On Nov 24, 8:35*pm, Clark wrote:

I just put a 327 in my aircraft - thanks for posting this 'cause it gave me
an excuse to re-read the manual to verify that "On" is Mode A. I'll check
it tomorrow for some visual feedback that Mode A is active vice Mode C.

If you could post your findings, this will be helpful for me for the
next time I fly in that plane, even as a passenger. I hope that I
don't have to use this new found knowledge on a transponder that was
"just fixed" but one just never knows.

For something as benign as a transponder, when it hiccups, it can add
workload to "flying the plane" :-)