Use a hall sensor as HiHat-Controller

[tis]

Hi,

i just received my MD32. I just tried to use a hall sensor (Honeywell SS495A1) as HH-Controller.

What happens is the following :

- Using a switch or resistor at port 1 of the MD works flawlessly.
- The sensor works on the breadboard without a problem with 4.9V power supply.
- When connect the sensor to the MD (Vcc-Tip, Vout-Ring,GND-Sleeve), Vcc drops from 4.5V to 0.5V and the MD does not read any values.

Does anybody got a clue what could be going on and how to solve the issue ?

br tis

[dmitri]

Power on the HiHat controller jack is provided over a 100 Ohm resistor (for protection from short circuit) so if the sensor draws too much current for power then you have to use a separate power supply for it.

[tis]

Hmmm, slightly better.
But now Vout seems to be pulled up to 4.5V from the MD and only uses the range from 4.5V ... 4.9V (very near). When I switch the MD off the sensor works normal and uses the range 0...2.5V,2.5V...4.9V depending on the polarity of the field.

Tried a different Sensor (A1324) but similar effects and the sensor got hot ...

Any idea ? From the past I read that some People easily manged to get this working just by soldering a Sensor directly to a cable at port 1 w/o any additional parts ... Maybe a different sensor type ????

[dmitri]

I wonder how it can get hot with 50mA of current at most. Anyway, if it gets hot it is very likely you use wrong polarity.

[tis]

Suddenly it works when you start doing it right .....

After spending one hour with the schematics I found out, that the pinout I used was wrong. I got this one from an old forum post (Vcc-Tip, Vout-Ring,GND-Sleeve).

The correct pinout is : Vout-Tip, Vcc-Ring,GND-Sleeve !

[dmitri]

Vcc-Tip, Vout-Ring,GND-Sleeve is polarity for Yamaha HiHat controllers.
Vout-Tip, Vcc-Ring,GND-Sleeve is polarity for Roland (and most others) HiHat controllers. This how I wire it in MegaDrum unless I'm asked to wire it for Yamaha.