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Hello all,
I'm purches a Full Kit , and build it after the instruction ( theoretically easy ).
I connect my new box via USB with my computer, switch box on, and the LCD is fine, the potis work too when I turn it.
To test the jacks ,I connect a piezo with a stereo cable. When I touch the piezo there is no signal on the VU.
The red LED is still out. I tried all inputs with the same result.
Any tips to locate the problem?

br

Jörg

Most likely you connected the piezo to wrong wires. Make sure you use correct ground wires. Take a picture of where you connected the piezo to the flat cable and, if you unplugged the flat inputs cables after unpacking the parcel, how you plugged the cables back.

Hello,

here some pics about the connections, hope you can see something.

I try most of the jacks and change tip and ring but I got still no signal.

You're connecting the piezo to tip and ring: wrong.

On a stereo input:

Piezo 1 goes to tip and sleeve

Piezo 2 goes to ring and sleeve

The ceramic part of the piezo normally goes to tip/ring and the brass part to sleeve, though I don't think it matters much.

I test different combination (Ring, Sleeve, Tip) with the piezo > no Signal.

At last I connected a new Roland CY5 Cymbal> no signal.

I think something with the connection is wrong....

Can somebody see something on the pics?

br Jörg

Show how the flat inputs cable is connected to the board and mark two wires on it which you believe are ground wires.

Ok, I marked between 15 & 16 in red...

The upper and the lower jackrow are connected on sleeve with the longer red cable on the left site.

Pin 1-4 are not used.

br

Jörg

1. Did you test it with only one piezo?
2. What happens on the LCD if you touch one of the input pins (which is not connected to a piezo) with something metallic, e.g. tweezers, held with a bare hand? You may want to hold another hand close to some electromagnetic signal source, like a bulb of a lamp, to induce parasitic signal on the input.

1. I try it with
-a brand new CY5 cymbal
-two different single piezos
-without stereo cable - connected direct on the jackpin > no sigal

2. as you suggest I touch the jackpin with an little fullmetal srewdriver, and I got a short peak on the VU and red led.
The signal is not permanent only a peak, even when I let srewdriver on the pin.

Nepo wrote:2. as you suggest I touch the jackpin with an little fullmetal srewdriver, and I got a short peak on the VU and red led.
The signal is not permanent only a peak, even when I let srewdriver on the pin.

I guess by the jackpin you mean a pin on an input jack and not the pin on the board. In this case:
1. Unsolder one input wire from one input jack.
2. Unsolder both ground wires from the jacks.
3. Solder a piezo to this one input wire and one of the ground wires.

After that tap the piezo. What do you see on the LCD? If you don't get a VU meter signal/MIDI LED, with a multimeter test for continuity between one of the ground pins on the board and both ground wires on the flat inputs cable.