ORIGINAL MESSAGE: (may be snipped)
On 5/12/2014 9:33 AM, Jerome Sodus wrote:
Hello Bill,
The term "roofing-filter" made sense back in the 1980's when I designed
roofing-filters at 70 MHz.
Bandwidths would be in tens of KHz.
The purpose then was to protect downstream circuitry by rejecting very
strong out-of-band signals that could cause overload; selectivity was not
the purpose.
Selectivity was done further downstream.
So the term has become corrupted over the years.
73 Jerry KM3K
REPLY:
I still don't get it. What does the word "roof" have to do with
bandpass? That's where the confusion comes from.
73, Bill W6WRT
[email protected]
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