Quite often it is necessary to change parameters of many pulse at the same time. Doing it “by hand”, one by one, would not be a nice solution. Let the computer do the job! All you need is to describe the relations between these pulses. And you can do it using the COUPLING menu.
It works in the following way (let us start with the amplitudes, the timing is analogous). First you have to choose a reference pulse, we call it a “master”. Next you make another pulse to be this master’s “slave” and define the function for its amplitude:
Aslave = Amaster * factor + offset
You can create many “masters” and each of them may have many “slaves”. There is no limit on their number nor on their placement (different waveforms, even those not seen on the screen).
Let us make the pulse number 1 in the A-waveform a master-amplitude. If this pulse is not selected, click on it in the superposition pane and make sure that the red frame surrounds the “A” letter. Choose COUPLING->SET MASTER AMPLITUDE… and the dialog will be displayed asking you to type a name for this master pulse.
Type a name (like “the first master”, as in the example) and click OK.
Now go to the pulse number 4 and choose COUPLE TO… from the same menu (or press cmd-K). You will see another dialog. It has a pop-up menu to choose the master and two edit fields to write the equation describing the relation between this slave pulse and its master:
If you type the factor “-1” as in this example, the pulse number 5 will be a counter pulse of the pulse number 1. Click OK and try to change the amplitude of the master or the slave pulse to see how they follow each other.
Please notice that the horizontal lines in the coupled pulses have changed their color to red (master) or blue (slaves). In practice you do not need to care which pulse is a master and which is a slave (with one exception, see below). If you change an amplitude of a slave, it informs its master about this. The master calculates its own new amplitude and broadcasts it to all its slaves, which, in turn, change their amplitudes according to the programmed equation.
The only time you need to know which are the masters is when you want to delete some pulses or waveforms. If such selection contains a master, the computer will protest. The solution to your problem is quite simple - you just tell another slave to become a master. Then the old master will become a slave and you will be able to do whatever you like with it. The command is called PROMOTE TO MASTER.
It is, of course, a lot of job to make slave pulses one by one. Try the following sequence of commands: zoom out once, select all, duplicate, copy, change to B-waveform, paste, invert selection. You should get something like this:
Try to change an amplitude of the coupled pulses and observe how they behave. You see that the copy/paste/duplicate commands create new slaves and the “invert” command changes the sign of the multiplication factor in the equation. So, you can create a master first and make all the slaves just by duplicating, copying, inverting, etc.
You may change the name of a master, jump to the master, clear one coupling chain or all couplings.