The TR-1 uses Texas Instruments' NPN transistors, hand-picked in sets of four. A 22.5 volt battery provides power, since the only way to get adequate radio frequency performance out of early transistors was to run them close to their collector-to-emitter breakdown voltage. The current drain from this battery is only 4 mA, allowing 20 to 30 hours of operation, in comparison to only several hours for the portable receivers based on vacuum tubes. The Regency TR-1 is patented by Richard C. Koch, , former Project Engineer of I.D.E.A.