DSE Antenna Tuning and Rig Expert AA-600 Analyzer

As you can tell from this blog, I’ve been taking some big steps to elevate (so to speak) my VHF-UHF rover operations. Part of that is due to the demise of my push-up mast at home along with the limited space to put up anything else. The other part is that I really like VHF-UHF contesting as a rover.

Directive Systems Rover Yagis

You may have read about my new VHF Contest Rover Setup. That involves a rotator, mini-tower frame, thrust bearing, and on top of it all Directive Systems 144 and 432 Rover Yagis, both with eight-foot booms along with a Par Electronics Stressed Moxon for 50 MHz.

Rig Expert AA-600 Analyzer

The only antenna analyzer I’ve used in the past was an Autek RF-1 that covers up to 30 MHz. Based on Terry Price’s advice from Directive Systems, I purchased the Rig Expert AA-600. Well actually he’d advised the AA-1400, which has the advantage of covering 900 and 1296 MHz. However, the price is nearly twice as much. So I opted for coverage up to 600 MHz that directly addressed my requirements for limited rover — the first four VHF-UHF bands.

Tuning the Yagis

I had originally tuned the yagis while mounted in the rover set up. But, of course, there’s a great deal of interaction happening. So I felt it might be wise to tune them according to the DSE directions…

They suggest mounting them pointed up with the feedpoint at about shoulder height. You can see my set up nearby using a portable work table, an eight-foot board, and some bungee cords. I’m sure that has its own set of interactions, but it’s what I have.

The 432 yagi has a relatively broad resonance. So I was able to tweak it a bit to obtain a low SWR. The 144 yagi seemed to struggle getting the resonant point on 144.2 MHz. But I was able to get it tuned to the lowest SWR at 144.2. The measurements for the match came very near the recommendations in the DSE documentation.

I also used Rig Expert’s Antenna Scope software on my Windows Laptop. That helped me see things a bit better and to print out the graphs for my records. You can see the graphs nearby.

All in all, I’m pleased with the rover yagis and the AA-600 antenna analyzer. Next is proving they work in the ARRL January VHF contest. Hope to work you from several grids.