Rod Ehrhart/DXE wrote:
>
> The single Active Receive Vertical Antenna is designed as a no-gain antenna
> with a flat response across several octaves of the HF
> spectrum.
It has zero dB voltage gain, but a substantial power gain, because of
the difference between the input and output impedance.
The response is not flat across several octaves. The instructions
specifically direct the user to install jumpers to tune it to
a particular band. If I am misunderstanding the instructions,
maybe you can enlighten us.
This allows the Active Vertical to receive low angle signals and noise
at a lower total level, thereby improving the
> signal to noise ratio (s/n).
This statement is misleading. The active circuitry provides
enough power gain so that the 102 inch whip's noise can overcome
the receiver noise. Thus it improves the signal to noise ratio
compared to connecting the whip directly to a 50 ohm receiver.
In this limited sense, it improves the s/n ratio.
However, the resulting S/N ratio won't be any different than,
for example, tuning the 102 inch whip with a loading coil,
and connecting it to the receiver without a preamp.
> Without a description of the trouble you are having, it is difficult to be
> specific. Therefore we believe this general information
> regarding the DX Engineering Actives, and the nature of receiving antenna
> systems, might be helpful.
> Rod Ehrhart - WN8R
Again, the DXE active vertical does what is supposed to do, albeit
at a fairly high price, IMHO. However, it shouldn't be expected
to perform magic. A vertical is a vertical.
Rick N6RK
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