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Pointing antenna at plane!

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Old 10-29-2005, 03:20 PM
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Wully
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Default Pointing antenna at plane!

I was making my normal approach with my 60 size P-51 last Sunday when about 10 feet above the runway the plane nosed over and went down. My friend who I fly with frequently said I got a hit from the cell tower which is about 1000 yards away forcing the elevator down[]. Other pilots have claimed this as well. There was no wind and my speed was fine. One member said I was pointing my antenna toward the plane and that would make the signal distorted possibly causing this to happen. Has anyone ever heard this?
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Old 10-29-2005, 03:31 PM
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Default RE: Pointing antenna at plane!

What brand and model are your transmitter and receiver? It sounds like you were fairly close to the P-51.

I have heard of the recommendation to not point the antenna years ago, but I think new radios (within the last 10 years) are lots better in this regard. Personally I have tried to break myself of pointing the TX antenna directly at the plane, but sometimes it is hard.
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Old 10-29-2005, 06:00 PM
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Wully
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Default RE: Pointing antenna at plane!

I have a Futaba T6XA and a Futaba 127DF receiver.
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Old 10-30-2005, 09:29 AM
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Default RE: Pointing antenna at plane!

I have that exact combo too on channel 41 without glitches or other problems. I would guess it was not just pointing the antenna at the plane, but that is just a guess on my part![]
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Old 10-30-2005, 01:23 PM
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Default RE: Pointing antenna at plane!

Some areas have inherent frequency problems, gliches caused by outside sources, etc. My local field has a problem with Ch29, more planes on that channel just tend to have problems. Check with others at the club on your same channel if they have had similar interference. You may need to change channels.
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Old 11-01-2005, 12:17 AM
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Default RE: Pointing antenna at plane!

The signal strength is weakest at the tip of the antenna but it is stil there. I have flown my plane around and have pointed the antenna at the plane with no problems. I would suggest some other problem caused the fault.
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Old 11-01-2005, 12:02 PM
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Default RE: Pointing antenna at plane!

The weakest reception is the TX antenna pointed at the aircraft and the RX antenna perpendicular to the TX antenna.
The best reception is the TX pointing away from the plane and the RX antenna is point at the TX
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Old 11-01-2005, 01:01 PM
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Default RE: Pointing antenna at plane!


ORIGINAL: Geistware
The best reception is the TX pointing away from the plane and the RX antenna is point at the TX
Not true.

The end on view of the RX antenna is also the worst for reception. The best reception is when the antennas are parallel to each other pointed in the same direction (either horizontal or vertical).

Monopoles antennas have a reception pattern kind of like a donut, where the axis of the donut hole is aligned with the antenna. TX and RX properties of an antenna are the same, so you have the same pattern whether it is a receiver or a transmitter.
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Old 11-01-2005, 01:41 PM
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Default RE: Pointing antenna at plane!

at http://www.qsl.net/k5bcq/MS2K/MS2K.html you'll find some very nice simulations of radiation patterns for RC TXs. but be patient as the images can take a while to load...



dave
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Old 11-01-2005, 03:22 PM
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Geistware
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Default RE: Pointing antenna at plane!

In theory, I don't disagree with you.
I learned that at school as well.
What I have found in practice with JR and Futaba equipment is that the range when parallel is a lot less than when the RX is the stem of the T. I don't know why. Just have had this more times that not. I have seen 4 newbies to gas not fly because there range when side on to the plane was greatly reduced. The only exception would be if the mass of the engine was strengthening the signal to the RX but I doubt that.

Like I said, I learned that in school as well but not seen it in practice at the field.

ORIGINAL: mr_matt


ORIGINAL: Geistware
The best reception is the TX pointing away from the plane and the RX antenna is point at the TX
Not true.

The end on view of the RX antenna is also the worst for reception. The best reception is when the antennas are parallel to each other pointed in the same direction (either horizontal or vertical).

Monopoles antennas have a reception pattern kind of like a donut, where the axis of the donut hole is aligned with the antenna. TX and RX properties of an antenna are the same, so you have the same pattern whether it is a receiver or a transmitter.
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Old 11-02-2005, 03:54 AM
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Default RE: Pointing antenna at plane!

ORIGINAL: Geistware
I have seen 4 newbies to gas not fly because there range when side on to the plane was greatly reduced.
How was the range test being done? If the antenna was down than the radiation pattern would probably be significantly different than normal flying condition so the basis of your observations would be a flawed example.
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Old 11-04-2005, 11:06 AM
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Default RE: Pointing antenna at plane!

I have the 6EXAS and have noticed in close proximity to the plane, (about 2-3 feet) the servos glitch. A little further out they are fine.
Strange ain't it?
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