[amsat-bb] Re: mode J filter / Comet CF416c

Andrew Glasbrenner glasbrenner at mindspring.com
Fri Dec 28 10:18:07 PST 2007

-----Original Message-----
>From: Ken Shutt <kgshutt at cox.net>
>I would recommend putting the preamp as close to the antenna as possible. 
>The diplexer should go between the radio and pre amp.  If you are planning 
>to feed dc to the preamp on the coax, you need to make sure the diplexer 
>will pass the dc to the preamp.
>73 de Ken W5KQ

Hi Ken,
I think Kyle is wanting to use the diplexer as a high-pass filter in front of the preamp to prevent the 2m uplink signal from overloading the preamp, as explained at http://www.amsat.org/amsat-new/articles/Mode-J/ .

73, Drew KO4MA

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