Another viewpoint: I have both filters (500 and 250) in my Corsair
II, and found that I never used the 250. Too narrow for comfortable
tuning, and if I couldn't isolate a signal in the 500 hz bandpass it
wasn't worth the aggravation anyway.
This is sort of my experience too. I do use the model 221 six pole 250
Hz filter in the 9 MHz IF a lot. However the model 282 in the 6.3 MHz
IF never gets used . Using the 250 Hz 8 pole filter "interferes" with,
or detracts from, my own ability to discriminate between
noise and CW signals. I found I was also not using the 250 Hz filter in
a FT-1000 this weekend for the same reason. It seems like the main
purpose of a 250 Hz 8 pole filter is to use it to demonstrate that you
don't really need a filter narrower than 500 Hz. This is for human
copied CW, there may be practical application of the 250 Hz filter for
other modes.
DE N6KB
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