Stepping down voltage 120 VAC to either 110 VAC or 117 VAC
First, in general your radios should work OK at 120VAC.  Mains voltage has always varied, which is why the power company could get away with bumping it up over the years.

Second, you can install a filament transformer with the correct secondary current rating, set up to buck the AC.  It should be fairly small.  While you're observing all due safety precautions, also check that you're bucking the AC voltage, and not boosting it.  A 6V filament transformer should get you from 120V to 114V, which ought to be in the neighborhood you want.







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