Dave wrote:
...
http://www.new-tronics.com/main/html/mobile_vhf.html
When this antenna was changed for a 1/2 wave a lot of coverage was
lost. This was before cell phones so I had to start using pay phones a
lot.
The one with the center coil is a collinear. It is 2 stacked verticals
with a "delay" between.
If I remember correctly, from running comparisons thought antenna
prediction softwares, 1.5db is about the most "gain" which can,
theoretically, be had between a 1/2 and a 5/8; and, not even "all that
gain" (i.e., max 1.5db) is gained in such a narrow point or swath of
pattern so as to account for "a lot of coverage lost." And, rarely, if
ever, is the theoretically reached, in my humble experience.
Something is obviously wrong with that whole statement ... perhaps a
"chit poor" 1/2 is being compared to a reasonable performing 5/8?
Regards,
JS