So gently getting back to the topic of the original post which was:
Getting thoughts on relatively simple and relatively inexpensive
portable 160 m antenna, potentially deployable by one person, that
allows for flexibility and somewhat predictable tuning for use on modest
Dxpeds or rare location indigenous ops.
Strawman proposal was for Inv L 50’(or more) alum mast with elevated
radials all tuned with “hairpin” shunt coil – plus a request for
suggestions and potential actual physical assistance with
testing/assembly/distribution.
Principal thoughts to date by TB types posted and direct:
1. More top wires than just one
– doable with minimum additions provided the site has space. Should
improve performance somewhat, requires top wire supports in other
directions (which may only be a minor issue) and some more wire.
2. Mast higher than 50’
- I believe at 55’ (~17 m) it is still quite possible to hoist it up
(maybe not walk up but a rope attached 1/3+ of the way up)
3. Use 18 m fiberglass telescope instead of alum.
- Doable and can be walked up they say, but nearly twice as heavy as
alum, more expensive and bending at top reduces effective height a bit.
But still if you’ve got one . . .
4. Ground radials instead of elevated.
- Could be good for some locations but requires 20+ m radius circle
thick with wires. The innkeeper might not be pleased and also space may
not be available unless you go the tent/generator route. I suppose the
antenna product could be in two flavors, ground and elevated, with
possible different tuning of the top wire.
5. Go to a site that has nicely spaced high palm trees (on the good
propagation side of course) and then . . .
- I welcome volunteer advanced palm tree scouts. Yet perhaps not all (or
even most) interesting 160 m entities have palm trees.
- Yet the point is well taken that a good site with advanced planning
(Google Earth/eyeballs) is important (when possible). This matter has
been looked at for KH8 but I am looking at broader uses as well.
6. Matching not worth the effort with modern ATUs
- Yes but I would not think of trying a semi-serious 160 m effort with
low power (or difficult to match antenna), and the high power matching
units have $, size and weight issues. The current plan has the charm of
a simple, flexible matching coil even at the expense of tuning by
fiddling with top wire and/or elevated radial lengths
7. Receive antenna use
- I purposely did not mention this just to see if it would be seen as an
oversight among TBers. My only personal experience is I don’t have one
and there have been a significant number of high end 160 stations (who
surely have Rx ants) I could hear but could not hear me (my ant is a bit
better than the one proposed here and with 500 w). Of course, his story
may not hold up for a rare-ish DX station.
Anything else?
Bill N6MW
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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