[Kenwood] Tuner vs. Antenna

[Scott Manthe]

To use the internal tuner, you'll have to keep things close to 50 ohms- 
probably between 15 to 150 ohms, maybe a little more. I'm not sure that 
the internal tuner will like anything more than about a 3 to 1 mismatch.

It sounds like you've been listening to some confused people. A balun 
simply matches an unbalanced feedline, like coaxial cable, to a balnaced 
feedline, like ladder line or twin lead, or antenna. Which balun one 
uses is entirely dependent on what type of antenna or feedline is being 
used. Some are suitable for some types of antennas, some aren't.

One would not run ladder line to a 1:1 balun. 1:1 baluns are used on 
resonant dipoles,where the feed point impedance is about 72 ohms.

Multiband wire antennas, like G5RVs and Carolina windoms, as well as 
many others don't have a fixed feedpoint impedance, since they work on 
many bands. Because of this, designers often use 4:1 or 6:1 baluns to 
match the often very high feedpoint impedance to to get closer to the 50 
ohms coax the antennas are generally fed with these days.

Given this, I'm curious about which design requires two baluns? If you 
used ladder line from the feed point, you should only need 6:1 or 10:1 
balun at the transition from ladder line to coax and it wouldn't make 
sense to have one at the feedpoint as well, unless the antenna was 
designed by a balun manufacturer.

Check out this windom design: http://www.kh2d.net/windom.cfm

I know KH2D and he doesn't exaggerate his antenna performance.

73,
Scott, N9AA

ken robinson wrote:
> Interested in comments on types of antennas being used for 80-10 meter on
> the 450SAT, and similar rigs, and how effective the internal tuner is in
> matching the rig/antenna.
> Some people suggest a 1:1 BALUN on a dipole and then ladder line. Others
> call for a 4 or 6:1 and then coax or ladder line, and then a tuner.
> I am considering a Windom with ladder line. The design I am looking at uses
> a 4:1 balun at the feedpoint with a 1:1 at the transition to coax.
>
> 73 de KI4VSQ
>
>