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.
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