Make an analog pulse generator
If you're up to it, I'd recommend looking into something called a monostable vibrator (it's really just a one shot pulser, each time you trigger it, it generates a single pulse - you can chose how long the pulse is). Monostables can be built using 555 timer chips and there's about a billion 555 example circuits on the internet for doing just about everything, ideally find something by Forrest Mims, bit of a 555 guru.