RadioBanter - View Single Post - Supposed comparison of Mobile HF Antennas in November QST

Michael Coslo · October 29th 07, 05:51 PM posted to rec.radio.amateur.antenna

wrote:
On Oct 26, 1:20 pm, Michael Coslo wrote:

I've considered putting a tuner on my Bugcatcher for 80 meters, but
haven't. The thing is so narrow there that the alternative is two taps
for the phone portion of the band.

That would more more for impedance matching rather than the
loading coil itself. I have no real problem with that. I've often used
simple L network tuners for matching mobile antennas.
The system I have a problem with is using the tuner as the
loading coil itself. It's usually a disaster as far as efficiency.

Okay, I got it, it makes sense that "tuning the coathanger" approach
would be bad.

Maximum current is at the coil, and often that coil will be
surrounded by body metal. Not good.. Poor current distribution
through the whip, and low overall efficiency. Not good..
If they left out bugcatchers in the test, no wonder all those
tuner fed things looked so good...
If your antenna acts very "high Q", that's actually good.
It means it's probably a pretty decent radiator.
I'd be more worried if it acted overly broadbanded, or low Q.
You won't lose much if you use a tuner for Z matching in your
case.

I've been pleased so far. I worked some CA QSO party from the middle of
PA on 20 meters with it, and all I could hear I could work (100 watts)
Florida, the midwest, and all the typical 20 meter paths from here too.

40 meters received good signal reports. I worked South Carolina, the
Outer Banks, Virginia. Maine Not enough to make a definitive statement,
but it doesn't not work. No QSO's on 80 yet, but the next evening I take
it out, I'm giving it a try.

It is narrow, but that's only been a big problem on 80.