The Model 620L is a new, low cost, 8-fold discriminator combining the most useful operating features of standard, general-purpose discriminators with the high packaging density, economy, and improved input characteristics afforded by a hybrid circuit input stage.
OPERATIONAL FEATURES INCLUDE:
* Low variable input threshold of -30 mV provides compatibility with lower gain hodoscope counters or with signals which may have been degraded by long cable delays.
* Excellent threshold stability of <0.2%/' C preserves threshold of value over varying operating environment.
* No multiple-pulsing. One, and only one, output is produced regardless of input duration or amplitude.
* High fan-out of three NIM level voltage outputs.
* Variable output width from 5 - 20 ns is independent of input duration, amplitude, and rate; no need for width cables.
* Low time slewing provides accurate timing signals regardless of the distribution of input amplitudes.
* Fixed recovery time of 4 ns after the trailing edge of output pulse.
* Short input-output delay minimizes need for long compensating delay cables and provides prompt outputs.
* Low cost without sacrifice of performance or quality.
SPECIFICATIONS
NIM Model 620L
8-CHANNEL DISCRIMINATOR
INPUT CHARACTERISTICS:
Impedance: 50 Ohm +/-1%; reflections <+/-2% for 2 ns risetime.
Coupling: Direct; offset +/-2 mV.
Protection: +/-5 amperes for 0.5 us.
Threshold Stability: 0.2%/' C.
Threshold: -30 mV to -1 V; front-panel control common to all channels.
Threshold Test Point: DC voltage equal to 10X threshold setting (e.g., at 500 mV on test point
actual threshold is 50 mV).
Rate: CW: >100 MHz.
Double-Pulse Resolution: 8 ns.
Slewing: 1 ns, 1 1 0% threshold to 1 OX overdrive.
OUTPUT CHARACTERISTICS:
Output duration variable from 5 -20 ns; 3 NIM level voltage outputs; rise
and fall times <2.5 ns.
GENERAL:
Propagation Delay: 7.5 ns nominal.
Bin Gate: A slow bin gate inhibits unit when line is clamped to ground;
enable-disable switch mounted on rear panel.
Packaging: 8 channels in AEC single-width module; Lemo coaxial connectors.
Power Requirements: +6 V at 180 mA; -6 V at 650 mA.
Optional, at slight additional cost: internal power supply operating from
120 VAC to eliminate +/-6 V requirement.