Testing the gear teeth sensor assembly in anger

Simple enough task - connect up a couple of pull-up resistors, a power supply and a scope and see if it actually works. Worst case it may provide wildly asymmetrical waveforms (I want a duty cycle of 40-60% or so from each, so they overlap) or not even switch properly.

Naturally, the biggest challenge was actually finding some good old fashioned through-hole resistors. I have thousands of electronic compts in the garage from my days at Motorola and Wavedriver (and my hobby days before that) but they seem to be mostly stuff like power MOSFETs, windings, ICs, cables, probes, finished products etc. I couldn't find a single collection of resistors or any sort.

Then I recalled buying a selection of assorted 1/4W resistors from Maplin a couple of years ago when we were living in the rented hovel a few miles from here. I was building up some Raspberry Pi stuff and needed some pullups and LED droppers. Phew.

Another 10 minutes trying to find some solder (in a Linbin with all the soldering stuff, where the various solder reels have always lived in plain sight).

Then strip and tin the wires, set up the PSU and scope and get ready for some moments of truth.

Here's the setup:

Looks as if the CNC gods are smiling again. This with a simple flick of the wrist spin of the spindle. I'll need to spin the thing up to a decent speed at some point but I see no reason why it should behave any differently then.

12V supply and 3.3k pullups

The waveforms aren't quite squarewaves, so I may need to adjust the gap between the sensor and the gear. Then bugger about a bit more with the phase angle (angular separation) between the sensors. But it looks hopeful.