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Windom for 80 - 10. Choke or not choke?

Jan 25th 2018, 15:17

W1VT

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
They can be both right, depending on the situation. Sometimes it is useful to have a choke, as you may get a better pattern on a higher band. Or it may be worse, depending on what you need. RF chokes are especially useful for getting rid of common mode noise from the ham shack--it isn't a good situation when you can hear computer noises on the ham bands--noise from a "grounded" computer won't all go to ground, unless you have an extensive radial system. Ground is more like a 50 ohm shunt, rather than the 0.0 ohm theoretical ground we think of.

Some lucky hams do get better performance without a choke. It is likely that they don't have a computer or noisy electrical and electronic devices in their homes. But not many people would be comfortable living with the technology of the 1960s. I like to see a weather map before I go outside to do major antenna work. These days I can get a pretty good idea whether or not a fast passing thunderstorm system will be a problem, or even if the weatherman thinks there may be a possibility of a pop up thunderstorm in the afternoon.

Zak Lau W1VT
ARRL Senior Lab Engineer
Jan 25th 2018, 15:22

N1AUP

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
I'm putting up a home brew WIndom antenna. I read the following articles to figure out how to put one together.

http://www.packetradio.com/windom.htm

and

http://www.hamuniverse.com/k4iwlnewwindom.html

The second article says that you need a choke on the coax feedline to set up a vertical radiating part of the antenna.

The first article says that the choke isn't necessary. In fact, it says that the choke will make the antenna perform more poorly than if you leave it off.

Which is correct?

Thanks

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