Topband: Interesting New DX Engineering Product

[Jim Brown]

One of the guys in our local ham club came back from Dayton with a 
very interesting new product from DX Engineering. As soon as he 
showed it to me, I called up DX Engineering and bought two of them. 

The product is a unun autotransformer for HF antennas designed to 
transform 12.5 ohm or 25 ohm loads to 50 ohms.  This is a natural for 
matching any resonant short antenna to a modern transceiver. You 
must, of course, do something about the reactive component.  Opening 
up the box I see good components that will handle some power and 
solid, but simple construction. The website data sheet suggests that the 
unit should handle 500 watts with a reasonable VSWR. 

There are also several variations of hardware to add a capacity hat to a 
vertical antennal.  While mobile antennas are an obvious application for 
both of these products, both could also find good use in a home 
antenna farm. Used in combination, I can smell more than a few dB of 
improved efficiency. I think I also smell Tom Rauch's hand in the design. 
It that's true, many thanks, Tom!

Jim Brown  K9YC