>I need a simple broad band receiving wire antenna, from 3 to 30MHz.
>Something other than a Beverage.
>Any suggestions?
>Ted Leaf, K6HI
Hi Ted!
I haven't seen any answers to your antenna question on the reflector, so
here's mine.
I'm a big fan of multiband wire antennas. I don't think you can beat the
bang for the buck. Try a 130-150 ft long doublet fed with TV twinlead for
all frequencies from 3-30 MHz.
For *RECEIVE ONLY* Feed it about 1/3 from one end to minimize impedance
variations. Use a 300-to-75 ohm transformer from the TV section of your
favorite department store and connect either 75 or 50 ohm coax to your
receiver.
For higher performance and to also be able to transmit, feed the doublet
in the center. This requires an antenna tuner with a built-in balun (open
wire terminals on back). If you have to pass by much metal to bring it
into the shack, connect a shielded-parallel line made from 2 pieces of
rg-58 coax as shown in the ARRL antenna book. Or you can spend about $50
for a remote balun to transition to a single piece of coax to your rig.
Both methods will prevent interaction as the feedline passes by metal
objects.
I use the shielded parallel line method with good success. Twist the
shields together at both ends, ground them at the tuner, and leave them
floating at the other end. Use the center conductors like open wire line.
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