On Thu, Jun 30, 2011 at 6:35 PM, Doug Philips <douglas.philips@xxxxxxxxx> wrote: > I doubt that is why many non-military keys have a grounding > bar/switch, but it might explain why some do... There are a few situations when I'd want to send a continuous tone (antenna tuning, amplifier tests, tracking down problems), but I have to admit 'sending a distress signal from my burning plane while I parachute to safety" isn't one that's come up so far.