Well this is the conclusion after having bit of a play and a fiddle with this 3 element Yagi that I built based on VK5JST build notes. For a 3 element Yagi it is rather directional of about 45 degrees, and very deaf at the back which is a good thing for some setups. Overall it is a rather unusual design with characteristics of much larger Yagi’s for the same band. I have been able to get 1.2/1.3-1 SWR on my Yagi for 146Mhz which I am rather chuffed with and had a good QSO into the VK5RHO repeater from my place. I could probably get better SWR if had a network analyzer to see exactly what the Yagi is doing over 144-148Mhz 2M amateur band.
This Yagi was well worth the time it took to build.
Well today I made the gamma section for my Yagi and mounted it and also added rubber bits for the ends of the elements and end caps for the boom. I have done a quick test of the Yagi with a 10pF capacitor and the SWR is ~1.5-1. I got a couple air variable capacitors I going to put on the Yagi to better tune it. As it was a lovely day most my work was done outside on the deck.
Tonight this is the bracket I made for the SO238 socket all riveted and mounted to the boom of the Yagi. All that is left to do is make the bracket to hold the gamma matching and to fine tune the Yagi, all going well I should have it finished during the week
and yes working on the kitchen table again, hehe
This is a 3 element 2 meter band Yagi design by VK5JST that I am giving ago to make. The only difference is I am using 12mm OD round and 19mm OD square aluminum (as it what had around from another project) and I have used 3.2mm dia x 4.5mm long aluminum rivets to hold the elements to the the boom. All I have left to make is the bracket to hold the gamma rod and the bracket for the connector and drilling the holes for the v/u bolt assembly.
The pictures below are where have got thus far.
and yes that is the kitchen table I am working on, ssh don’t tell anyone. hehe