Thanks Stan
1. The duration of the open "window" in the secondary circuit should be the same for press and release. It would be as short as possible and still provide reliable actuation of the target device. I'm guessing about 0.1 to 0.2, seconds but if I'm wrong it would be nice to have a provision to lengthen it.
2. No. If the foot pedal is pressed to any depth or velocity, the primary circuit opens. This should trigger an open window of brief but fixed duration in the secondary circuit. And when continuity in the primary circuit is restored (i.e., spring-loaded foot pedal is released), that should trigger ANOTHER open window of brief, fixed duration. It's important that the system always produce two complete cycles, so as to return to its original state. Both of the open periods ("windows") in the secondary circuit are the same length. If the foot pedal is held down for a long time, it allows the user to delay the second half of the cycle. Because the trigger event for the second half is restoration of continuity in the primary circuit, and that will happen when the user releases the pedal.
Another example, and something to consider... if you press the pedal only partway down and then release it immediately, the secondary circuit should go from default closed to a brief open and back to closed, and then once again a brief open and back to closed. If my guess is correct and the duration of the open window is indeed 0.2 seconds, then the minimum "resolution" of the whole system would be about a half-second. In other words, if you press and release the primary pedal multiple times within a half-second, subsequent presses would be ignored because the delay loop is running and the system always needs to complete both cycles to restore itself to the default state.
One concern I have with the module Leo recommended, is that in my case, the footswitch in the primary circuit is normally closed. When you press it changes to open. However, it seems like that module (and others like it) expects a default open circuit, and a trigger event of closing the primary circuit to start the timer function.
The key piece here (and the reason I'm afraid I'll need something like an arduino to control the relay), is that RELEASING the foot pedal in the primary circuit is also a trigger event. There are millions of switches and electrical devices that trigger on press. But the release (and restoration of continuity in the primary circuit) somehow has to be "sensed" which completes a logical loop that executes the remaining events. That sounds like computer logic to me.
Really appreciate all the help!!
