A Synthesized VFO for 5 to 5.5MHz

摘要

Last year I completed the construction of Mike Grierson's (G3TSO) all-band transceiver and I am impressed with the design. With considerable care, reasonably low rates of frequency drift can be achieved using G3TSO's free running VFO. Nevertheless, it is considered that the provision of a 'rock stable' synthesised outboard VFO is required if full use is to be made of an add-on DSP filter. The requirements are as follows: 1. Negligible Drift 2. Minimal Spurious Outputs 3. No Step Size, ie infinitely variable tuning 4. No Back Lash 5. Very Low Phase Noise.