Re: RF Clipper Diode Design


They are all pretty close in frequency. Exotic resonators might be needed. And even the 100 W signal would need to be attenuated somewhat. These babies do not have a 120 dB plus instantaneous dynamic range meaning weakest detectable signal at the same time the very strong signal is present within the RF passband of the front end.


On 20200203 01:30:54, Allan Isaacs wrote:
If you get 30 to 40dB skirts from a tuneable bandpass filter wouldn't that
do the job re 100W versus 120KW? You may need a 3-gang tuning 500pF
capacitor and a set of carefully matched coils.
Allan G3PIY
-----Original Message-----
From: [] On Behalf
Of jdow
Sent: 03 February 2020 09:07
Subject: Re: [SDR-Radio] RF Clipper Diode Design
In his particular case replacing the antenna with a paperclip, bent or
would probably work. A large attenuator in the antenna lead would also do
trick. He's not exactly trying to receive a weak signal. It's simply weak
compared to what is around it.
He needs the band stop filter if he wants to wander out to OTHER weak
But 100 W next to 120 kW at 3 km distance is one bodacious humongous
big signal.
On 20200203 00:48:02, Allan Isaacs wrote:
Back in the 1920s and 30s a common problem was reception of weak signals
in the
presence of strong local broadcasts (not that I remember.. I just read
about it).

The answer was to design a proper RF front end with bandpass tuning etc.

There's nothing wrong with constructing a tuneable front end for an SDR.
In fact
the graphical presentation of the spectrum makes it easy to align such a

Combine this with a directional loop antenna and you have a perfect

Allan G3PIY

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