The "Type 3" circuitry incorporates all of the design refinements from the evolution of the previous
Click here for component descriptions and sources, and please browse all of the "preselector"
pages on this site to get a full understanding of the development of this final version. If you are not
too comfortable with 'scratch-building' I suggest you visit my page on the MFJ-956. Construction
Note: There are four (4) main sections to this project; 1, Passband Filter; 2, Notch Filter; 3, Tuner; 4,
Amplifier/Attenuator. With the exception of item 1, any of the other sections may be omitted.
Additionally, the builder may elect to make all of the sections 'switch selectable' IE; attenuator,
preamp, notch so that they may be 'switched out' of the circuit or 'switched in' as needed. Use your
imagination and build the preselector that suits your needs.
Preselector Type 3A