Directional base antenna
Here are 2 I use that
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Grove Enterprises SCANNER BEAM III
SCANNER BEAM III
ANT03 $69.95
Grove’s highly-regarded Scanner Beam has been improved with higher gain, and is being released at a special introductory price! Mount it high and in the clear for full-spectrum VHF/UHF frequency coverage from 30-1000 MHz! Hear law enforcement agencies, firefighters, emergency medical teams, aircraft, marine radio, trains, FM and TV broadcasting, business band, federal agencies and more—up to 100 miles away!
Lightweight and compact, all parts are included—balun transformer with F connector, offset boom, U-clamp. No assembly required—just rotate and latch the elements into place. Point it in any direction for maximum reception, or aim it with an inexpensive TV rotator. I
And
Scanner world YAGI-800, YAGI DIRECTIONAL BASE ANTENNA - Scanner World - The Largest Dealer of Scanning Radios in the World
YAGI DIRECTIONAL BASE ANTENNA
YAGI directional beam base antenna for digital and analog scanners.
$59.99 + $11.75 S&H Each
Model Number: YAGI-800
Availability: IN STOCK
ANT2904
HIGH GAIN DELUXE CELLULAR YAGI ANTENNA
FREQUENCY RANGE 750-940 MHz
GAIN 14 dBi @ 855 MHz
VSWR LESS THAN 1.5:1
POLARIZATION VERTICAL OR HORIZONTAL
IMPEDANCE 50 OHMS
MAX. POWER HANDLING 50 WATTS
CONNECTOR N FEMALE (Includes BNC Adapter)
ANTENNA DIMENSIONS: 32"W x 8"H
INCLUDES U-BOLTS FOR MOUNTING (Does not include mast)
Dimensions: Main boom 5' 10"
Longest element 8' 4"
Number of elements: 14
FAQ
Q: What is the beam width of the new Scanner Beam?
A: I can only answer this in generalized terms because with the wide frequency range this beam covers, the beam width varies considerably.
For example, at low band (30-50 MHz) it's essentially omni-directional with virtually no favored direction, but as you increase in frequency, it becomes sharper and sharper (more and more gain). At high band VHF, I'd say that it's probably at least 45 degrees wide for decent reception, while at 800 MHz, the reception drops off conspicuously after about 10-20 degrees. Bob.