CF8000 Octal Constant-Fraction Discriminator

• Good time resolution with a wide range of pulse amplitudes
• Internal delay - no cable necessary
• ECL outputs
• Energy Outputs
• Automatic walk adjustment
• Multiplicity and OR logic outputs
• Analog sum output
• Inhibit input

The flexible ORTEC CF8000 Octal Constant-Fraction Discriminator has the performance and convenience features necessary for ease of use in even the most demanding timing or coincidence experiments with multiple detectors. It contains eight constant-fraction discriminators in a single-width NIM module. The constant-fraction technique provides optimum time resolution over a wide range of pulse amplitudes.

Exclusive features of the CF8000 discriminator include internal shaping delay, automatic walk adjustmetn, an analog summation output, and built-in logic functions to minimize external logic requirements.

The input signals can range from 0 to -5 V. Each input has a separate threshold adjustment (with front-panel monitor), which may range from -10 mV to -1 V.

For each channel, there are three Fast-NIM logic outputs - one "A" and two "B" outputs. All outputs have adjustable widths. There is a single-width adjustment for all eight "A" outputs, and another width adjustment for all 16 "B" outputs. There are also eight rear-panel ECL outputs that have the same width as the "B" outputs. LEMO connectors are used for maximum packing density.

Each channel has a rear-panel "E" output that buffers the input signal.

External delay cables are not necessary on the CF8000 discriminator. Each channel has an internal shaping-delay circuit that can be set for 2, 4, 6, 8, or 10 ns. Optional delay line plug-ins are available for changing the shaping delay ranges to 5, 30, or 50 ns. For all delay plug-ins, there are five possible delay settings. (See Accessories section.)

The automatic-walk adjustment of the CF8000 instrument simplifies set-up and reduces the effects of ground-loops on the incoming signal.

Other front-panel connections include: (1) an analog sum output (S), which provides an attenuated summation of all inputs; (2) a multiplicity output (M), which provides a voltage proportional to the number of valid "B" outputs; (3) an OR logic output that provides a logic output for every active "B" output; and (4) an inhibit input (INH), which disables all "B" outputs.

The constant-fraction ratio is factory set at 0.4.

ORDERING INFORMATION

Order eight delay options to populate all 8 discriminator channels.