  Standard optical pump-probe methods analyze a system's temporal response to a
laser pulse within sub-femtoseconds to several nanoseconds, constrained by the
optical delay line's length. While resistance is a sensitive detector in
various fields, its measurements are typically slow (>microseconds) due to
stabilization requirements. We suggest here a time-resolved pump-probe
technique which combines an optical pump pulse and a rectangular electrical
probe pulse through the sample, measuring transmission in a 50 Ohm matched
circuit with a digital oscilloscope. This allows electrically-driven delays
from nanoseconds to seconds. Demonstrations include studying heat-induced
changes in a thin amorphous VO$_x$ film and carrier relaxation in a CdS
photoresistor, showcasing potential applications in heat transfer, biochemical
reactions, and gradual electronic transformations.
