5/22/09

"Getting the Most Out Of Your T-Network Antenna Tuner", by Andrew Griffith, W4ULD, QST, Jan 1995.

My comment is that considering the first tip, I would start step 1 with the lowest inductance, which should relate to highest C-out.  Then, do steps 2 thru 5, trying higher inductances as needed.
 
It really made my Ham experience nicer when I "mastered" the art of antenna tuning.  Now, I can work on just about any frequency using my 80 meter vertical (with raised radicals). 

Excerpt from "Getting the Most Out Of Your T-Network Antenna Tuner", by Andrew Griffith, W4ULD, QST, Jan 1995.

Practical T-Network Tips
To achieve the highest possible efficiency...tune the network with the highest output capacitance that allows a match...more C-out translates to less loss.
For Tapped-Inductor Tuners
1.  Set C-in and C-out to midscale. Select an inductance switch position, and rotate C-out through its range to look for an SWR dip.  The dip may be very sleight.
2.  If you don't find a dip, set the inductance switch to another position and adjust C-out for an SWR dip.
3.  When you find a dip, adjust C-in for minimum SWR. 
4.  Inch C-out in one direction or the other, and redip with C-in.
5.  If the SWR is lower now than it was with the previous C-out setting, continue to inch C-out in the same direction and redip the SWR with C-in until you obtain a 1:1 SWR.
In some cases, an SWR dip can be obtained with two inductance settings.  Choose the setting with the lower inductance to get the larger output capacitance.