On 4/8/14 4:25 AM, john@kk9a.com wrote:
I just read the Joel Hallas, W1ZR article - "The 43 foot vertical monopole
- What's the magic?". It was very interesting! The coax losses are worse
than I imagined, up to 8dB though 100 feet of RG-213, and as my model
showed the radiation is very high above 20m. Certainly a relay to
electrically shorten the antenna would help 15m and 10m.
I'm of the general opinion that one should be putting the matching
components at the feedpoint of the antenna (base in the case of a
vertical), so the coax loss isn't going to be a factor.
However, the radiation pattern from an overlong antenna is an issue.
This brings up an interesting idea. What if lengths of elements between
traps and trap design were not driving towards getting a 50 ohm match at
the feedpoint, but rather, just getting the effective radiator length right.
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