SOLVED Hydra - Deadish?

zachlovescoffee

Active member
Hello team PPCB!

I just finished my Hydra build last night. Sick looking pedal and pretty easy to put together except that VF-1 chip. Man that was fun to solder on. I dipped the feet in flux and used a wide "blade" tip and that seemed to really work well and make the job easy.

Okay, so, why is it dead? No freaking idea. I have bypass signal, sounds fine. When I turn the pedal on it introduces some low level hum but I get absolutely no effect.

I did some test measurements at various chips and I am getting voltages. Does anyone have the schematic for this pedal so I can see some reference voltages? Or, does anyone have a listing of various reference voltages?

When the pedal is off I get zero Ohms between the input and output jacks. When the pedal is *on* I get ~ .890 MoHms between those two. Don't know if that matters, just throwing out some troubleshooting I did.

I also re-flowed every single solder blob and cleaned the whole board with contact cleaner. Any thoughts on what to do next or have some reference values?
 

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You might want to reflow the solder on these pins of the FV-1. However I must say, your soldering looks pretty dang good for the first time soldering one.

1642436672567.png

However, if you get no clean/dry signal when the pedal is on there's another issue... the dry signal doesn't pass through the FV-1.
 
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First rule of trouble shooting - make sure your jacks are in the right way. 2nd thing - make sure the level control is up.

You have already reflowed so next I’d check components to make sure every value is correct.

Some of those pins on the FV-1 could possibly do with a bit more solder
 
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Audio probe.

This is now the second fairly complicated build you are having issues with.

After the rudimentary checks, it should be your next stop.
 
You might want to reflow the solder on these pins of the FV-1. However I must say, your soldering looks pretty dang good for the first time soldering one.

View attachment 21737

However, if you get no clean/dry signal when the pedal is on there's another issue... the dry signal doesn't pass through the FV-1.
Definitely have output dry and wet. Just no effect. Makes me think it has to be the VF-1 or the EPROM? Will re-flow just to re-check!
 
If reflowing doesn't help temporarily solder a jumper wire between these two points.

If you get effects (it won't be the Hydra) we can consider the EEPROM the problem.

If you still don't get an effect signal you can rule out the EEPROM as the problem.

1642437588467.png
 
If reflowing doesn't help temporarily solder a jumper wire between these two points.

If you get effects (it won't be the Hydra) we can consider the EEPROM the problem.

If you still don't get an effect signal you can rule out the EEPROM as the problem.

View attachment 21739
Thank you Robert! I’ll start with re-flow on the VF1 and then try some of the other troubleshooting and also this as a last restart.

I have an audio probe built so I just have to haul my amp into the garage. I need a Blackstar Fly3 to keep on my bench so I don’t have to move my 69’ Princeton reverb around all the time.
 
Re-flowed the solder on the VF1 and that did it. I also gently pressed the iron onto the leg and consequently onto the board. I think that helped a lot too.

I was able to get amazing sounds kit of this thing. This is the sickest delay I’ve ever heard. It’s inspiring to play. Tapestries of delay, echo, reverb…omg

The only thing is that I’m getting some noticeable hum. Could be because the pedal is outside of the enclosure but I wonder if you gurus have any thoughts?

 
If it's hum it might be the lack of shielding from being unboxed.

The FV-1 isn't a dead silent IC, but that is generally in the form of white noise.
 
@zachlovescoffee you might benefit from some smaller projects to get a hang of the off-board wiring and other circuit elements. It seems like you’ve jumped into the deep end with complicated projects. Once you’re confident with the fundamentals and basic use of the multimeter, it’ll be easier to troubleshoot any issues that may arise.
 
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