A vacuum gage is very cheap. And easy to use. You can buy a kit at any parts store with the common fittings included as well as simple operating instructions.
A scope not so much… and you gotta understand how to use it. It isn;t something you can just figure out when you get it unless you already understand how CRTs basically work (although the signals are now converted into digital simulations for display on flat screens), sweep rates, and a number of other basic settings related to the size of the pulse etc. In short, you’d need some basic electronics training first.
I’d explain why I call the digital displays “simulations”, but that would get a bit deeper.
Oh… what the heck. With a Cathode Ray Tube, the electrons stream from the gun is bent directly by putting the signal between deflection plates, totally analog. With digital displays, it’s all turned into I’s and O’s, totally binary, and then converted to a representation of the original signal. So I call it a “simulation”. Technically I shouldn’t, but I’m biased against digital. I’m old. I’m analog. I like to fill in the whole signal.
Digital displays are really fine. It’s just an old bias of mine.
Oh, regarding that timing light, does it have a 6VDC setting? The light needs its correct operating voltage to enable the induced pulse to flash the light. Understand too that the light only flashes when it senses the pulse from the ignition wire.