From tigwiki

Circuit diagram for the dead time calibration setup.

This section describes the calibration of the dead time for a setup using the ZDS going into five different dual-gate generators with delayed outputs, which generate five different dead time settings. The signals are send to five different data inputs of the MCS (at the moment, data input channels 24 and 27-31 are not occupied).

In order to calibrate the dead time, a random pulse generator and a high precision clock is used. Only two high-precision pulser are available in the electronic shack at the moment, which operate in the kHz region. Therefore, the signals for JORWAY clock and MCS clock have to be taken from the same unit. The JORWAY clock input requires positive signals, the MCS clock negative signals, so that a sequence of TTL to NIM unit and discriminator is used to generate pulses which can be read by the MCS external clock input (channel 1).

The idea of the calibration is to feed the signals of the precision and random pulser into a logic unit with an OR gate, before they are divided and fed into the dual-gate generators. The random pulse signal is fed through the ZDS electronics. Note that the preamplifier Phillips 776 shapes the signal in a funny way, as it expects negative signals from a photomultiplier tube. The precision signal is periodically switched on and off, which is achieved by sending it through a logic unit with a VETO signal, which is connected to the beam ticker output from the JORWAY cycle.

A typical JORWAY cycle program may contain cycles alternating with beam on and beam off, corresponding to the precision pulser being switched off and on. Note that the prescale factor has to be adjusted such, that the number of bins does not exceed approximately 250, as the counting is unreliable above that value at the moment.