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Old 11-01-2007, 01:25 PM   #3 (permalink)
jeffk
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Honestly, it really shouldn't matter at all which way you have it. To get the maximum signal strength between any receiving antenna and any transmitting antenna, the two antennas should be aligned along the same axis. That is, they should be pointing the same direction. We radio folks refer to this a s "polarization". If your antenna on your model is vertical, it will "hear" your transmitter best if the TX's antenna is also vertical. Likewise with a horizontally polarized antenna, but here we introduce another axis: azimuth (the direction the tip of the antenna is pointing).

If your antenna on the TX is horizontal, and pointing at, say 270 degrees (due West), then your receiver will hear it best when it's antenna is also horizontally polarized and pointing at 270 degrees. Signal strength is always lowest when the transmitting antenna and the receiving antenna are "cross-polarized" or put another way, perpendicular to each other.

The thing with antenna placement is, your model's position (and therefore, the antenna's position) is constantly changing as it moves and maneuvers through the air. Therefore, the orientation of one antenna to the other is constantly changing, and so the received signal strength at the model is constantly fluctuating. So, it really matters very little which direction your transmitting antenna is placed. The radios are engineered so that in a worst case scenario (i.e. TX and RX antennas perpendicular and model at outside edge of range) the radio signal strength will be sufficient to maintain control of the model.

Proper antenna / receiver placement in the model will have a much bigger effect on range and signal strength than whether or not your TX antenna is horizontal, vertical, or somewhere in between. Ensure that your antenna is as exposed as you can get it and keep it away from conductive surfaces that can block reception and you'll be fine.
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