I was building a receiver circuit ( superhet) for shortwave radio, primarily for 20m ( 14mhz) band. The circuit uses 3N211 or 40673 mosfet for mixer. However I have only these components available at my disposal :
BC547----- BC557------ 2N2222------- 2N3904
I searched this website for mixer circuits using BJT :
Now my question is
1) Will this circuit suffice practically
2) Since 40673 mosfet is unavailable, can any of the above mentioned bjt be used in its place ( No other component / IC whatsoever is available at my place) ?
The block diagram of the above mentioned scheme is below :
For additional details see :
( I have decided to remove BFO since I do not plan to communicate on Morse Code. Also IF filter will be used)
Another of my concerns is that the circuits given in the above mentioned link are simply too complicated for me to understand. So if I substitute simple textbook circuits ( or those found on online tutorials) with required component values ( For example as local oscillator, I plan to use a Hartley oscillator with variable capacitor and an active op amp filter ) will this suffice or I need to stick with the same circuits ?