# Creamery Buzzing



## IPv6Freely (Jul 28, 2021)

LED comes on, but there is nothing but a low volume buzz through my amp. Another day, another pedal that doesn't work...

Board pre-pots:






Solution for pots not having pins narrow enough to fit into PCB holes:





Final assembly:





Do you see anything obviously wrong?


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## Feral Feline (Jul 29, 2021)

D1 is in backwards. 
Q1 transistor is in backwards — probably, depends on its pinout.


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## IPv6Freely (Jul 29, 2021)

Feral Feline said:


> D1 is in backwards.
> Q1 transistor is in backwards — probably, depends on its pinout.


FML. I noticed Q1 and swapped it. I didn't notice D1. 

I really need to be more careful building these things. Components being wrong or the wrong orientation is inexcusable.


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## IPv6Freely (Jul 29, 2021)

Okay, now Q1 and D1 both fixed. Still just buzz, and only while the COMPRESS knob is turned beyond half way, otherwise nothing at all. Bypass is fine.


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## music6000 (Jul 29, 2021)

It really is Wurth going over the PCB thoroughly & and checking orientation if it doesn't fire up!
That IC 4 looks suspect the way it's sitting.
How did you determine which way THAT 2159 goes?


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## IPv6Freely (Jul 29, 2021)

music6000 said:


> It really is Wurth going over the PCB thoroughly & and checking orientation if it doesn't fire up!
> That IC 4 looks suspect the way it's sitting.
> How did you determine which way THAT 2159 goes?


That's a good question. I guess I should check the datasheet on the THAT2159 because I have no idea and made an assumption there. 

I'll take a look at IC4


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## IPv6Freely (Jul 29, 2021)

Yeah looks like the THAT2159 are the right way. Pin 1 is on the left, and according to the datasheet pin on the left is IN and the schematic confirms that.


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## IPv6Freely (Jul 29, 2021)

IC4 reseated as well... no change. I guess its back to checking voltages and continuity...


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## music6000 (Jul 29, 2021)

IPv6Freely said:


> IC4 reseated as well... no change. I guess its back to checking voltages and continuity...


Can you recheck your Pot legs are all connected to the PCB via the leads???


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## IPv6Freely (Jul 29, 2021)

music6000 said:


> Can you recheck your Pot legs are all connected to the PCB via the leads???


Yeah that will be the first thing I check - knowing that it's a bit of a hack job its the most likely thing to be an issue.


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## music6000 (Jul 29, 2021)

IPv6Freely said:


> Yeah that will be the first thing I check - knowing that it's a bit of a hack job its the most likely thing to be an issue.


Where did you get that J201?


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## IPv6Freely (Jul 29, 2021)

music6000 said:


> Where did you get that J201?


eBay...


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## Feral Feline (Jul 29, 2021)

music6000 said:


> It really is Wurth going over the PCB thoroughly & and checking orientation if it doesn't fire up!
> ...


Not the Wurth thing possible to go wrong, though — at least the magic smoke is still contained.


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## IPv6Freely (Jul 29, 2021)

I tested the J201 I got and I'm getting the correct values for Idss (0.27mA) and Vgs (0.79V) so it shouldn't be the J201 that is the issue.


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## music6000 (Jul 29, 2021)

Test for Continuity on these Matching colours:


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