[Drake] TR7 filter

Sat, 28 Feb 2004 21:29:31 -0600

Hi Henry,

I don't know if it is a known thing but my 300 Hz filter did the same thing
many years ago. I have had my TR7 since 1978 and in 1984 it suddenly
developed significant loss. It was one of the Network Sciences filters. My
500 Hz filter is the original and still working fine.

73,

John K5QX

----- Original Message ----- 
From: "HENRY PFIZENMAYER" <[email protected]>
To: <[email protected]>
Sent: Saturday, February 28, 2004 8:07 PM
Subject: [Drake] TR7 filter

> TR7 Gurus ....
>
> I notice that my  300 cycle filter position seems to be getting more lossy
> with time
> ... Is this a known thing with the 300 cycle filter over a long period
????
> It is 4 to 5 db more lossy than the 500/1.8/2.3 khz filters now.
>
> Guess it is not inconceivable (maybe even more likely) that one or more of
> the MPN3404 switching Pin diodes associated with the 300 cycle filter is
not
> up to snuff .. Anyone seen this before I rip this thing open again and
pull
> the filter board to check ?
>
> I have a R7 receiver and the 300 cycle filter in that receiver seems to be
> the same as the 4.0, 2.3 and 1.8 khz filters  (The 500 cycle filter in my
R7
> is about 3 to 4 db less lossy than any of the other filters) .
>
>
>
>
>
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