A technique for producing multiple protein blots from a single gel, including entering the number ‘n’ membranes to be blotted into microprocessor memory, determining calibration constants for a gel batch, inputting calibration constants into microprocessor memory, and calculating ‘n’ voltage/time profiles for simultaneous blotting. A gel layer from the gel batch is treated with a protein sample, ‘n’ membranes are placed onto the gel layer to yield a gel pack, and the gel pack is placed between an electrode plate maintained at a fixed first voltage and an array of ‘n’ spaced generally parallel electrodes. The voltage to each respective ‘n’ spaced generally parallel electrodes is varied over time according to a respective ‘n’ voltage/time profile to transfer proteins to each respective ‘n’ membranes to yield blotted membranes to yield ‘n’ respective blotted membranes.