I have been receiving quite a bit of mail concerning broadcast rejection
and the necessity of needing additional filtering for BC stations. Today I
took my own pre-amp and did the following measurements on it:
freq gain min gain max
1840 unity (0db) 23 db
1540 -24db -24db
1000 -46db -46db
.500 > -60db > -60db
This clearly shows that the pre-amp with tuned input and tuned output
stages reduces BC stations by a significant amount, depending on the
stations freq. Using the pre-amp at low gain settings can enhance
rejection, or even improve overload by turning off the receiver's internal
pre-amp, and making up the gain with the external amp which add two tuned
stages of rejection. Thanks for listening and any comments appreciated.
de gary, kd9sv
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