[Elecraft] K3 lock out via Inhibit

[Igor Sokolov]

Yet again I need to organize lock out for a pair of K3s. Therefore  couple 
of questions for those who knows how to do it.

1)The manual says one need 2.2 to 10k pull up resistor on pin 7 of the ACC 
connector from 5V source. There is no 5V source in ACC connector (BTW 
Elecraft could easily provide one either on pin 12 or pin 5. Both of them 
are now used for GROUND). The easy answer to the problem is to use 12V  out 
RCA socket on the back panel. Is it necessary to step down that 12V to 5V or 
it is safe enough to connect say 20K pull up resistor from 12V to pin 7 ?
2) Is it OK to use Keyout-Lp from pin 10 of one radio to Inh pin 7 of the 
other radio and vise versa. What I am concerned about is what happen if on 
one of the rigs someone unintentionally switch the setting of pin 7  from 
Inh to K3 ON?

73, Igor UA9CDC