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From: DD3LY / Andreé
Date: 07 Oct 2001
Time: 09:22:40
Remote Name: 217.1.39.234
There is a much easyer way (read my first reply): If you build up the antenna as a "J-pole", you just need some wire, some isolating spreaders (made from lucite rod for example) and a FT140-43 ferrite toroid. With a VSWR-meter you can match the antenna very easy. This is the cheapest and easyest way to match a halfwave vertical. It will take one hour only, if your halfwave vertical is erected. The J-pole is just a halfwave vertical up and a quarterwave parallel line connected to its lower end. The quarterwave parallel line may be bent 90 degrees from the radiator. The conductors of this line are connected at the opposite end. Use a coax line which starts at the transceiver, goes to the VSWR-meter, winds itself several times through the mentioned ferrite toroid and ends into two aligator clips. Connect each clip to one of the conductors of the parallel line. Start at 20 percent of the whole length from the point where the conductors are connected. Key the transmitter, look at the VSWR and shift the clips parallel to a point where the VSWR is next to 1:1 (stop transmitting while shifting). That's it. This is sooo easy, you will get satisfaction 100 percent. You can use this type of feeding for QRO as well and it is very high efficient. For further questions: andree.knott@t-online.de