Electric OU: SSMicroToroidal QEG 1: Decade Counter Coil Driver

This is an illustration of a circuit that a poster on OU dot com designed to drive 8 coils in a simulated rotary sequence.

ERRATA: At about 1:20 I say “PNP” but I’m using NPN transistors for this demo. At about 4:00, Pin 14 is tied to Positive rail and 15 is tied to Ground and Clock to Pin 13 for TE clocking, and I change to LE clocking by tying 13 to Ground and Clock to 14.
ERRATUM 2: After looking more carefully at the OP’s photo of his breadboard, I can now see that he has indeed implemented a jumper from Pin 15 (reset) to Pin 9 (ninth output). This will eliminate the 2-output “gap” and make the counter cycle smoothly through 8 outputs rather than 10. Sorry about my confusion, hope this clears that matter up.

The circuit uses a 555 timer to create a clock pulse, which drives a 4017 decade counter through its sequence. 8 of the outputs of the decade counter are used to drive the bases of 8 NPN transistors in a high-side switch arrangement, which then are intended to drive 8 coils in sequence.
[s]The original design only uses 8 of the 10 outputs, so there is a gap or stutter in the simulated rotation. [/s] Sorry, see Erratum 2 above.

I’m using LEDs instead of coils here to show what the circuit does.

In the OP’s design, the eight coils are wound in a double-cruciform manner and this is inserted in the center of another coil that is wound in a toroid or circular fashion.

The simulated rotation and switching of the 8 driven “primary” coils induces a voltage in the toroidal or circular secondary, which the OP thinks will be sufficient to drive a voltage converter module which will then power both a light-bulb or other load, and the coil driver circuit itself, without any outside source of power. Yeah, right, good luck with that !!

In the video I also illustrate how to make the 4017 respond to the trailing edge of the clock pulse as the OP had it, or to the leading edge of the pulse, whichever is desired.

Also, using PNP transistors in the high-side switch inverts the outputs, so you would have all coils or LEDs on with a dark one sequencing through the 8 outputs. (Not shown in this video.)

I may go ahead and make the coil structure at some point, but for now, this illustration of the driver is enough to chew on for the moment. Let the fallout begin!

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