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--- blog:2021-03-08:cq_dx_2021 [2021/03/08 14:52] – created ve7tbn
+++ blog:2021-03-08:cq_dx_2021 [2021/03/09 09:01] (current) – ve7tbn
@@ Line 3: / Line 3: @@
 I used this on the recent CQ DX contest as a SOSB on 20 meters. Granted, it was a contest, so LOTS of people were on air but this antenna allowed QSO with Alaska, Hawaii, Japan, Columbia, Brazil, Cayman Islands, Chile, Mexico on an Icom 750 at "100" Watts. QTH was ideal for propagation, ground soil looked good, but regardless, it seems to show that even a simple antenna can work. On a normal day I was getting to various points in the US and once, DX to Rarotonga.
-SWR were mostly ~ 1.5 or lower with occasional spikes, reflected power was low. I operated off a deep cycle battery. A 1:1 choke would be better in lieu of the air wound choke. Choke is about 3' away from feed point. Locating it closer to feed point seemed to hinder performance.
+SWR were mostly ~ 1.5 or lower with occasional spikes, reflected power was low. I operated from a deep cycle battery. Though the coax feed line was less than 30' (including amount on choke), assuming there was some common mode current present, a 1:1 toroid type choke might improve antenna system efficiency more than the air wound choke. Choke is about 3' away from feed point. Locating it closer to feed point seemed to hinder performance.
-Though I used insulated wire, there might be a risk of someone or animal getting RF burn. But radials were slightly above ground, area was at a dead end with lots of brush around, I had a clear view of vertical and radials while operating. Radials being slightly above ground or on ground seemed to make no difference to SWR levels. Ideally, the insulated radial wires would be on the ground (less of a tripping hazard) but, I do wonder if voltage present at radials might ignite wood or other on hot dry days during a long TX at full power.
+Though I used insulated wire, there might be a risk of someone or animal getting RF burn. But, area was at a dead end with lots of brush around and I had a clear view of vertical and radials while operating.  Radials were slightly above ground, at a low angle, but even with wires on the ground, this seemed to make little to no difference to SWR levels and reflected power. Ideally, the insulated radial wires would be on the ground (less of a tripping hazard) but, I do wonder if voltage present at radials might ignite wood or other on hot dry days during a long TX at full power.
 Antenna:
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 - 1/2" (IIRC) grey PVC sections to join bamboo stake poles; at least 1/2 the poles fit; they vary in OD.
-- 16.5' #28 vertical wire direct to coax
+- 16.5' #20 vertical wire direct to coax
 - 4 ground radials direct to coax shield; two radials are ~ 7' others ~ 4'
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 This is a work in progress and not thoroughly field tested. e.g. not tested in high winds!
+edited for clarity.
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