[aprssig] Variable Resistor on KPC3+?

[Michael J. Wolthuis]

I was recently assigned to get a Peet Brother's weather station connected to
a KPC3+ on the DB25 port back into working order.  When we checked the DB25
cable to the RJ11 on the Peet Brother's it has something I have not seen
before and I was hoping someone could enlighten me what it is doing.

The Peet Brother's is connected on pins 2,3,7 of the DB25 and then there is
a 100K Variable Resistor connected to pins 1,13, 15.  I am wondering if this
VR is necessary or what it is even doing.  I do not run it on my Peet
Brother's station.

Thanks,
Mike
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