.  A 3' to 6'
capacity hat would probably be more helpful in raising
antenna efficiency, but I opted in favor of the single wire
on top.  I strung out eight 10' foot radials and attached the
creation to some RG-6 I had on hand.  I fed this into the
Drake MN-4 ATU.  The Drake handled the mismatch and
the Swan 100 MX seemed happy with the arrangement.  The
bandwidth is quite narrow, but retuning is no problem.  This
antenna might be of interest to those of you bothered by nosey
neighbors or for those needing a quick emergency antenna.  I've
run a few of these fed by 300 ohm and 450 ohm twin lead.  They
all work.  As you would suspect, this type of antenna won't work
as well as a full quarter wave stick with a good radial system, but
it does work if  you need something in a hurry.  Good luck in  your
antenna projects   Living on a small lot makes for some interesting
antenna experiments.  I just use what I have available--such projects
appeal to my parsimoniouse character.  Alright, I'm just cheap.
Have fun designing your own antenna farm.  Aloha, 73 de KH6JRM.