In the long run, I think that you'll need to come up with a script to do it. Or do the Echolink thing.
Since you mention it, I would also wonder about the advisability of running a transmitter that has relatively little heat sink for the 30-40 minutes involved.
In my case it's a Mastr II continous duty station that will make 100 watts until the cows come home and not complain.
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Bob Poff
Loganville, Pa