My Diversity MEPT uses two oscillators on the same frequency each with Frequency Shift Keying 180 degrees out of phase. This results in a box appearance when receiving both signals, resembling a string of Paper Dolls (Origami).
The two oscillators are locked in frequency by exploitation of the cross coupling inherent in the construction of CMOS Gates.
The 'G3ZJO Lock' is described on my companion blog. Radioman
