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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

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.

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 ????

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.

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 !

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.