String Ringer V1.2 Debugging

[dileobass]

http://www.diystompboxes.com/smfforum/index.php?topic=97115.0

Hello fellow pedal enthusiasts. I have currently completed this build from the V1.2 schematic.

it is a cool pedal and is working reasonably well, all knobs and switches work as i assume intended and the sound is pretty gnarly with great characteristics that are fun to improvise with. 

The only small problem i am having is the ringmod is passing a fair bit of frequency noise across which modulates with the freq. knob, this is happening when no signal is put thru the pedal.

On the daughter board with the transformers and diode array i have used 1n4148 diodes, i read in the above post that BAT48 diodes are good in ringmods, would changing to these diodes 'clean up' the stray frequency noise in the ringmod? other than this i cant see any way that this problem could be improved.

cheers
Dan

[digi2t]

The BAT diodes will definitely improve the octave. As for the noise, have you tried adjusting the trimmer to null out the noise?

[dileobass]

Hey thanks for the reply digi2t 

i will try the BAT48 diodes, i am not getting any change at all with the trim pot it may not be any good as it was a used item.

will try to get some pics up soon

cheers
D

[BetterOffShred]

Deadend FX string ringer board, the red one, no version info on board

So I'm getting around to this finally and I have a question that doesn't appear to be addressed in the November 2018 build guide.   

R3 is listed as 100k-1M but it doesn't really say what the philosophy is here.  Is there a procedure I should follow to size this appropriately?    It doesn't seem to be mentioned in Markus' 1
2 document either from back in the day.

Anyway I just figured I'd ask thanks
-Brett

I didn't see a thread for this build yet so I figured I'd tack onto this one. If I should start a new one let me know

[PMowdes]

Deadend FX string ringer board, the red one, no version info on board

So I'm getting around to this finally and I have a question that doesn't appear to be addressed in the November 2018 build guide.   

R3 is listed as 100k-1M but it doesn't really say what the philosophy is here.  Is there a procedure I should follow to size this appropriately?    It doesn't seem to be mentioned in Markus' 1
2 document either from back in the day.

Anyway I just figured I'd ask thanks
-Brett

I didn't see a thread for this build yet so I figured I'd tack onto this one. If I should start a new one let me know

Brett,

We should probably update the document, I've advised people to use a 1M.  Dino can probably tell you why.

[BetterOffShred]

Alright excellent!  1M it is 

[Kipper4]

What I like about this guy BetterOffShred is that i'm sure If you followed my posts in order of creation you would find the paths similar.

I hope you get it going mate and learn some too.
I tried to do a string ringer once and never did manage to make it do what I thought it should.
I hasten to add it was not a ready made pcb but a perfboard hack.
Good luck.