From: david park <dpark748@hotmail.co.uk>
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
Dave,
All your answers so far are on the money - shorten > increase freq;,
lengthen > decrease freq.
When you complete the suggested graph, my bet is the freq with lowest SWR is
too high. That ain't all bad, as they say, because if the antenna is
embedded, to shorten it would mean digging out. However if the antenna is a
smidgen short a judicial drill into each end of the dipole will permit an
electrical screw to join the original embedded to external extended strips
which may be newly trimmed onto freq.
Good luck Ferg
PS: ...or you can contact the nearest Ham club - a lot of what they do these
days is design and refine their antennas
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