MGFoster wrote:
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Michael Coslo wrote:

What is the antenna length?


Now as for Al foil as an antenna construction material:

It works electrically, but isn't very strong. Your cardboard tubes
aren't terribly weatherproof either. You might be able to shellac them

heavily. But still it isn't a very good choice.

Making contact with the aluminum could be an issue. Tubular aluminum
is
used on antennas, but the connection is usually helped by corrosion
inhibitors, and nuts/bolts with washers to help "dig in" to the AL.
Your
thin foil will deform at best, and more likely rip with that sort of
treatment.

The antenna is abt 34 ft (1/4 wave for 40 meters).

Okay. Assuming that is 34 feet per leg, you might be cut a little long
for 40 meters. (Let me make sure I'm correct here - this is a linear
loaded dipole, yes?)

What would be good to know is the frequency where you are at your lowest
SWR.

Can you beg borrow or steal an antenna analyzer? Your antenna is
probably cut for somewhere outside of where you can transmit with your
rig. That would be the quick way to find out. Otherwise you should take
SWR measurements across the band to see if that gives you an idea about
how the antenna is cut.

Another thing is to try a measurement without the capacity hat - see
where that puts you. It might just get you a lot closer to tuned.


The cardboard tubing was for weight - this ant. was to be a portable
ant. and would be deployed only in good wx.

"Treatment" - that's why I wrapped the tubes/foil in clear plastic
wrapping tape. Barring me accidentally smashing them or some
discombobulated squirrel "having at 'em" I'd expect them to last for abt
a year or 2.


Well, you can give it a try, homebrewing is a big part of the fun in
Ham radio.

- 73 de Mike N3LI -