[ICOM] "Roofing Filter" for 746

[Dave Meitzen]

My guess is it is some what more complex. I think about impedance matching
the input and the output. I think the INRAD may need an amplifier to make up
for insertion loss. All that said this is an interesting project and I would
love to hear how it works out because I also have a 746Pro.
Best Regards
Dave aa9tt 

-----Original Message-----
From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] On
Behalf Of Mike
Sent: Sunday, August 26, 2007 3:20 PM
To: icom at mailman.qth.net
Subject: [ICOM] "Roofing Filter" for 746

Hello,

Has anyone installed a "roofing filter" in the 746's 69.0115 MHz IF?

Tempted to install a "roofing filter" in the 746's 69.0115 MHz IF using the
INRAD Roofing Filter for the ICOM 765/775, but would like to find any info.
on others that have done same or similar and what were their experiences.

My thinking on "how to do this" is to break the junctions of C252 to
L251 and C253 to L252, and insert the INRAD Roofing Filter between
L251 and L252 at the junctions of where C252 and C253 had been.  FL1231B now
is replaced by the INRAD.  FL1231A and its associated amplifier, are still
functioning offering some wide (16
KHz) filtering prior to the 5 KHz INRAD.

         73,
         Mike, K4GMH
----
Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net Icom Users
Net: Sundays, 1700Z, 14.316 MHz Icom FAQ: http://www.qsl.net/icom/