"Ron Natalie" wrote...

Squawk 7700 briefly (15 seconds?) to get the attention of ATC, and to
give
some notice of your intention to exercise your PIC emergency authority to
"bend"
the regulations.

Not necessary. If squawking anything is working, 7600 will get their
attention just
find. You don't need to give them any such notification.

I don't know the current state of the art of ATC radars. However, the 7700/7600
switch was a part of the Navy Instrument Flight Manual as late as 1994. The
rationale was that not all ATC radars had the same level of alerting for 7600
squawks as 7700, and/or that the alert might be manually disabled.

If all ATC radars now have the same level of alert for a 7600 squawk, then 7600
only makes sense.