hall sensor for hihat input wiring diagram.

[Rob]

eDRUMin samples the pedal input at 10 bits, and then applies filtering to make the signal stable.

I would like to pick up some hall sensors so I can do some experiments. Can you recommend some part numbers so I can pick some up from DigiKey?

[dsteinschneider]

Hi Rob,

These are the ones I bought (my order was for a 10 pack - each was about $1.00 USD:
https://www.amazon.com/gp/product/B07DW ... UTF8&psc=1

There are two variations of the A1302 - some that are like a switch - they only output two values so act like a switch - the others output a range of values which is what the ones I bought do. I'm mentioning this because once in a while someone will report that their hi-hat DIY build isn't sending a range of CC04 values because they bought the wrong version. I think they call the two value version "latching".

I guess the A1302 is out of production

Here is Digikey's Hall Effect Sensor search return:
https://www.digikey.com/products/en?t=554

User ignotus on vdrums is good at sourcing stuff like this from places like digikey, aliexpress etc

[mprinz]

Hi Rob, hi dsteinschneider,

I ordered the Honeywell SS495A linear, analog, TO-92.
Similar to that ordered by the starter of this thread.

I read a few articles on Hall sensors and I learned this:

There are sensors with linear voltage output depending on the magnetic flux and switches that only toggle the output (I guess they are called digital, what makes sense). But those can be unipolar, reacting only to one pole of the magnet or bipolar, switching on both poles of magnets.
The non-latched sensors are switched on only during a magnetic flux going through. The latched ones keep the switch state without magnetic field and you need to give magnetic flux to change the state. And I guess there are also uni- and pipolar versions. So to toggle the state you need a certain magnetic pole.

Wooow... . eDrums are quite complex... My friends are calling me a nerd. Just because reading Hall sensor, piezo, MIDI crap in my freetime.

Hmm, now I am think of using the Hall effect for triggering cymbals... Or some capacitives devices... Anyway, thats another thread.

Regards

[Polyphonics]

This is great, I should change mine to be more similar to this one

I need to buy some new hall sensors so can anyone confirm which are the best? I'd like to have one that has a good distance of 4-5cm and is actually linear (my one has a curve where it has more sensitivity the closer the magnet is)

[Rob]

You are not going to get a linear response from a linear hall effect sensor. A linear hall effect sensor outputs a voltage proportional to the strength of the magnetic field, however the strength of a magnetic field is not proportional to distance.

That being said, if you mount it off to the side a bit, you should be able to get something more linear.

[mprinz]

Ahh, Rob! That's right. And I am talking about nice linear response. But I just saw those nice linear voltage vs. gauss diagramms and yuur...

So we need a linear magnetic field. Some large coils, or...
eDrums in an NMR device... Here,you have large, strong linear magnetic fields.

So, back to a linear pots?There must be a reason why the new FD-9 only has rebuilded mechanics and electronically there keep to press a
hopefully linear to the distance responding film resistor. The FD-9 has a sheet of metal pressing, no longer the rubber part.

Did anyone try some freaky resolver, encoder stuff...

[Rob]

If you set the magnet off to the side slightly, the distance from the magnet to the sensor will change exponentially as the hats come down, thus giving you a close to linear voltage response.

[mprinz]

Hi Rob,
sorry? Just let the magnet pass the sensor at a side so neither let the magnet facing the sensor directly nor even touching it when completely stepping the pedal down?

Besides: In january I took apart the standard millenium hihat controler to put some grease on and that is actually an solution using an optical barrier. But they use only a plastic rail with, I remember max. 5 or 6 slits. Corressponding with the jumping CC04 data.

Greetings

[Rob]

I think I'm going to order part number SS49E because it's low voltage operation means that it can be powered directly from the eDRUMin pedal input. Are most users powering their hall effect sensors externally?

[Polyphonics]

You are not going to get a linear response from a linear hall effect sensor. A linear hall effect sensor outputs a voltage proportional to the strength of the magnetic field, however the strength of a magnetic field is not proportional to distance.

That being said, if you mount it off to the side a bit, you should be able to get something more linear.

Interesting, more linear movement would be good, I think putting aside that anomalous bug I have, edrumin is the best hihat controller I've ever used.

I'll try this off-centre mounting and see how it goes.