I am receiveing answers off forum which indicate YES and NO.

Does ANYONE have an AT-250 which they can hook up WITHOUT any
d.i.n.cable to verify if it will operate as a tuner- r.f. sensing?

The manual (such as it is) is very much lacking in this area.

I have used it with the 430, and with other rigs WITH the d.i.n. cable.
It works fine.

My question is: Will the AT-250 operate with only a coax connection
and d.c. connection and tune from the signal it gets from the
transmitter?

Thanks again.
k8vf