ms-20 filter clone

[jano2358]

hi!

I found your schematic of the ms-20 filter clone on the net and (i try to attach it for reference, but the button 'add an attachment' don't works) i'm trying to make it. The filter works, i don't know -yet- if the sound is similar to the original, i have one for compassion but i still can't take it off the work table because it insist in receive a radio station (only when the 'antenna' is enough -ie my body-) , it does by the cv cutoff (i was able to take off from there with 47nF in the travel) and for the line in too, this is the problem, i can't put a big condenser in the line in or in the travel of the signal and is becoming a little nightmare now. The problem seems to come from the filter itself, i de-attach the feedback with no results, added some negative feedback with condensers (until 1nf) with no results. It happens to you some like this? do you have some hint to solve this? should i do a completely new layout? (i doubt on this because the board by itself is quiet). Thanks in advance

[haima]

have you tried putting it inside a metal case, with the case connected to 0v at one point?

[jano2358]

hi!

i was able to remove it by putting a single pole (passive) filter in the input line with a 300ohm resistor and 4,7nf, this not affect to the audio frequencies the ccutoff is around 100khz, thanks for attention anyway