03-23-2014, 03:54 PM
In answer to your question about why a resistor is bridged across the coil or primary of the RF input transformer, this is usually done to broaden the bandwidth of a coil/transformer assembly. Sometimes coils or transformers have high enough Q that they tend to tune rather sharply to a small range of frequencies. A resistor can be bridged across the coil or transformer winding and the result it a much broader bandwidth. On an RF input, this helps keep the signal sensitivity from low to high frequencies pretty nearly equal as the radio is tuned across the dial.
Joe
Joe