Rap 'n Tap
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From: John Davidson
Date: 8/28/00
Time: 1:38:13 PM
Remote Name: 206.16.140.254
Kelly, As Larry says, I wouldn't think you should split the antenna in the middle as a dipole, but you can take your downlead from the middle without splitting it. I have done that and it works fine. That should slightly change its impedance, but not its sensitivity.
You can understand these antennas better if you think of your downlead as the sensitive part, the vertical antenna and your horizontal "antenna" as a capacitive "top hat". You wouldn't want to shield a vertical radiator.
Also antennas are so lossy (they re-radiate) that I don't think you benefit much from wire bigger than #20 or so. Big antenna wire is like plugging up a pin hole in a can with a bullet hole in it.
And Dennis, connecting the antenna to the insulator is mainly a mechanical issue depending on the kind of insulator you use. The insulator is more important on the far end of the antenna, where voltages are a little higher. On the downlead end, insulators are not too critical. I would avoid much coiling that makes a coil of insulated wire around the insulator. You might just pass through the insulator and wrap around it with a second piece of wire. _J_