With 250 psec width and delay resolution and <200 psec internal jitter, 4- or 8-channel Model 577 enables precise timing up to 1,000 sec. Each output is individually configurable with its own trigger, gate, delay, and width settings. Optical and electrical outputs and inputs (or combination thereof) are optionally available, and LED output stage can be configured for 2, 4, or 8 outputs at 820 or 1,300 nm. Other features include pulse picking and selectable external clocks.