The Model 577 Digital Delay/Pulse Generator from Berkeley Nucleonics includes several features to optimize measurement accuracy. The Model 577 offers 250-ps width and delay resolution, while keeping internal jitter to less than 200 ps. The Model 577, which is outfitted with four or eight channels, performs gating, triggering, delaying, clocking, and synchronization with timing precision that is sufficient for almost any application.
Each of the Model 577’s outputs can be individually configured with its own trigger, gate, delay, and width settings, giving you maximum control over your measurements. Inputs and outputs can be all electrical, all optical, or a combination of both. I particularly appreciate the LED output stage, which is available at the front panel. This will simplify measurements in noisy environments or for communications applications. This modular option can be configured for two, four, or eight outputs at 820 nm or 1300 nm.
I recommend learning more about this model. You can read more here: http://www.edn.com/electronics-products/other/4440292/Delay-pulse-generator-delivers-picosecond-resolution.