[K3] 250hz 8 pole filter suddenly causes loss of signal strength

[Art Suberbielle]

I spend 100% of my time operating CW and like narrow filter BW. Usually operate at 350 to 300hz BW, and often tighter, utilizing my 250hz filter. Today as I cranked down the Band Width, I discovered a 24 db drop in signal strength when the 250hz filter switched in. Went back and verified all the Config settings were correct. Filter is ON, Gn 4 db, Filter Frequency Zero (as per manual with 8 pole filters).

Can the filter go South for no apparent reason? Or am I missing something. When I switch the filter in line, I basically lose a signal, dropping 4 S units.

The only other thing I've done is to align the Reference Oscillator with WWV after connecting a P3.

Your input will be appreciated.

73,

Art KZ5D





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[k5oai]

On 8/22/2010 8:49 PM, [hidden email] wrote:
>
> I spend 100% of my time operating CW and like narrow filter BW. Usually operate at 350 to 300hz BW, and often tighter, utilizing my 250hz filter. Today as I cranked down the Band Width, I discovered a 24 db drop in signal strength when the 250hz filter switched in. Went back and verified all the Config settings were correct. Filter is ON, Gn 4 db, Filter Frequency Zero (as per manual with 8 pole filters).
>
> Can the filter go South for no apparent reason? Or am I missing something. When I switch the filter in line, I basically lose a signal, dropping 4 S units.
>
> The only other thing I've done is to align the Reference Oscillator with WWV after connecting a P3.
>
> Your input will be appreciated.
>
page 46 owners manual
Filter Loss Compensation


--
GB & 73
K5OAI
Sam Morgan
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