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We've got an awesome buy for you this time! Astatic is an industry leader and they are now manufacturing antennas. This is one of their 4FT dual antenna kits and it includes dual 4FT black antennas, 9FT co-phase coax harness and two heavy duty mirror mounts. This kit includes everything you need for a fraction of what it would cost to purchase it separately. This is one deal too good to pass up!
SKU # AST4FTDL
Features include:
Power rating of up to 1000 watts
Exclusive Linear Load Design
Highest Radiation Efficiency
Frequency Range 26-30MHz (10 and 11 meter)
Fiberglass Reinforced Polymer Resin Core with Polycarbonate Outer Housing, offering superior structural integrity
Enameled 12ga. Solid Copper Wire
36” Tapered Stainless Steel Whip with Corona Ball
Nickel Plated Solid Brass Ferrule System
Truck Tuned for CB – can easily be re-tuned for your vehicle
The LINEAR LOADING Story
When it becomes necessary to reduce the length of a resonant radiator, theory dictates a trade-off in radiation efficiency. For years, antenna manufacturers have conventionally resorted to “eating up” the length (hence the radiating aperture) of an antenna by employing “inductive loading” in the form of coils placed in series with a linear antenna.
This, in fact, shortens the physical length of that antenna making it mechanically manageable. This is deemed a “plus” since the now shortened antenna, when used in vehicular applications, tends to be far less susceptible to damage from tree branches, overhead wires and highway overpasses, just to name a few of the many common hazards.
Series-coiled inductors radiate little, if any, signal. Furthermore, the physical placement of a coiled inductor during the design stages of a loaded antenna is quite critical to the radiation efficiency of the antenna. One must keep foremost in mind that when dealing with quarter-wave radiators, the most common vehicular antenna in use, the lower section does the majority of the signal radiation. Hence, the interruption of the lower extremities (at or close to the base of the antenna) of the quarter-wave with a coiled load immediately detracts from the overall radiation efficiency that would have been possible by smarter design. In addition, the highest RF currents exist closest to the lower extremities of a quarter-wave. This automatically makes a coil inductor a “hot spot” that is vulnerable to heating when carrying high RF currents indicative of high transmitter output power levels. This immediately reduces the duty cycle of the antenna for transmitting high power levels and burnout is eminent.
SKU # AST1K
Only $46.95
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