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Messages - asji

#1
Tech Help - Projects Page / Re: Dirtbag v3205 signal loss
December 14, 2012, 05:06:37 PM
as it turns out, it pays to be stubborn :)

i checked everything, and found 1 trace gone 'missing', so fixed that. re-soldered and checked everything that looked suspicious, cleaned my board .. and i had repeats again!
At first i was scared a bit, because i still had distorted repeats.
But after tweaking the gain trimmers, there it was :) sounds brilliant now.
i found that gain1 in particular was responsible for the distortion i was still getting...
When setting the trimmers the first time, i gradually increased both gains simultaneously and by the time i got runaway feedback, the repeats were distorted. but by lowering gain1 a bit and increasing gain2, i got it to run away, with nice repeats.

thanks for the help
#2
Tech Help - Projects Page / Re: Dirtbag v3205 signal loss
December 12, 2012, 03:17:47 PM
Thanks for the quick reply.
Learned something again :)

The Gain trimmer was not turned up, i guess that's why i had no output at IC3... now i do.
But after the NE570, it's a very soft repeat i'm getting.. it's too weak i guess as an input for the next repeats.
I'm still working on it. But it's becoming a mess to be honest.
Pots have broken off, lost a few pads and i am not confident anymore about the stability of my board.
I am thinking of starting over however... a new board for the V3205 version, but in the meantime i have found 4 MN3008's, and i would also like to try that route.
I'll keep an eye out for when the boards are available again.
#3
Tech Help - Projects Page / Dirtbag v3205 signal loss
December 11, 2012, 11:05:22 AM
Hello.

It's been a while (received my board a year ago) since I've started with my Dirtbag.. and i got it working, but with the distorted repeats.
I think i had done just about all the mods (except the final revision) to get those repeats cleaner, so my board is not looking very pretty anymore... difficult to find errors...
Anyway, i decided to give the latest changes a chance, because it seems people are building v3205 versions without distorted repeats.
Now all parts are as the latest revision says they should be.
After these latest changes however i am not getting repeats at the output.
Now the part where i'm confused...

I used my audioprobe to follow the signal path.
I have output at both BBD's and i can follow the output of the last BBD up to R31. before R31 i have a signal, after none.
i checked R31. It's 680k, so fine.
i checked for shorts in this area, nothing...
also resoldered those joints.
so now i have no idea how to continue... i should have a signal there no?

hope someone can help.

greetings,

Antoine