Time coincidence counting from a pulse generator
Objectives:

– to study work of a pulse splitter
– to work with signals from a pulse generator
– to arrange the setup for time coincidence counting from a pulse generator
– to determine the maximum delay for the second signal from the pulse generator
at which the coincidence scheme still triggers
– to determine the time of minimum signal overlapping at which
the coincidence scheme still triggers

Instrumentation:

– CAMAC crate
– Pulse generator
– Pulse splitter
– Delay module
– Coincidence scheme
– Slave crate controller
– Pulse counter
– Digital oscilloscope
– Connecting wires
Feed 2 identical signals from the pulse generator to the oscilloscope by the use of the pulse splitter. A pulse splitter is a device that splits a signal into two or more identical signals. We need to use such the device if we have to observe the same signal at oscilloscope screen and feed it into another CAMAC block, for example to a coincidence scheme.

So firstly connect 2 outputs of the pulse generator with 2 inputs of the pulse splitter. Then connect 2 outputs of the pulse splitter with two channels of the digital oscilloscope. As result you will see 2 identical signals from the pulse generator, which have the same amplitude and duration.
Feed 2 identical signals from the pulse generator to the oscilloscope by the use of the pulse splitter. A pulse splitter is a device that splits a signal into two or more identical signals. We need to use such the device if we have to observe the same signal at oscilloscope screen and feed it into another CAMAC block, for example to a coincidence scheme.

So firstly connect 2 outputs of the pulse generator with 2 inputs of the pulse splitter. Then connect 2 outputs of the pulse splitter with two channels of the digital oscilloscope. As result you will see 2 identical signals from the pulse generator, which have the same amplitude and duration.
Now let’s feed one of the signals into the input of the delay module. For this take off one cable that connects the pulse generator and the pulse splitter. Then connect free output of the pulse generator with the input of the delay module. Then feed the signal from the delay module to the input of the pulse splitter (you should use the input of the splitter section where we have already used one output before). As a result you will see the same picture – 2 identical signals on the oscilloscope screen.

Notice that in real life the second signal (that was fed to the delay module) will be delayed also by the delay module and by the additional cables. In that case you should see on the oscilloscope screen that the second signal is delayed relative to the first signal. But in our case we will consider that such the delay is compensated by more long cables of the first signal.
Let’s work with the delay module. Each of the buttons on the delay block delays the signal for denoted number of nanoseconds. You can press several buttons simultaneously to choose the necessary delay.

Delay one signal so that it doesn’t overlap with another one. Later we will study the work of the coincidence system, which triggers only when 2 signals overlap.
From the pulse splitter feed both signals to the coincidence scheme. Feed a signal from the output of coincidence scheme to the input of the pulse counter.
From the pulse splitter feed both signals to the coincidence scheme. Feed a signal from the output of coincidence scheme to the input of the pulse counter.
Switch on the pulse counter by releasing the button “Z” on the slave crate controller. As you see on the oscilloscope screen we have 2 identical signals. That is why the coincidence scheme triggers. And we can be sure in it because the pulse counter counts signals from it.

If we delay the second signal until it won’t overlap with the first one we will see that the pulse counter stops counting. So in our setup the pulse counter is the indicator of the coincidence scheme triggering.

Determine experimentally the maximum signal delay at which the coincidence scheme triggers.
Maximum signal delay at which the coincidence scheme triggers: ns
Switch on the pulse counter by releasing the button “Z” on the slave crate controller. Determine experimentally the minimum time of signals overlapping at which the coincidence scheme triggers.

To enlarge a CAMAC block or elements of the oscilloscope, just click on them twice.
Minimum time of signals overlapping at which the coincidence scheme triggers: ns
Nice work! Now we see that for our module of the coincidence scheme the maximum signal delay at which the coincidence scheme Now we see that for our module of the coincidence scheme the maximum signal delay at which the coincidence scheme triggers is 35 nanoseconds, and the minimum time of signals overlapping at which the coincidence scheme triggers is 5 nanoseconds. So we have determined important parameters of our coincidence scheme which we should take into account before new experiment planning.