Hi dannix, thanks for posting.
I used a db155g briIdge rectifier IC. I thought since it is a BRIDGE rectifier, it must be full wave. Is this not so? Using this IC, I managed to remove the negative part of the AC signal, which is unfortunately far from what I would like to achieve.
I've built a diode rectifier bridge (4 diodes, full wave rectification), but I didn't think in advance and forgot that diodes drop around .6V. When I connected this to the piezo vibration sensor, I got a flat 0v out all the time, since the output of the sensor is always below .6V, therefore the diodes were dropping all the voltage.
Finally, do you believe this is as simple as putting a bridge rectifier IC on the piezo sensor output to achieve what I'm after?
I was looking at suppliers in my area but the choice for bridge rectifier ICs is very limited. I can get the db155g that I mentioned, WO4 and a 2W06. Would any of these be acceptable?
Thanks for help!
-Igor