The best phase noise and phase shift stability will be achieved by not using a bandpass filter to extract the 10MHz signal, but by using a low pass filter with low phase shift at 10MHz to eliminate the higher harmonics, supplemented with high Q series tuned traps at the fundamental (5MHz) and 5th harmonic etc to shunt these undesired harmonics to ground. The high Q series tuned traps will have low phase shift and associated phase shift tempco at 10MHz.
This works best when either a common gate or common base bipolar transistor is used to amplify the output (as in the Wenzel application note) before driving the filters. Whilst using a bandpass filter is the obvious solution it will have a large group delay and phase shift tempco which will increase the phase shift instability due to temperature changes. Bruce _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
