Quote:
Originally Posted by sunrisor
That's something else I didn't know. So you're saying the the gain to the rear of the antenna may reach farther with a medium antenna?
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Maybe, maybe not...
When perusing an antenna spec sheet, one would hope to find a specification for forward gain, front-to-back ratio, half-power beam-width, SWR and a polar plot. In a perfect world, you would get to see these specs for each of the channels that you're interested in... (In the consumer grade antenna world, not all of these specs are provided.)
How well an antenna receives from the rear can be estimated by subtracting the front-to-back ratio from the forward gain.
Example: An antenna with a forward gain of 10 dBd and a F/B of 15 dB would be expected to have a net gain of -5 dBd to the rear. In a case where there is a moderate to strong signal from the rear, this small amount of attenuation would not be enough to prevent reception by itself.
You'll find that most directional antennas will have some useful reception capability to the rear.
In your case, real CH-8 & CH-47 are certainly strong enough to expect good reception even when the antenna is pointed in the opposite direction.