Thanks for the replies. I'll complete this thread by explaining what was
necessary to get the audio from the 496 into the 403mc. I added a 1/8 inch
stereo jack to the panel to plug the Garmin-provided 1/8 inch audio patch
cable into. At first I soldered a wire between pin 18 of the intercom cable
and the center conductor of the 1/8 inch audio jack. In that configuration
I had to pull the 1/8 inch plug partially out to get the bitchin Betty
warnings into the intercom. After moving the audio wire from the middle to
the end conductor on the jack, bitchin Betty worked as expected with the
plug pushed fully into the jack. The xm audio signal worked in both
positions but of course was sans stereo because of the mono intercom.

The warnings from the 496 in a pleasant female voice add an interesting
level of technical sophistication to the cockpit environment. So far I've
been told '500 ft' on final approach, heard 'Caution, terrain' when flying
past high terrain, 'Warning, terrain, pull up!' when flying toward high
terrain, 'External power lost' when pulling the power plug, and 'Sink rate,
pull up!' when flying a steep final approach .
--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

It is not work that kills men; it is worry. Worry is rust upon the blade.
"mikem" wrote in message
ups.com...
On Aug 19, 6:37 pm, "Mike Noel" wrote:
I've just upgraded to a garmin 496 from a 296 and want to hook up the
audio
output to the intercom. I haven't had a chance to look at the back of
the
intercom. Can anyone tell me what kind of auxiliary connection the 403mc
uses? I would like to make up a patch cable before I visit the hangar
next
weekend. Thanks.

--
Best Regards,
Mike

Mike,
Search old "owning" posts. I wrote this: http://tinyurl.com/ypp4rs



MikeM