Butt sets and a power supply should work for you. We used to use our toners in series with or test sets between IDFs a lot (before cell phones) as RICK suggests. That wont be enough juice over your 30 miles though.

Looking on the bright side, you ARE working with 19awg wire. And, 30 miles of 19awg has the same resistance as about 9.5 miles of 24awg (now it doesn't sound all that far [Linked Image from sundance-communications.com] ).

I think I would try talk battery from an old 1A2 power supply. I haven't used one for years. There used to be several manufacturers that made them. Elgin is the brand we used the most.

Good Luck!

Marty Beutler
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