"WonYong,Lee" wrote in message
...
I made a pixie2, QRP rig.

and so, I need a simple antenna...7Mhz!

and double loop coax antenna is attractive very much...

http://www.greertech.com/hfloop/mymagloop.html


but...Antenna tuner is nessasry??

I can't make a tuner because, air variable capacitor is few in
korea....

only loop antenna works well??




Hi OM
Many antenna designs work well.
What they often have in common (besides location) are resonance and matched
impedances.
You can make a resonant antenna in many forms. It's impedance will vary but
will always be resistive by definition.
Impedance matching transformers work. I like toroids; Low radiation, wide
bandwidth.

Reactive components are not necessary and contribute to losses anyway;
I learned that fact the hard way while sorting out the last of the bazookas
on this very newsgroup.

Do you have 66 feet? Then a simple dipole is the best choice. If you've only
~50 feet, droop the ends.
Feed it with 50 ohm coax, spin 8-10 turns about your hand and tie it
together at the feedpoint.
(Choke balun.)
Be preared to walk back-and-forth as long as it takes to trim the lengths
correctly.
Resonance is everything.
73
H.
NQ5H