The TV and FM filter comes from the Progressive Communications Receiver, in most of the recent ARRL Handbooks.
Values used are for the 40 meter band going directly to the bandpass filter, without using the RF amplifier, as suggested by the Progressive Communications Receiver article.
The TV and FM Filter is recommended if you live in a large city, but are not necessary if you are free of high wattage commercial broadcast stations.
An alternative is to use a single-pole tuned filter, with a variable capacitance across the coil to provide some manner of matching to different antennas. The single-pole filter will provide a low loss filter that will prevent the RF amplifier from amplifying every signal out there and making the second bandpass filter do all the work. Values for a single-pole filter can be obtained from the NE602 receiver Frontend.
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