开云体育

Touching the raduino crystal does indeed change the pitch of the tone of the birdies.
However, when I connect the antenna, and tune to a cw station, then the pitch also changes when I touch the crystal.
I think this is simply because the DDS output frequency is slightly changed when the crystal is touched.
So ANY received signal (birdies as well as 'true' signals) will be affected when the crystal is touched.

So i.m.o., the simple fact that the pitch of the birdie changes when the crystal is touched, does not necessarily mean that the birdie is coming from the crystal itself.