# Low Tide Envelope Problems



## bobbass4k (Jun 9, 2021)

Final parts arrived for the low tide and unfortunately its not been plug and play. The envelope/LPG part of the circuit isn't behaving, I'm only getting sound if I really dig in and then it just pushes it into momentary self oscillation. Altering the gate trimmer just changes the point at which it self oscillates? 

Anybody had any similar issues before I go through it with a fine tooth comb? The 13700 and 3207 are known good and there's nothing obvious I can see...


----------



## benny_profane (Jun 9, 2021)

Without a schematic, there isn't a lot that can happen with signal tracing. Have you confirmed your values and verified your soldering? Pictures would also be helpful.


----------



## fig (Jun 9, 2021)

I am possibly having a similar issue regarding the gate. I am able to produce the effect but the clamp is way to prominent. Just chillin until the schematic arrives.


----------



## bobbass4k (Jun 10, 2021)

Values all OK, no issues with the soldering. Gonna try and follow the signal path best I can with an audio probe and see if there's any joy. 

I guess I can understand the reasoning from a commercial perspective, and I knew it was risky, but without schematics the complex projects like this are just way too risky, I won't be doing it again.


----------



## Robert (Jun 10, 2021)

bobbass4k said:


> I guess I can understand the reasoning from a commercial perspective



There's no marketing ploy involved, it's just a huge schematic that needs a lot of attention before posting.


----------



## bobbass4k (Jun 11, 2021)

Robert said:


> There's no marketing ploy involved, it's just a huge schematic that needs a lot of attention before posting.


Any ETA? Or if it's just a matter of formatting would you be willing to message/email me the raw version?


----------



## Leftovernoise (Jun 11, 2021)

bobbass4k said:


> Final parts arrived for the low tide and unfortunately its not been plug and play. The envelope/LPG part of the circuit isn't behaving, I'm only getting sound if I really dig in and then it just pushes it into momentary self oscillation. Altering the gate trimmer just changes the point at which it self oscillates?
> 
> Anybody had any similar issues before I go through it with a fine tooth comb? The 13700 and 3207 are known good and there's nothing obvious I can see...


Ok this might be a stupid question but where do you have the lpg knob set? All the way to the right is no filter, all the way to the left is very filtered. Also the trimmer does cause the lpg to act weird unless you have the trimmer in the sweet spot zone, which for my unit is the last 25% of the trimmer, clockwise.


----------



## michaeldustdevil (Jun 11, 2021)

is there an image for parts location on the pcb anywhere?


----------



## fig (Jun 11, 2021)

Here you go
https://docs.pedalpcb.com/project/LowTide-PedalPCB.pdf


----------



## michaeldustdevil (Jun 12, 2021)

thank, but that is just part values, i need part #'s... R1, R2, R3... C1, C2, C3... etc...


----------



## Robert (Jun 12, 2021)

Redownload the build docs now.


----------



## michaeldustdevil (Jun 12, 2021)

still no joy... say i want to check continuity on R24 (for example), which of the 10K resistors is it?


----------



## michaeldustdevil (Jun 12, 2021)

@ PedalPCB... thank you!!!


----------



## bobbass4k (Jun 13, 2021)

Think I've tracked it to the LM258 - swapped it for half an LM324 via some flying leads and it's suddenly come to life. LPG is still behaving a little odd but I'm getting wet signal that isn't just self oscillation so I'm going on the right direction. 

I'd still appreciate an ETA for the schematic, if possible.


----------



## Robert (Jun 17, 2021)

I'll have it posted in the next couple days.      

It's a large image and needs to be rearranged a bit so everything fits on a single page without scaling it down to the point of being unreadable.


----------



## Robert (Jun 24, 2021)

It's taking me a bit longer than expected to get this added to the build doc PDF... 

Until then, here's the schematic:
https://docs.pedalpcb.com/project/LowTide-Schematic-PedalPCB.pdf


----------



## bobbass4k (Jun 24, 2021)

Muchismas Gracias, looks like I've got a wild evening with the audio probe and oscilloscope in store.


----------



## michaeldustdevil (Jun 25, 2021)

cheers for that too!... makes a big diff...


----------



## Feral Feline (Jun 25, 2021)

HUZZZAHHH!


----------



## Stickman393 (Jun 27, 2021)

Got a different question related to this...

The BOM calls for BAT48's, I'm about a quarter through my build and I realized that I've got BAT46's in there 

Specs seem similar RE: forward voltage, but at this point in my learning journey I'd trust my ability to interpret data sheets about as far as I could...

Well, I guess "throw it" works in this scenario too.

Whatch'all think?  Would a BAT46 act as a suitable substitution here?


----------



## bobbass4k (Jun 9, 2021)

Final parts arrived for the low tide and unfortunately its not been plug and play. The envelope/LPG part of the circuit isn't behaving, I'm only getting sound if I really dig in and then it just pushes it into momentary self oscillation. Altering the gate trimmer just changes the point at which it self oscillates? 

Anybody had any similar issues before I go through it with a fine tooth comb? The 13700 and 3207 are known good and there's nothing obvious I can see...


----------



## twebb6778 (Jun 27, 2021)

BAT46 and BAT41 are both good alternatives. I used BAT41 with no problems at all.


----------

