I finally gave up on trying to find a place to put a dedicated JA Beverage on my new property and decided to make the existing "East Coast" Beverage reversible. Instead of using a two wire design, I went with one wire and feedlines to each end of the Beverage. The long one is about 1/4 of a mile long - but am using 1/2" hardline, so the loss isn't prohibitive (less than 2 db).
I used a homemade TDR to look at the antenna and can see the impedance discontinuity at the "end" - which is back in the shack. I can see some "roughness" corresponding to the Beverage wire and some small blips at the impedance transformers. I made the transformers out of BN-73-202 cores, with two turns on the low impedance side and 5 on the high impedance. This is the first time I have used these cores and they work really nicely up to 30 MHz no problem. With the far end open, I see a positive pulse on the TDR as expected, and a negative one with the far end shorted. Putting a 68 Ohm resistor (the closest I could find to 75 Ohms in my junk box) on the far end yields no reflection. It is really nice to be able to keep an eye on the system with the TDR and make sure nothing gets broken. So far - the results are just as predicted listening to W1AW on 1802.5 and WWV on 2.5 MHz. It will be interesting to see how it performs to JA this weekend during the CQ 160 contest. The length of the wire is something around 800 or 900 feet. Tree N6TR _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
