All folk,

I got some of amplifier TV antennas from consumer product in the markets.
None of them works well in all local TV stations. What are going on in these
products in the markets? They seem use wrong theory or don't use any theory.
It becomes just a toy on the top of the TV.

Amplified indoor RC antennas are, in my experience, a rather
poor-performing product family in general. This seems to me to be a
fundamental problem - it's not just an implementation glitch with one
or another variety.

The problem is this: in many indoor situations, there just isn't
enough clean, reflection-free RF for many stations present, above the
local ambient noise floor. The signal present is badly contaminated
by noise, and by reflections of the signal from nearby buildings
(multipath), even before it hits the antenna. In these cases, it
really doesn't help matters all that much to amplify the noisy/ghost-
filled signal before sending it to the TV set - you boost the ambient
noise and the ghosts, along with the desired signal.

In some cases, with some TVs, I gather that the amplification can help
somewhat (some TVs seem to have poor RF front-end gain), but in other
cases the amplification either doesn't help, or makes matters worse
(by overloading the TV's tuner with other, stronger signals on nearby
channels).

There's not really a good substitute for an antenna with good
directional gain, mounted up as high as is practical on the roof, and
aimed properly.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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