cuhu... wrote:
Just what do they mean by Active? (hey,I am dumb) Does it mean it is
Active because they use a battery and the battery "Activates" it?
cuhulin
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And active antenna is an antenna with a built in amplifier, or "active"
component. For example the AmRad active antenna uses a special
FET (Field Effect Transistor) and is "as effective" as a ~100' long
wire.
For low frequencies, like a 60KHz signal, even a 100' antenna is short.
The AmRad, DA100-E, "North County" and even the "Tiny Tenna"
all use transistors to convert a small 36" or so, wire into a usefull
antenna. The Tiny Tenna is the simplest, but even it will do a decent
job far from any MW (AM 540~1600KHz).
Loops can be passive or have amplifiers, and those with amplifiers
are termed active.
For RF reception from 500KHz through ~30MHz I prefer the common
~100' wire antenna. For MW DX work a loop is hard to beat. For
LF work, 500KHz and lower, an active antenna is the only practical
way to go.
Terry
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