Process Analysis: allow source to send items depending on another source

[martin_madaj]

For example, I got two sources: the first source would send items with predefined output rate, the second one would send items depending on whether the first source sent the item or not. In other words, I want the second source to send the workpiece (item) only when the order arrives from the first source.

I now I can use the Merge function and force the order to wait for the workpiece (item) but I don't want to use constant (scheduled) output rate with no relation to the occurence of the order.