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bergnoise / BABY

baby-5 sequencer for eurorack
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problem in 4 step mode? #1

Open KeLaiFu opened 5 months ago

KeLaiFu commented 5 months ago

I've built this sequencer and it's almost working perfectly except it seems to just hold the 4th note for 2 notes in 4 step mode rather than looping back to step 1. I've checked my soldering and all seems ok, although I could have missed something. Is this fault down to me, or is it something in the original design?

edit I am not sure if its behaving differently now, or i was just mistaken but upon trying it again today, the 4 step mode infact seems to be playing 5 steps with an additional silent step before it loops back to step one.

bergnoise commented 5 months ago

Is it sending the gate out twice on step 4 or does it simply need to be fed two input gates to step forward again? I've had the issue that the input clock needs to be fairly clean (i.e. be a square-lfo that only oscillates between 0 and positive voltage) otherwise there will occasionally be steps in between. Apart from that, I'm not sure what the issue could be, I basically just copied this design and made minimal changes from the original design (the mkx edu one). My knowledge of electronics is fairly limited and I only built one of these and haven't tested it extensively. But a friend of mine built several and did not have this issue. Have you tried changing the 4017?

KeLaiFu commented 5 months ago

Thanks for the reply. I don't know if I am losing my mind or it's behavior is changing but upon testing it again, it actually seems to play a five note sequence when the length switch is set to 4, then it doesn't send gates for the next 5 (so its silent if I'm using the gate too open the VCA), then it plays the 5 note sequence once again before repeating its silent loop once again.

I'll go over the soldering and maybe replace the 4017 though, since you confirmed the module is fully working.

bergnoise commented 5 months ago

This sounds like the issue is located either at the switch or the CD4017 as it does not seem to reset properly when you set it to 4 steps. If it works as intended on 3 or 5 steps, the issue is likely with the switch and/or the routing. My best guess is that you have the same issue that I had when I first started this project where i used the wrong DPDT switch as there are two types (see: https://www.seymourduncan.com/blogs/wp-content/uploads/Switches2_Diag_4.gif)

If you want to check this possibility:

I changed the board in a revision: Version 1 uses Type 2 switches The Revision uses Type 1 switches

The wiring was changed in between the revisions to match the type of switch and is marked on the PCB. The easiest way to check (assuming you used the same batch for both switches) is if your Range switch changes correctly between ~1,2 and 5v. Otherwise, check the board and your switches with a multimeter (or check out the board files)

edit: Oh and also make sure you actually have a on-on-on DPDT switch, as there is also a type on-off-on switch that does not have the proper connection in the middle (see: https://www.seymourduncan.com/blogs/wp-content/uploads/Switches2_Diag_2.gif)

KeLaiFu commented 5 months ago

I think the switch could be it, the range switch seems to go low - high - medium range, rather than low - med - high. I just pulled a couple from the drawer so I have no idea which type they are.

I will grab some on-on-on ones and try it. Fingers crossed.