2 Meter Quad Antenna Design4/22/2021
The local variety is to have one person transmit from public access property, fixed location, once every few minutes.All the hunters start from the same location and attempt to triangulate the foxs location based on readings of their signal with directional antennas.I used the original version of this antenna I built for quite some time, and then rebuilt it a bit sturdier, which unfortunately made its weight and wind load too high for my comfort for ARDF use.I am planning on building another using PVC or any other light weight materials I can dream up.
As I can find no other record of it anywhere but on web.archive.org, I am republishing it below in its entireity. During this discussion the comment was made, quads dont work on VHF This comment spurred an overnight design and assembly project that resulted in this 4 element optimum spaced quad beam. This same antenna design won the antenna gain measurement contest in the category of highest gain for the shortest boom length. It came in with a signal gain of 10.1 dBd. The next highest gain antenna was an Oliver Swan (later to become KLM) bandpass log periodic type yagi of 13 dBs with a boom better than twice as long. The first antenna of this type was fabricated of wooden furring strips, and 12 gauge copper wire. ![]() The antenna will provide a fine signal for any two meter home station, and has also worked well in the past for mobile or portable applications, as well as transmitter hunts. The antenna will match 50 Ohm transmission line directly with no other device needed. An RF Choke of several turns of coaxial cable is recommended for symmetric antenna aiming. Let me emphasize again that all structural portions of the antenna must be fabricated from non-conductive materials. It is recommended to build the first such antenna you attempt from wood. Fabricating all pieces can be done with simple hand tools, and the element spreaders can be cross notched and secured to the boom with 14 X 3 inch bolts, nuts, and lock washers. A 1 12 inch TV antenna type U-bolt is used to mount the boom to the supporting vertical mast. ![]() ![]() Hold this choke balun in place with electricians tape and or plastic tie-wraps. If the smaller RG-58 is utilized, total coax length should not exceed 25 feet. Longer runs of this relatively lossy cable, will throw away signal gain wastefully on both receive and transmit This smaller cable will also compromise the antennas power handling capability. Using RG-213 the antenna can handle several hundred watts of power.
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