[Elecraft] [K3] Roofing filters are misunderstood

[Bill Turner]

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
dezrat at outlook.com