At 08:46 AM 2/1/01 -0800, you wrote:
snip.
>
>
>I have long wondered why the reflector on a yagi is longer than the driven
>element and why the directors are shorter. Also why do multiple directors
>increase the gain but multiple reflectors do not?
This is incorrect when speaking of multi (high density) elements
or optimum elements per array wavelength.
When you have multiple directors then multiple reflectors
DO assist the gain as well as INCREASE the front to rear/back
..... especially when TOTAL BAND SPREAD is considered.
Reflectors in such cases are NOT always longer than the driven element
( must not exceed 3 in number ,total 13 elements max per wavelength of array)
......because the self impedance of an element is of more importance than
physical length
Seems like this should be a subject other than 'shadowing'
Art Unwin
I suspect it has something
>to do with the geometry and transit time but its only my WAG. Hopefully
>"several technically will-versed people" will enlighten us!
>
>k7puc
>
>
>
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