Posted for <bjburr@mwheli.com>:

 Alan,
 In speaking with Jordan Bach at D2A 2 days ago he has not been able to
 get the SL40 to interface with the Chelton for frequency selection.  The
 SL30 works just fine.  So, my assumption is that it doesn't work.
 Perhaps there is some incorrect connection but I think Jordan is the
 expert in these interfaces.
 
 Bryan
 N132BB
 
[ SL-40 tuning didn't work due to slight differences from
the SL-30 in the serial interface on 5.0A, Fixed in 5.0B late 2004
and FAA blessed early 2005 -Rob ]