[Elecraft] re ON-OFF on K3

[Eric Scace K3NA]

   The need to manually press the power button to turn on the radio is a 
problem in remote-controlled stations.  If power fails, one must visit 
the site to power up the radios.

That said, there are often many transients when power is first restored.

An ideal solution would have these attributes:
   -- if the radio was powered up when the +13 Vdc supply voltage 
disappeared, then...
   -- when +13 Vdc reappears, wait 3 seconds, and then power-up the radio.

73,
   -- Eric K3NA