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Frequency - 135-160
Gain - 3dB (manufacturer's claim)
Power Handling - 1000 watts
Price - +/- $50
Cushcraft Online Catalog
So I've been a ham for a few weeks and I received this antenna used as it was going to be thrown away. Actually it lived in my garage for the better part of a year until I finally had the opportunity to use it.
It seems to be solid and well built, almost 100% aluminum with some plastic and stainless steel hardware. It stands about 40" tall from tip to the bottom of the base. It has IMO, some minor flaws that I will discuss later.
To tune the antenna I mounted the antenna on an aluminum pipe about 6 feet in height and used the MFJ-269 Antenna Analyzer. http://www.mfjenterprises.com/products. ... id=MFJ-269 Tuning was pretty easy using the analyzer though you have to not only slide the top section of the element up and down, but also tune the ring, which is a matching network of sorts, at the base of the antenna.
After about 30 minutes I had the antenna tuned exactly where I wanted it, with the resonant frequency at 146.000 Mhz. I achieved 1.1:1 match throughout the entire 2 meter band with the exception of 300KHz at the band edges where I still had an SWR of 1.2:1. Tuned to resonance at 146.000 MHz, the antenna will operate with an SWR of less that 2.1:1 from 137 - 151 MHz.
I read some reviews where people were having trouble with stray RF coming back down the outside of the feedline with this antenna so I figured I would think ahead a little. I made about 8-9 turns of coax around the mast directly below the feedpoint in order to create a choke balun to de-couple the antenna from the coax. I have zero problems with RFI or any stray RF after doing this. I will say I have not transmitted without the choke so I can't really say if it helped or not, but like I said, no problems.
The antenna actually fits down over top of the mast and utilizes a stainless steel set screw to tighten against the mast. The threaded "nut" inside the antenna's base had seperated from the antenna and just spun when I tried to tighten it down so I removed it and drilled a few holes the whole way through the antenna and through the mast. I fastened it with some 1/4" 20 stainless steel bolts, washers, and locknuts and it works just fine. I suppose you could U-bolt the base of the antenna to the mast as well, but I am not sure how this will effect the performance of the antenna.
The coaxial connection is an exposed UHF female connector (SO-239) bolted to the slide on the matching ring. This is kind of poor because it does allow you to really seal the weather out neatly. To remedy this I made a 12" long pigtail with a UHF male (PL-259) on one end and a mini-UHF female connector on the other. I attached the male end to the antenna a slid some heat shrink tubing over the connector to seal out the weather. To the other end I attached the rest of my feedline (equipped with a mini-UHF male connector) and heat shrinked that connection as well. We've had some rain here since and everything seems to be high and dry.
I was pleasantly surprised with the AR-2's performance. The receive is very quiet. On FM I can work simplex stations 30+ miles away with an S-9 signal on my Icom IC706MKIIG. I have also manage to get into several repeaters up to 75 miles away on 50 watts! Although my QTH is 830' ASL, one must keep in mind that the tip of the antenna is a mere 25' off the ground. Not too shabby!
The gain claim of 3dB seems just a bit high. Since this antenna is not much more than a 1/2 wave end-fed dipole I can't see it having much more than 2dBI gain. Marketing perhaps, but who knows I am far from an expert in that area.
Solid construction using stainless steel hardware and heavy weight aluminum.
Great match across entire 2 meter band.
Small, low profile, non-obtrusive footprint.
Will handle high power.
Poor antenna connection design.
Crappy set-screw mast mount.
May be difficult to tune for optimum performance with just a wattmeter.
Overall I am impressed with the performance of the antenna considering how low the antenna is mounted and how inexpensive it is. Are you gonna win contests with it? No way, but for local and reasonably distant FM work and local SSB ragchewing it's a pretty darn good antenna for the money. Definately a good starter base station antenna.
I give it....
wraping the coax also will provide a very small amout of lightning protection. as the lightnig does not like to make turns in coax . it should blow out the side and ground to the mast pipe. DO NOT TREAT THIS AS GOSPEL. DO YOUR HOMEWORK.
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