[Amps] best tuner

[Colin Lamb]

When the question of "best tuner" was raised, I began thinking about how I would answer.  The more I thought, the less able I am to give a simple answer.  The problem is there are too many variables - literally.  

The problem is that there may not be a best tuner.  I can come up with a load that will cause almost any tuner to fail.  I think the first thing you need to do is to set out all the antennas you may want to load, and on what frequencies.  If you are going to load up an antenna that is close to 50 ohms, life can be easy.  But, suppose you need to load your 80 meter transmitter into a 40 meter dipole?  Or, in one case, during a contest, I loaded up a 80 meter antenna on 160 meters.  

Some antenna tuners do not attenuate harmonics as well as others.  That may not be important if your transmitter is clean.

For portable operation, I use a half wave antenna most of the time, which reduces ground losses.  This requires very high impedances and can be high voltage.  I do not need to operate into low impedances.  

There are a number of computer programs, many based on the Smith Chart, that allow you to pick an antenna, then play with the components to determine how they work - prior to building them.  There are also other qualities an antenna tuner may have.  The L network has a greater bandwidth than others - which means less tuning when you QSY.  

You can build your own variable capacitors, using teflon or glass plates, or build your own inductors.  If you only use one band, you may not even need a variable inductor.

I have about 10 antenna tuners - all different.  Tuners are like amplifiers, you cannot have too many of them.  

73,  Colin  K7FM