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--- hw-20hp [2026/01/21 14:54] – admin
+++ hw-20hp [2026/03/08 16:35] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
 The claimed 5 band performance is obtained:
-* with a slight slope, 6m one end & 4m the other, longer 2/3 section highest;
+  * with a slight slope, 6m one end & 4m the other, longer 2/3 section highest;
-* with about 20ft feed line
+  * with about 20ft feed line.
 <del>Do not put a choke or common mode rejecting 1:1 unun (balun?) at the feed point. I got **very** high swr on all but 20m and 10m with a choke there.
 However: I have yet to try with a broadband choke (I used an air-core 'ugly' balun).</del>
+So I foolishly succumbed to the lure of an air-core 'ugly' balun and wound one close to the feedpoint. This ruined the whole thing. Just don't do it. Two theories: it's too narrow band which is true but where is the band? the antenna needs some feed line as an impedance match to 'soften' the resonant peaks. This works like a resistive divider and implies some loss in the feed coax, but saves having to use an antenna tuner and is no less efficient.
+So to remove the rf buzz I get on the shack power lines, I added a proper broadband rf choke, but it mucks up 17m - goes from 1:1 to 1:2.1. It also reduces receive sensitivity by (just measuring by eye) 1s too. I guess I'll leave it off.