HY-GAIN TH3-MK3 Thunderbird Antenna - for 10, 15 and 20 meter

Manual in PDF

RENOVATING the antenna in 2013 - resonance gone so I had to...

Trimming the antenna to the best...

My new VNWA from SDR-Kit.
New measuring and optimizing the antenna for best performing:

Summer 2011 - Optimizing the antenna

Now the resonance is about what I want, when running CW.

My EXPERT 1k-fa is able to use all the 20 and 15 meter, and on 10 meter I cane use from 28 - 29.250 MHz without any problems

I found a fundamental error in connection the BALUN/Cable and the antenna. After this error all I now working with better SWR than earlier.

20 meter band
After re-calibrating the VNWA with more horizontal points, it is possible to get a more accurate measuring. 

Between MARKER 1 and 2 the EXPERT works very perfect.

Best resonance at 14.123 MHz

15 meter band
10 meter band


First Measuring Autumn 2010 - just for the record...

This picture shows RETURNLOSS and VSWR for TR3 on all 3 bands on my new VNWA.

The cable is Calibrated out, so the measuring-point is on the antenna-connection.

The DATA of the antenna is used precisely, and exactly as shown.

The antenna is mounted 11,55 meter over ground.

The PA, EXPERT 1K-FA have BUILD-IN tuner, and the antenna is usable at following frequencies:

20 m: 14.000 MHz - 14.350 MHz

15 m: 21.000 MHz - 21.500 MHz

10 m: 28.000 MHz - 29.000 MHz

The 10 M-band could bee expanded a little by mowing the frequency up a little, but as CW enthusiast I wish to have a good VSWR in the low end of bands.