How to make the Mixer work?

I have a Level 7 mixer. I give same input to both L and R of amplitude 25mV and frequency 20MHz. My CRO is 100MHz one. Shouldn't I get twice the frequency as output? I do autoscale and get no signal found. Please check your probe connections. Then I play with the amplitude a little at there is something on the display. But not as expected. Where are things going wrong? I am totally new to all this. Plz help! Thanks

Diode mixers need a high LO level to turn on the diodes. Check the data sheet. I doubt 25mV will be enough.

Keith

---------- Post added at 09:47 ---------- Previous post was at 08:17 ----------

Reading this may help:

http://www.minicircuits.com/app/AN00-010.pdf

For Level 7 you would be using around 7dBm of LO level which is around 500mV RMS (not 25mV).

Please mention the part number of mixer what you are using, then it will be easy to answer... :)