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Old April 19th 08, 06:02 PM posted to rec.radio.amateur.antenna
Antonio Vernucci Antonio Vernucci is offline
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First recorded activity by RadioBanter: Jun 2006
Posts: 395
Default Efficiency of 200-ohm hairpin matching

After running the required simulations it was possible to conclude the
following:

- the antenna impedance can clearly be transformed into 50 ohm or into 200 ohm
by just changing the driven element length and the hairpin length. By selecting
the proper lengths, an identical SWR curve can be obtained for the two cases,
this meaning that the matching system impedance has virtually no influence on
the SWR bandwidth of the antenna under simulation

- however, for a given RF power, in the 200-ohm case the RF current in the
hairpin is about 1.8 times higher than in the 50-ohm case. This means that in
the former case the power lost in the hairpin ohmic resistance would be about
3.2 times that of the latter case.

73

Tony I0JX