Lycosaurus

Lycosaurus

Well Known Member
A couple of months ago I installed an Archer clone (right-wingtip antenna) in our RV-9A. I guess I managed to do a pretty good install since I can get a signal from the CYOW VOR (Ottawa):

108 nm (10,500 ft, moving away from the VOR)
135 nm (10,500 ft, moving towards the VOR)

Wired to a 3dB splitter, SL-30 receiver.

Have not tried finding the limits for different headings since we were on cross countries ... on a mission.

Anybody else have distance reports on their antenna installation?
 
In my RV-8, I can get about 70 miles with the Archer in the right tip connected to the 430W at 5,000'. (I haven't taken the time to try it while higher up - it was just an interesting exercise one day while tooling around.

BTW, the "Nearest" function on the 696 is a great way to do this test very easily. Punch up "Nearest" VOR, then just start dialing in the frequencies for increasingly distant stations until you can't get the next one. Sort of like doing those hearing tests....

Paul
 
On my way back from Oshkosh

Recieved aylmer VOR from over the Detroit River at 3500 ft. I think that's 82 nm. I was surprised I got the signal.
 
Lycosaurus said:
A couple of months ago I installed an Archer clone (right-wingtip antenna) in our RV-9A. I guess I managed to do a pretty good install since I can get a signal from the CYOW VOR (Ottawa):

108 nm (10,500 ft, moving away from the VOR)
135 nm (10,500 ft, moving towards the VOR)

Wired to a 3dB splitter, SL-30 receiver.

Have not tried finding the limits for different headings since we were on cross countries ... on a mission.

Anybody else have distance reports on their antenna installation?
Click to expand...
Alfio:

Back in 2000 I gave a talk on antenna patterns and reception.
Find a HAM radio Operator with a Field Strength (FS) meter and have him do a walk around your plane...
Same distance out from the antennas - About 20 to 30 Feet and
PLOT the signal strength for every 15 Deg of rotation around the antenna.
What you will find is you have a STRONG signal on the side of the plane where the antenna is located and
AN EXTREMELY WEAK signal 180 Deg opposite the antenna.
It is also going to be weak off the ends of the antenna.
The metal of your wing and the polarization of the antenna cause these problems.
Believe it or not, one of the best VOR antennas is the CAT WHISKER design mounted next to the area of tail wheel . VOR's are ground based and the antennas should be looking in that direction. And the bottom of the plane acts as a ground plane to improve the radiation pattern.


Barry
 
Barry_Barry said:
Alfio:

Back in 2000 I gave a talk on antenna patterns and reception.
Find a HAM radio Operator with a Field Strength (FS) meter and have him do a walk around your plane...
Same distance out from the antennas - About 20 to 30 Feet and
PLOT the signal strength for every 15 Deg of rotation around the antenna.
What you will find is you have a STRONG signal on the side of the plane where the antenna is located and
AN EXTREMELY WEAK signal 180 Deg opposite the antenna.
It is also going to be weak off the ends of the antenna.
The metal of your wing and the polarization of the antenna cause these problems.
Believe it or not, one of the best VOR antennas is the CAT WHISKER design mounted next to the area of tail wheel . VOR's are ground based and the antennas should be looking in that direction. And the bottom of the plane acts as a ground plane to improve the radiation pattern.


Barry
Click to expand...

Guess that is why my Archer nav antenna works as nicely as it does. The VOR is most likely to be in the area of strong reception for the antenna. :)
 
My experience with these over the decades has been around 75-90 miles for a VOR at an average normal RV altitude. The whiskers to work better no doubt, but the wingtip ones work pretty darned well given the fact that most of us rarely use them...GPS is becoming king!

Just my 2 cents as usual.

Cheers,
Stein
 
I am just trying to wrap my head around how a FS meter is going to show me anything on a receive only VOR/LOC/GS antenna???
 
High Power YOW VOR

Note: I just found out that YOW is a high power VOR, though I can't substantiate it. The range for some other VORs is much lower at about 80 nm or so when I flew yesterday (we were at 5000 ft this time though).

Will check range of other VORs at higher altitudes next time we have a cross country flight.

P.S. Some people in the know indicated to me that VORs normally transmit at 25W, while high power VORs (like YOW) transmit at 45W).
 
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