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#1
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Is there a difference between antennae used for hand held scanners and base
station scanners? I seem to recall something about it and I'm foggy on the details. Any links would help. Thanks, BJ |
#2
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what do you mean difference?
size wise yes! mike "plushbee" wrote in message ... Is there a difference between antennae used for hand held scanners and base station scanners? I seem to recall something about it and I'm foggy on the details. Any links would help. Thanks, BJ |
#3
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This is going to probably sound stupid but something in the volts or watts
or whatever. Like i say, any links would be much appreciated. I don't expect an enormous explanantion. I'm really new to this and my local radio shack doesn't know much. Thanks "mikeFNB" wrote in message ... what do you mean difference? size wise yes! mike "plushbee" wrote in message ... Is there a difference between antennae used for hand held scanners and base station scanners? I seem to recall something about it and I'm foggy on the details. Any links would help. Thanks, BJ |
#4
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Antennas for handhelds are usually "rubber ducky" style, that is, short (6"
to 9"), rubber-covered, flexible antennas. They are generally designed for a wide range of frequencies, and as such, generally exhibit mediocre performance. Base antennas vary greatly in style, but are much larger and require mounting to a mast of some sort. Since they are mounted at some distance from the receiver (usually outside), a length of coaxial cable is needed to connect them to the radio. They generally perform MUCH better than handheld antennas. Besides being cut to resonate at the frequencies of interest, all antennas require a RF (radio frequency) ground of some sort to be effective. Handheld antennas rely on proximity to your body for RF grounding, which is not a very effective way to ground an antenna. Vertical base antennas often use radials (multiple horizontal or downward pointing elements) for their RF grounds, which allows them to be tuned much more effectively, and therefore more efficient with well-controlled radiation patterns. These concepts are just the tip of the iceberg. There is a lot of science and experience involved in proper antenna design...far beyond what I could easily describe here or understand myself. Ratings for power capacity are irrelevant for scanner use (receive only), but for transmitting applications, base antennas are almost always rated for higher transmit powers. Handheld antennas are generally rated in the 5 to 10 Watt range, while base antennas can be rated anywhere from 50 Watts to thousands of Watts depending on the design. - Doug "plushbee" wrote in message ... Is there a difference between antennae used for hand held scanners and base station scanners? I seem to recall something about it and I'm foggy on the details. Any links would help. Thanks, BJ |
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