At 06:54 AM 8/1/96 -0600, you wrote:
>Dave Raymond-CSUS04 wrote:
>
>However, after
>> reading the TH7 stacking info in the recent NCJ, I'm not so sure 40'
>> spacing is the way to go.
>>
>> I've not gotten into using the various modeling software (yet).
>> Anybody out there tell me what the front to back ratios look with this
>> spacing? Are they really poor? How about 30' spacing? I could go
>> either way.
>>
>> Any comments, ideas, or recommendations??
>>
>> 73....Dave Raymond/WA0FLS
>
>Dave,
>My experience with front-to-back says that more is not always
>better. It is sometimes beneficial to put out a good signal off the
>back of the antenna. This is especially true in the midwest, and
>especially true in domestic contests, where it is really an
>advantage to be loud on both coasts at the same time, rather than
>just extra loud in a single direction. Helps keep the competition
>off your frequency, too ;-)
>
>If it were my antenna system, I'd be more concerned about maximizing
>forward gain and/or filling in the radiation pattern at advantageous
>angles. I say let the f/b take care of itself.
>
>Tony KM0O
>
>
I would think that the effort and cost involved would not be worth the small
amount of gain in one direction. (see what does a DB cost discussion)
After looking at doing the same thing several years ago (without the help of
a good software package) I felt it would be better to take the second TH7
and put it either on a new tower or opposite of each other on the same tower
if room was in issue. Feeding them seperately and using a coaxial relay or
a coax switch to be able to switch between the two beams going in opposite
directions. I used an old DowKey relay (remember those?) on a foot switch
to go either east or west. Played well in the 80 and 81 SS. I opted for
the second tower even if it was only up 50 feet. That gave me the option of
pointing it anywhere the propogation was favoring while still maintaining
the other to the maximum rate zone. As soon as the propagation changed then
I would switch beam headings. Now, this is ideal in Kansas because we are
half way to nowhere. That idea might not work in other areas. Just my two
cents
Lee
k0wa@southwind.net
"kick the tires and light the fires.....its contesting weekend"
Lee Buller
k0wa@southwind.net
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