www.megadrum.info

Hello

I've just built megadrum and already programmed the ICs. But when I connect it to the computer, using SuperiorDrummer sampler, it gets multiple sound, even though no pads are connected to the jacks. The LCD shows that it has some signal coming from the Jacks. I didn't use all inputs: only 1-9.

Here is a picture of how I wired the Jacks. The red wire is ground.


Can someone point it out where is the error?

Thanks,
Francisco.

Guesses from the limited problem description:
1. Incorrect R1,R4-R6,R26-R28 values.
2. Incorrect ground wiring.
3. Incorrect inputs wiring.

It seems to have been interference from the electric network (60Hz here).

However, I'm still facing some malfunctions. On the LCD display, the top left block is constantly high, even though no pad is connected. Is that right?

I also get some signal when I touch the multiplexer's pins or bridge the wires in each jack. But the connection with the pads doesn't seem to be working.

I think the problem is the connection from the board to the jacks. But the soldering on the jacks seem fine. The resistors have the right value.

Is there any configuration that I might be missing? Is the power from USB enough to make the pads work?

chicobatera wrote:It seems to have been interference from the electric network (60Hz here).

However, I'm still facing some malfunctions. On the LCD display, the top left block is constantly high, even though no pad is connected. Is that right?

Yes, it is right.

I also get some signal when I touch the multiplexer's pins or bridge the wires in each jack. But the connection with the pads doesn't seem to be working.

I think the problem is the connection from the board to the jacks. But the soldering on the jacks seem fine. The resistors have the right value.

Bad connection.

Is there any configuration that I might be missing? Is the power from USB enough to make the pads work?

Yes, USB power is enough.

Thanks dmitri, I'll try rewiring everything.

One last question: if I wired the jacks expecting stereo inputs and plug a mono P10 cable, it should work anyway?

chicobatera wrote:Thanks dmitri, I'll try rewiring everything.

One last question: if I wired the jacks expecting stereo inputs and plug a mono P10 cable, it should work anyway?

I'm not sure how to answer this. If the wiring from the piezo all the way to the input is right then it will work regardless if it is stereo or mono.

I finally managed to get one pad working, but instead of getting the kick sound, as I expected, I got the ride sound. Also, there's only one jack that seems to be working.

I sometimes get the signal of the hi hat closing, even when nothing is connected to it's jack.

I checked the wiring, it seems ok. I measured some voltage on all jack's terminals. But when i connect the pad to the working jack, and try to measure the voltage, i get 0V and sound form SuperiorDrummer.

Anyone knows what might be wrong?

Thanks,
Francisco.