No spark. 1981 Ford falcon

Help me out with my fundamentals

We have a classic ford Falcon with an aftermarket 351 Cleveland V8 installed. It broke down while driving and is a crank no start- no spark condition.
There is no ground trigger on the coil.
There is an aftermarket ignition control module fitted. I don't have a pinout for the module so I just tested power and ground for now then moved to inspected the pickup in the distributer.

Here is the photo of the distributer ( photos.app.goo.gl/P7y2nrX1N1Sagzu49 ) and I've attached the output signal. There is voltage on the wire with ign on and the sensor produces a 1.5V ripple in this voltage while cranking. I'm pretty sure that this is where the no spark is coming from as I can't see an ECU being able to understand that signal.
But I'm confused by what sensor this is. There are only two wires going to it which I though can only be an analogue sensor which creates its own voltage. So why am I seeing battery voltage on one wire?
If its a hall effect sensor should I not see three wires? If it helps the sensor itself is magnetic.

I think I'm missing something obvious.

I've resolved this.

If anyone is interested the sensor was a magnetic pickup type. The pickup was working correctly and producing a 1.5V sinewave when cranking. The reason I was seeing battery voltage was that the ignition module was faulty and putting voltage on the line that it shouldn't have.

Thank you for the feedback.