Crusader Beam, the beginning:

One of the locals here CDX 144 (Steve) installed one of my Interceptor 10K 5/8 Ground Plane Antennas. He had it on top of a 60 Foot tower, using the LMR-400 Coax, the good stuff.

He was happy with the Interceptors performance, but wanted a beam to reject undesired skip stations. Steve put up a 4 element beam after cleaning and tuning it.

Getting the beam up was not hard with Steve as his 60 Foot Tower is a crank up and tilt over that he designed and built. Steve is a machinist so this all came real easy for him.

Steve noticed with the beam up that it was just as strong as the I-10K 5/8 Ground Plane Antenna, making field strength tests with the locals. He asked me over to look at the beam, asking what's wrong, because it wasn't any stronger than the I-10K Antenna. I looked the beam over thinking that the element lengths or spacing was all wrong but Steve had done his homework and he got it all correct. Using the same LMR400 Coax and the tower, how could he go wrong? I asked him if he somehow get the wrong field strength readings. He said that he even put the I-10K back up and tried it again, with same field strength results

I came to the conclusion that the only thing I could think to try was to remove the old original Gamma Matching Rod and Driven Element, and install a hairpin / beta Matching System like what I use on the I-10K Antennas. I gave Steve some old left over parts from a old prototype Interceptor 10K with a diagram on a lunch sack. (real professional!) Steve put it all together and had it tuned in no time. The photos here are of the highly modified Yagi Beam Antenna, with the original factory Gamma Matching Rod and single piece driven element, replaced with a Hair Pin / Beta Matching System and a split insulated driven element, with a Coax wound Balun.
Now with the Modified Yagi Beam Antenna, the field strength measurements showed approximately 6 dB stronger as compared to the I-10K 5/8 Ground Plane Antenna, just like a beam should be.
I have other antenna people testing a "Bolt on" after market Beta Matching Network, and split insulated driven element, and comparing it to the stock original Gamma Matching Rod and single piece Driven Elements. It will be interesting to see if the Beta Matching System is more efficient than the Gamma Matching System, ...... More to come


After significant testing, we've found that the coax balun just doesn't work well on the yagi antennas. As a result, we are now using a torroid balun and the results have been tremendous. To the right is a Crusader 10K with a new torroid balun mounted by the hairpin / beta matching system.

Below is a scale model of the Crusader 10K with a 25 KW balun attached


The Crusader 10K 5 element Yagi is still under construction and testing, in the manufacturer's antenna test range facility (the big back yard). More to come on the Crusader Beams......