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Old April 28th 07, 04:43 PM posted to rec.aviation.homebuilt
RST Engineering
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Default Antenna Installation on Longez


"Glennbob" wrote in message
s.com...


THAT'S JUST THE PROBLEM. . . .THE JUNCTION BEING IN THE CENTER
OF THE WING.


In the first place, don't type all caps.


I DON'T WANT IT IN THE CENTER OF THE WING. TOO MUCH
METAL THERE FOR DISRUPTION.


Look at a Cessna. The whole damned vertical stabilizer is metal and they
run the center of the antenna right onto the surface. It isn't the CENTER
of the antenna that is critical, but the ends. You can have metal near the
first third of the antenna from the center without too much of a problem.

SO . . WITH THE CENTER OUTBOARD OF THE
FUSELAGE, . . HOW DO I GET THE COAX BACK TO THE FUSELAGE WITHOUT
DISRUPTING THE WING SHAPE ?


Simple. You don't.



ANSWER : . . . I DON'T ! ! THOUGH I KNOW IT'S NOT THE BEST
WAY, . . IT SEEMS THIS IS WHAT THE EZ COMMUNITY HAS BEEN DOING FOR A
WHILE AND THEY ALL SEEM SATISFIED WITH IT,


That's because that's how I taught Rutan to do it nearbout thirty years ago
and he passed it on in his drawings.


. .BUT AFTER READING AN
ARTICLE BY JIM WEIR,


....and taking what you read out of context ...


. .AND SEEING A SCHEMATIC THAT HE HAD SHOWING
SEVERAL ANTENNAS ON EACH EXTREME WING AREA, I WANTED TO DO IT THAT
WAY FOR BEST RESULTS.


....and given no constraints like ease of installation or repair, that's how
I'd do it. Any aircraft is a series of compromises flying in loose
formation.



BUT IT SEEMS THIS IS NOT GOING TO BE WORTH THE
EXTRA EFFORT. SO . . . I PLAN TO USE THE VOR ANTENNA THAT IS ALREADY
GLASSED INTO MY CANARD


Wasn't that antenna the one that was only about 10" long each side? That's
going to be a lousy VOR antenna.




AND I PLAN TO INSTALL A SECOND ONE FOR THE
GLIDE SLOPE , . .SINCE IT IS MUCH SHORTER ( ABOUT 7.5 " ). I PLAN TO
INSTAL IT RIGHT NEXT TO THE VOR ANTENNA SINCE I DON'T WANT TO USE A
SPLITTER.


Jeez, I guess you just don't want to listen or follow drawings. Now you ARE
putting the ends of an antenna near metal, in this case both the VOR antenna
AND the ironmongery in the aircraft.


- - AGAIN, . .READING THE ARTICLE FROM JIM
WEIR, . .SHOWS THAT THERE IS AN AUTOMATIC 30% LOSS OF SIGNAL WHEN
USING A SPLITTER.


I'm glad you aren't in my class. Reading out of context like this
guarantees you an F for the semester. Jim NEVER said that there was a 30%
loss when using a GLIDESLOPE splitter. Now if you are using a splitter for
two VORs, yes, there is that loss. However, I've been flying aircraft for
forty years using splitters and as yet, not a problem with range. I'd never
show people how to make a splitter if I thought there was a problem.
Besides, even IF there was some loss in a glideslope splitter (which there
isn't), if a 30% loss to a 10 watt signal at 5 miles is a problem, you've
got more wrong than a splitter can cure.



IF YOU'D LIKE PICTURES, . . SEND AN EMAIL TO



I'll bet it isn't a pretty sight.

Jim