15 Meter Yagi: Gamma or T Match?

[w8khk]

Yesterday the weather was fair long enough to adjust the driven element and gamma match.  Tower base is grounded to 8 separate ground rods.  The ugly balun is wound with no form, but wire ties keep the coil in a solenoid, or cylindrical shape.  Ready to raise the Yagi!

[w8khk]

With the gracious assistance of my good friend Rick, W4BYT, we raised the antenna today.  Full size 3 element 15 meter Yagi, and a 2M / 70CM vertical at the top of the mast.

Next it is necessary to feed the cables to the shack, then it will be alive.

[w8khk]

I followed the suggested method of tuning the driven element length and gamma match L and C by pointing the yagi skyward, with the reflector on the ground.  I was suspicious that this might not provide a decent match when the antenna was at the top of the tower.

To my surprise, the radiation resistance and reactance at the end of the 50 foot RG-8 cable were totally acceptable for operation in the phone portion of the 15 meter band, and definitely useful even down in the CW end if I decide to go digital.  

The only remaining question is whether the dielectric in the gamma capacitor will behave with QRO.  If not, it is relatively easy to fold the tower over and replace the matching section.  I used a teflon sleeve between the inner and outer gamma tubes.

MFJ-259 stats attached.  Gain and F-B ratio will be more difficult to measure, but I am sure it will beat the 126 foot dipole for DX on 21 MHz!