My Inv L is for 160 mters is 128 feet long. It is a true 1/4 wave. The nice
thing about using a pure 1/4 Inv L, is that you can use a Amidon Unbalnance
to Unbalanced transformer (UNUN) to match the impedence of the coax (50 ohms)
to what ever the impedence of the Inv L will be (it will seem to range from
50 ohms with no radials down to 17 or so ohms with lots of radials for 160
meters) as you add radials, you will see the SWR go up, as does the ratio of
the impedence mismatch- but don't sweat it- your only improving the ground
system and the SWR should still dip at your most resonant point- even if it
is 7:1................when you match the feedlines, using the UNUN, you will
have a great match! My Inv L only goes straight up 55 feet- the rest is
pulled away from the tower about 160 feet leaning towards EU- I use a single
4 foot stand off on the tower and a pully put onto a 2x2 8 foot piece of
redwood to hang the antenna about four feet of the side of the tower- - easy
stuff but can take awhile to figure out- I have 90 1/4 radials, all laying
on the ground secured by landscaping spikes- 73 Paul N0AH
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