SP-F Batteries

**FozzFoster** · 09-30-2021, 11:14 AM

and here's a Wheatstone diagram (Wikipedia):

Attached Images

**FozzFoster** · 09-30-2021, 11:15 AM

Maybe I should stop talking haha cause this might very well be beyond my comprehension haha I'm no electrician.
But to me they both look like 'Wheatstone' circuits...

**FozzFoster** · 09-30-2021, 12:24 PM

Originally posted by stevebrot

The differences between the circuits is obvious on the diagrams.

It seems to me that the earlier spotties do have a wheatstone, but their system is measuring differences of resistance to a specific known voltage (voltage dependent; 'R2' would be calibrated to a known voltage resistance.

It seems to me that the SPF has a 'modified wheatstone', modified because they add those funky dual coils, and the system is instead comparing differences between the current (magnetic field) coming from those coils. Since an increase in voltage would affect each coil equally, the system is not voltage dependent..

I'm really swinging above my weight here though...

**FozzFoster** · 10-23-2021, 02:12 PM

follow up correction video:

Youtu.be

09-30-2021, 11:15 AM	#17
FozzFoster Custom User Title Join Date: Jan 2016 Location: Alberta Photos: Albums Posts: 6,808 Original Poster	Maybe I should stop talking haha cause this might very well be beyond my comprehension haha I'm no electrician. But to me they both look like 'Wheatstone' circuits... Attached Images Last edited by FozzFoster; 09-30-2021 at 12:55 PM.

09-30-2021, 12:24 PM	#18
FozzFoster Custom User Title Join Date: Jan 2016 Location: Alberta Photos: Albums Posts: 6,808 Original Poster	Originally posted by stevebrot The differences between the circuits is obvious on the diagrams. It seems to me that the earlier spotties do have a wheatstone, but their system is measuring differences of resistance to a specific known voltage (voltage dependent; 'R2' would be calibrated to a known voltage resistance. It seems to me that the SPF has a 'modified wheatstone', modified because they add those funky dual coils, and the system is instead comparing differences between the current (magnetic field) coming from those coils. Since an increase in voltage would affect each coil equally, the system is not voltage dependent.. I'm really swinging above my weight here though... Last edited by FozzFoster; 09-30-2021 at 01:26 PM.

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09-30-2021, 11:14 AM	#16
FozzFoster Custom User Title Join Date: Jan 2016 Location: Alberta Photos: Albums Posts: 6,808 Original Poster	and here's a Wheatstone diagram (Wikipedia): Attached Images