C894

The Mod. C894 is a 16 Channel Leading Edge Discriminator housed in a single width CAMAC module. The module accepts 16 negative inputs (positive on request) and produces 16 differential ECL outputs with a fan-out of two on two front panel header connectors. The pulse forming stage of the discriminator produces an output pulse whose width is adjustable in a range from 5 ns to 40 ns.
Each channel can work both in Updating and Non-Updating mode according to on-board jumpers position.
The discriminator thresholds are individually settable in a range from -1 mV to -255 mV (1 mV step), via CAMAC through an 8-bit DAC. The minimum detectable signal is -5 mV.
VETO and TEST inputs are available on the back panel. A Current Sum output generates a current proportional to the input multiplicity, i. e. to the number of channels over threshold, at a rate of -1.0 mA per hit ±20%.
A “MAJORITY” output on a back panel connector provides a NIM signal if the number of input channels over threshold exceeds the MAJORITY programmed value. Several C894 boards can be connected in a daisy chain via the Current Sum output: in this case, by switching the Majority logic to “External”, it’s possible to obtain a Majority signal when the number of over threshold channels in the daisy chained modules exceeds a global Majority level.
An “OR” output on a front panel connector provides a global OR of the output channels.