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Philco 91-221 antena transformer primary
#9

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


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RE: Philco 91-221 antena transformer primary - by Joeztech - 03-23-2014, 03:54 PM



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