LED circuit request/question

Hi folks. A friend asked me to help with a project; I’ve forgotten my basic EE from school and could use a hand. He wants a wearable board that has two LEDs blinking in their own cadence. My thought went right to the VHS Blinkie Badge, but he doesn’t want them to blink alternating. Is that an easy change to the badge to make one blink faster than the other? He wants it to ideally run off one or two coin cells so I don’t think a microcontroller is likely to work?

A microcontroller could work, but would be more work than it’s worth to reduce power draw.

On the VHS blinky badge, replace one of the 47k resistors with, I dunno a 100k potentiometer, then you can tune it however you like. It’s called an astable multivibrator if you want to look up a schematic.

Thanks Jarrett, I’ll do some reading. I wasn’t sure that would change just one side’s speed.