[Elecraft] Deactivate the sub receiver

[Tim Gennett]

There's a possibility my K3 may be used in a multi op setting where many of
the users would not be familiar with the K3.   I'm trying to think of ways
to simplify the operation so that those not familiar with the controls
don't accidentally put it into some dysfunctional configuration.

Specifically, is there a way to disable the sub receiver?  I looked for
something in the Config menu but did not find anything relevant.

I suppose I could remove it but that seems drastic.

Any other simplification suggestions?

Tim K9WX