Minnow with 2 inverted J201

Dali

Well-known member
I'm so used to having all the caps with positive on the same side with PedalPCB that I just put 2 J201 (Q4,Q5) on the wrong orientation.

No I'm not blaming PedalPCB, he don't come at my house putting them backward, I did...

The question now is did I damaged my J201 (Q4-Q5)?

Once I've put them back the ENV switch seems ok but the when in S/H position, the sounds drop a bit and I'm way away from what I was expecting (Zappa's Ship Ahoy).

Both leds work as expected, controls work too it's really just not "intense" at all.

1627154125290.png
1627154153747.png

Link to docs: https://docs.pedalpcb.com/project/PedalPCB-Minnow.pdf
 
Ah. Yeah, definitely something wrong there.

Take a look at the attached. I marked up the points on the schematic that you'll want to be aware of.

The three devices I've outlined in red are the three poles of the three pole double throw mode switch.

All three switches are ganged: that is, they are mechanically linked to switch in unison. Therefore, there are two ways to draw the circuit. It is currently drawn with A2 connected to A1, B2 to B1, and C2 to C1. If that switch is flipped, A2 connects to A3, B2 to B3, and C2 to C3.

As drawn, the circuit is in sample and hold mode: this part of the circuit I have outlined in blue. The envelope portion of the circuit is outlined in green.

That's a long preamble there, but necessary to illustrate one fact: Those two blue trimpots inside your pedal are mechanically disconnected from the circuit in envelope mode. They shouldn't effect the envelope setting at all.

Could you have mistaken the switch modes in your trimpot test?

The trimpots are interactive and take a bit of tweaking. To my ears T1 sets the "range" of the steps and T2 sets the...uhhh...effected- ness. Not sure what to call it. S&H absolutely won't work without tweaking those trimpots, and either one set to the extremes will cause the S&H function to be inaudable. If you start with T1 halfway and T2 at minimum, slowly increase T2 until you start to hear steps. From there, listen and tweak until you balance out the filtered highs and lows.

It's more "to taste" than science, truthfully. Which is seriously my least favorite way to adjust these things. Always makes me want to leave the back off an enclosure cause I'm much better at the setting Screenshot_20210725-141746__01__01__01.jpg
 
Ah. Yeah, definitely something wrong there.

Take a look at the attached. I marked up the points on the schematic that you'll want to be aware of.
Thanks a million for such great explanations. I will have to digest it all 'cause I'm a "builder-by-numbers" but I will take time to understand the circuit and schematic for sure.

Thanks again for your time. I will report tonight if my brain isn't already burned by my crazy schedule at work.
 
Stupid newbie question: Is the 3PDT Mode switch got a special orientation? I didn't really check before soldering since all the other switches I ever use on PedalPCB boards don't have a specific orientation.
 
Stupid newbie question: Is the 3PDT Mode switch got a special orientation? I didn't really check before soldering since all the other switches I ever use on PedalPCB boards don't have a specific orientation.

From my experience they don't... I was puzzled at the first few build how that could be, but after a min of thinking I figured it was just a on on switch that is push push... so regardless you put it on when you push and on when you push again... that's my understanding anyway :)


---- Awaiting to be corrected ! :p
 
Back
Top