I ran a sine sweep wav through it whilst monitoring what the deck was seeing and there's some oddness at 3000hz and below. It's fine via line in and it's not the coil or amp. There's an odd transition kick that shows up as a double trigger like the deck is attenuated at the lower end of the range 🤔
It works spookily well. The readout is me flicking the filter switch on and off. It is most definitely doing its job and has taken everything I have thrown at it.
I've got some square wave fettling to work on but once that's sorted then I reckon it'll be done. ☺️
To tweak it, I'm looking at the result that the deck 'sees' rather than a read across the coils. Once I'm happy I'll dial it in with recorder justage and see where the ideal filter point is. 🙂
To get the best from the Bluetooth amp, I've made an 1100 turn coil. It can handle the full range and I've used a smaller DC blocking cap to limit the lower end.
I'm working on filtering out the wobble. well I was, until the battery ran out.
The charge level is a neat little feature though! 🥳
...or get the specific gravities of the two fluids to match, and use an electromagnetic coil at each end wired in opposition to each other - it should in theory just wobble about nicely. 🙂
I'm generally pretty chill but using a system that I know has been enshittified on purpose is beyond infuriating. It wastes a users time and patience and even if it took only an extra 10 seconds to do something that 10 seconds X the whole user base = Years of wasted time 😔
I say better because it looks like a proper circuit diagram as opposed to my 'bunch of stuff thrown together in Kicad that any self respecting PCB manufacturer would go cross-eyed and laugh at' 😂
Actually, someone did a better one - github.com/jameshpdp/Sp... Joules mentions using a 7nf cap in his video but used 20nf as he didn't have any 7nf caps - Apparently this deals with the frequency sensitivity and 7nf may get you a better range. 🙂
This is the best I can do for now, It's basically an adaptation of the JoulesperCoulomb Schmitt trigger but with a Bluetooth module lobbed in. I'll see if I can get some more details later. 🙂
