Ron,

I think we may have discussed this earlier, but I don't think there is 
any way to do this.   I think your only other options are to get other 
pf keys, either  with a home brew box, a mic with extra pf keys, or a 
mic with up/down buttons that can be reassigned as pf keys.

As far as I know, the TX tune function you are using has no front panel 
  button, it can only be done with a pf key.

73, Steve KW3A

On 11/16/2014 10:04 AM, Dr. Ronald E. Milliman]\\` wrote:
> Steve, do you know if you have your PF1 key to the left of the power button,
> set the way you have yours, can you also have this same key set to activate
> the tune function? Right now, I have that key programmed so that when I
> depress it, the 590 goes into tune function, decreasing the power down to
> around 10 watts and allowing me to tune my automatic antenna tuner for
> minimum SWR. I use it all of the time for this purpose. Do you know if I can
> keep it programmed to use this way, but then, also program it to work the
> way you use yours when in transmit??
>
> Ron, K8HSY
>
>
>