However, while it will certainly outperform the circuit in question, a proper superhet is really the way to go - but a direct conversion receiver like this can certainly perform.
They are parallel, but usually the resistor value is so high that its impedance can be ignored. Winding around a resistor is just a convenient way to make a coil. You can ignore the resistor.
Which one? In the whole design I'm using only two types of cores except for the BFO. I'm using Amidon FT-37-43 for the chokes and the filters & oscillators are Amidon T-37-02. The BFO needed to run at the 2nd IF which is around 2MHz (low freq) so I'm using Amidon T-80-06 (yellow).
I would not use a resistor. It will work in very low signal levels but the ferrite cores (FT-37-43) have self shielding properties. It enables you to get away with less shielding.
That's not the woodpecker. If it is, there is something seriously wrong with your receiver. The woodpecker has a much slower repetition rate. The SSB audio sounds normal though.
That's not the woodpecker. If it is, there is something seriously wrong with your receiver. The woodpecker has a much slower repetition rate. The SSB audio sounds normal though.
Thanks kchriste. Well I sure thout that was the woodpecker. Seems like the same one I've been hearing for years but who knows. Might be the HAARP. It uses similar technology.