Category Archives: antennas

A center-loaded squid pole vertical for 7MHz

A 40 meter dipole in the conventional or inverted-vee configuration is a fine antenna for portable operation, providing reliable communication around the southern states during the daytime . My first few SOTA activations used a 40 meter dipole slung from branches at 5 or 6 meters.  It worked perfectly.  Next I purchased a 9 meter squid pole from which the dipole was hung, albeit from the second or third telescopic segment down from the tip for rigidity.  This eliminated the need for a convenient branch and the lead weight swinging, and the ever-present risk of missed shots getting tangled in out-of-reach branches.  But at times the task of walking out from the activation point and tying off the two 10 meter wire elements to suitable tree branches felt a bit tiresome, and on some summits impractical.  The popular end fed dipoles preferred by many current activators span a similar lineal distance, although they allow the radio to be positioned close to the feed point and dispense with the 10 meter length of coax required to feed the center-supported dipole.

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The parts that make up the center-loaded vertical — the blue fishing spool holds the driven element wire and its loading coil. The red spool holds the 4 radials with banana plugs. The termination box and 3 meters of coax provide the feed.

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