An all‐electronic generator is described which provides a voltage which varies linearly with time between adjustable positive and negative limits. Such a generator lends itself well to the automatic recording of current‐dependent phenomena. Linear variation is obtained on both the rising and falling half‐cycles, so that complete reversal of slow processes may be assured. The maximum current provided in either direction is 3 amps. The limit is determined by the number of output tubes connected in parallel. Cycling periods up to 1 min in length are provided.