I recently did almost this same project in Tortola, BVI (VP2V) 4 weeks ago.
I have been helping as a consultant to ZBVI for the past 20 years.
I was part of the team that installed a new 300 ft tower for ZBVI when the
old tower came down due to an accident with a guy wire.
The station goes off the air at 10 PM so I was able to use it for a few
hours on 160 during the CQWW 160 CW contest in late January.
I designed the tower feed system as a slant wire (shunt feed) for AM
broadcast service so that no base insulator is needed (helps with horrible
lightning issues). Then I used a T network to match the slant wire to insure
the proper bandwidth of the match and for long term stability.
I can bypass the T network and then with a simple L network I was able to
match the tower (slant wire) perfectly for 160 meters.
The TX was great - RX not so much (very high noise level).
73,
Tim
VP2V/K3LR
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of DALE LONG
Sent: Tuesday, February 25, 2014 3:18 PM
To: topband@contesting.com
Subject: Topband: AM broadcast tower and 160m dxpedition
Gentlemen:
I have been reluctant to ask for help which did not relate directly to our
reflector. But today I got up my courage, so here goes. I have been invited
to lead a group of amateurs to help build an AM tower in Haiti.
Two things that may relate to some of our readers:
1. I will be returning to Haiti in November to build a 240foot AM broadcast
tower. I know there are many AM broadcast engineers on this list and would
like to have your advice. Specifically we are searching for a large conical
base insulator. Sometimes when a tower rusts, they are disgarded or thrown
on a pile somewhere. We would like to buy one, and possibly a tower as
well.
2. In December of this year, I am organizing a small group to go to Haiti
and participate in the 160m contest. (this of course is dependent on the
tower being built.)
I am particularly pleased that amateurs have been invited to help. Sometimes
broadcast engineers do not have the highest opinions of amateur
installations. So we do want to do it right. We have a 9-acre parcel of
land along the ocean and part of the area is a salt-water marsh. I think
there hasnt been any serious 160m activity from Haiti for a number of years.
This location would present a nice opportunity for a serious lowband
operation.
If you have any information about base insulators/towers, or if you would
like to join a 160m dxpedition to Haiti, please respond off the reflector to
n3bna1@gmail.com
Thanks for your time.
Dale - N3BNA
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