- #1
Salvador
- 505
- 70
on the outputs (DC) from my smps after the bridge rectifier diodes and a smoothing filter cap bank I still get about 1V or bit more parasitics which I am almost certain are due to the very switching itself and not inductively induced from the EMI around the smps , I tested this with a scope whenever I put the probe leads across output wires whether ground or +- I get the parasitic waves on the screen on top of my flat DC. when i disconnect and simply fool around with other wires I don't get them , even when very close to the switching parts I still get very small induced spikes much smaller than the ones in the output wires.
I have two transformers each having a secondary and a mur1560 diode bridge and then filtering caps (6x1000uF/160v) per transformer.Also I got additional 100nF poly caps for additional filtering across the outputs and 15kOhm resistors across each transformers rectified secondary to keep the max idle voltage stable etc.Apparently this is still not enough and some ripple or whatever that is gets through, I mean I simply put the scope ground on one side of a fuse and the probe at the other side so that i measure directly across a fuse on either the outcoming + or - and across those 2+cm of wire I still get those parasitics , is there any way to get rid of them ?
otherwise everything is fine but these little spikes get through into my amplifiers and I can hear them in the speakers and that is not nice.I somehow thought about maybe a linear regulator at the output that could drop only a few volts from the output and maybe somehow filter out the noise ? Give me some advice.
P.S. sorry for the bad scope shots it's just that the scope itself is not exactly NASA technology and it's shot by a webcam.