Maybe his secret is a preamp cooled with liquid helium! ;-)
Seriously, there are preamps operating at 70 degrees F (for example) that
have less than a 1 dB NF at VHF. They are usually mounted at the feedpoint
of a high gain array, because of feedline loss.
Today, I have the type of terrible cold (hay fever?) that seriously
interferes with one's thinking but I still have an open mind about this
subject. Waller Flags fascinate me. I'm in learning mode and watching this
thread closely.
>From everything I have read in the past about the WF, it'll equal a
one-wavelength Beverage in only 30' of space. And it's tough to rotate any
Beverage for 160. How a WF would compare with my Beverages in this quiet
rural location, I can't say.
73, Mike
On Sun, Sep 6, 2015 at 1:53 PM, Tom W8JI <w8ji@w8ji.com> wrote:
> ... a modest size WF would need about 40 dB of gain
>>
>
> ... would require a 1 dB noise figure front end. That's about 35 deg K
> noise temperature.
>
> 40 dB gain in front of a receiver is pure fantasy,...
>
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