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Old November 7th 10, 08:08 PM posted to rec.radio.amateur.antenna
David David is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 37
Default Which is better: 5/8 wave vertical or J pole?


Which antenna is better: 5/8 wavelength vertical or a J pole?

Frequency of operation is 145 MHz = 2 metres.

The 5/8 wavelength vertical has a loading coil. There are losses in the
coil.

The J pole has a quarterwave matching stub. The matching stub provides an
out of phase current which means that there is a cancelling field close to
the radiating element. Also the J pole is end fed, which means the
transmitter is not connected directly to a maximum current point.

Does the J pole have a disadvantage because of the cancelling field from
the matching stub and the fact that it is end fed?

Also consider gain and angle of radiation.