Hi all,

I trying to design a simple BJT mixer for AM receiver. I tried many circuits found on the internet but I want to design my own circuit with the LO injected through the emitter and the IF out through tuned circuit on the collector, but I have quision:

What is the non-linearity that should be used? is it V-I of the base-emitter junction, saturation regon or cutoff regon.

this is just a simple circuit, so i'm worrying about IP3, strong stations ........

any help is very appreciated.​

 

Hello,

Mixing of RF signals is done by the non-linearity of components like diodes.
In the attached PDF you will find some information on it.

The PDF was found on this page from the EDUCYPEDIA on radio circuits:
http://www.educypedia.be/electronics/radiotuning.htm

Bertus