Question about pulse

WVR - I've run across schematics for home-brew throttles and such, including pulse control, while web-surfing. Try doing a web search for sites with the words model train throttle schematic and the like. They are out there, I just forgot where!
 
I have the construction manual for building your own "TAT IV" throttle. I built mine in 1974 and it's a peach. can handle up to 2.5 Amps and is easy to build too. The transformer is not contained in the throttle box. I've run "N", "HO" and "G" gauge locos from it.

Specs are:-
Variable pulse frequency.
Variable pulse amplitude.
Variable loco "start" voltage preset.
Variable loco "max speed" voltage.
Start pulse (diminishes as throttle voltage reaches start pulse amplitude)
Brake switch from light to "emergency".
Includes a full size circuit board picture.
Adaptable for adding a walk around (tethered) throttle.

This puppy beats all the rest into a cocked hat.
Just ask and I'll send details off-forum.
Is this what you're looking for?

Errol