Diamond in the Sky

AW07AI’ve been meaning to write a follow up to my earlier post about the Feature Tech antenna analyser. The short summary of that post was that when I hooked up the antenna analyser to a mobile whip on a magnetic base, I saw all sorts of SWR values which were often not repeatable and changed even as I was taking my hand away from the meter. I was disappointed with the device.

Fast forward a few weeks, in a QSO with Martin VK6ZMS and he was strongly of the opinion that I was doing myself a disservice by running a mag mount without grounding the antenna to my vehicle close to the base of the antenna. Another clue was one idle afternoon at home, I threw the analyser on my WARG Pogo Stick 2m antenna and it had none of the problems I had seen. The SWR readings were reliable (you could read of a value for a frequency, change the frequency then change it back and get the same SWR value) and did not alter as I handled the coax or moved away from the meter. One of the features of this antenna is that it has an coax choke at the base.

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AW07A Antenna Analyser

Kitchen DrawerI like measuring things, this is perhaps best illustrated with this photo of the current contents of the second drawer in my kitchen. Apart from the usual cooking implements, it contains an infra-red thermometer, a compass, luggage scales, gas bottle scales, 10.5 GHz dopper speed gun and a Geiger counter. I also own numerous electronic meters of various kinds. My most esoteric measuring device is probably a Brix sugar refractometer (uses the bending of light to measure the concentration of sugar in a liquid).

So it caused great excitement here when my antenna analyser arrived this week. At over $300 it’s my most expensive piece of equipment in the hobby. I purchased it on ebay, from a seller I’ve dealt with before and it took about exactly a month to get here due to some story about the stock they had being damaged. To their credit, they air freighted it when they finally had stock.

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