Jim=2C
Thanks for that=2C yes I did use the coax that came with the kit - major jo
b to change that now - unless it is worth making a connection in the tail a
rea to the kit coax with RG58??
I am just a bit concerned that if I keep cutting to achieve 1=2C5 at 127.5
=2C presently 133.0 I might bxxxxx it up compleyely!
Dave
Date: Fri=2C 26 Mar 2010 21:59:15 +0000
From: jimpuglise@comcast.net
Subject: Re: Europa-List: Antenna tuning
David-
I assume you are talking about the copper strip antenna that comes with the
kit. My own approach is to start at the bottom of the band and record the
SWR every 50 khz. After you have done this=2C put the figures in Excel an
d graph it. Each line in your Excel spreadsheet shoud have one frequency i
n column A and the SWR at that frequency in column B. In this way=2C you c
an see what the antenna is doing through the entire band. You need to be c
oncerned that the SWR is not extremely high at one end and extremely low at
the other. I usually shoot for 1.0-1.2 / 1 at the center and 1.9 or so at
each band edge. If you are at 1.5 in the middle of the band=2C that shoul
d be just fine. The reason you are not seeing change with small adjustment
s is that it is probably relatively flat a few MHZ each side of resonance.
Also=2C I don't know if you are using the coax that comes with the kit=2C
but I took one look at it and threw it away. Invest in some good RG-58 for
the comm antenna and some RG-400 for the transponder. When you look at th
e graph=2C it will be very obvious what you need to do.
Jim Puglise A-283
----- Original Message -----
From: "david park" <dpark748@hotmail.co.uk>
Sent: Friday=2C March 26=2C 2010 5:43:11 PM GMT -05:00 US/Canada Eastern
Subject: Europa-List: Antenna tuning
I have just borrowed an SWR meter and am trying to tune my Comm antenna. T
he manual says to tune by shortening until minimum reading at 127.50 I am
getting Minimum reading at 133.00. My last two cuts of 3mm have not moved t
he minimum reading 1.5 at 133.00 above and below this frequency the reading
s are at 1.9 -1.9.
Do I keep shortening the antenna????
Any ideas? Regards Dave Park G-LDVO
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