I've been using the Wahoo quite happily using battery power for the last year. Over Christmas I decided to build a proper pedal board and switch to using a power supply.
I found that with the power supply attached the pedal was extremely noisy in the signal chain. The power supply has isolated outputs and has a 9v 500mA output. As a test I tried with a different 9V power supply(single wall plug) with the same result. As a further test I completely removed the batteries and in this case the Wahoo is unusable. The LEDs are on but as soon as you take the pedal out of bypass it just creates a load of noise and there is no guitar signal coming through the pedal at all. This suggests to me that there is something wrong with the power supply input on the pedal rather than a power supply issue. Any suggestions? Thanks.
Wahoo only working with batteries
Re: Wahoo only working with batteries
That is very odd. The power from batteries, USB and 9V DC are combined then fed into the power supply circuits. So if something is wrong on the 9V supply, there aren't many things that can go wrong so it should be easy to fix.
Can you check on USB power? Does that work (note that you may get noise when powering from a computer because of ground loops; laptops on batteries, or plug-in USB phone chargers work too).
Another thing you can check is the measured voltage inside the Wahoo. You can do this using a test procedure as follows:
(1) Power on the Wahoo while pressing 3 things: FILTER button + LEVEL knob + SAVE button. The display will shoe "-E-" to indicate you are in a special test mode.
(2) Release those buttons and you will see "t01". Press the UP button until you see "t07". Press SAVE.
This runs a special test (number 7) which shows the internal voltage. For a 9V supply it should show around 8.20. Please try this and let me know what it shows.
You need to unpower/repower the Wahoo to get back to normal operation.
Can you check on USB power? Does that work (note that you may get noise when powering from a computer because of ground loops; laptops on batteries, or plug-in USB phone chargers work too).
Another thing you can check is the measured voltage inside the Wahoo. You can do this using a test procedure as follows:
(1) Power on the Wahoo while pressing 3 things: FILTER button + LEVEL knob + SAVE button. The display will shoe "-E-" to indicate you are in a special test mode.
(2) Release those buttons and you will see "t01". Press the UP button until you see "t07". Press SAVE.
This runs a special test (number 7) which shows the internal voltage. For a 9V supply it should show around 8.20. Please try this and let me know what it shows.
You need to unpower/repower the Wahoo to get back to normal operation.
Re: Wahoo only working with batteries
Also noisy with USB.
I took out the batteries and ran the voltage test with my board power supply. The read out was fluctuating in the range 8.34 to 8.38.
I was going to try this with a second power supply to see if I got similar results but I can't now put in into the test mode again.
When I boot on the device I am now getting the Er1 message flashing before startup. I'm pretty sure it wasn't doing this before I ran the test.
I took out the batteries and ran the voltage test with my board power supply. The read out was fluctuating in the range 8.34 to 8.38.
I was going to try this with a second power supply to see if I got similar results but I can't now put in into the test mode again.
When I boot on the device I am now getting the Er1 message flashing before startup. I'm pretty sure it wasn't doing this before I ran the test.
Re: Wahoo only working with batteries
I have an idea as to what the problem is.
There is a filter resistor on the power between the digital and analogue boards. I suspect this has developed a fault. "Er1" is an error code indicating the analogue board couldn't power up correctly. I suspect the voltage on the analogue board has been dropping and that's why it got noisy, and eventually gave the Er1 code.
I can't explain why it was ok on batteries, presumably just coincidence.
It's a very easy fix you can do yourself if you have tools, or we can do it for you.
There is a filter resistor on the power between the digital and analogue boards. I suspect this has developed a fault. "Er1" is an error code indicating the analogue board couldn't power up correctly. I suspect the voltage on the analogue board has been dropping and that's why it got noisy, and eventually gave the Er1 code.
I can't explain why it was ok on batteries, presumably just coincidence.
It's a very easy fix you can do yourself if you have tools, or we can do it for you.
Re: Wahoo only working with batteries
I'm guessing the term "easy fix" is relative and depends on your skill with a soldering iron!
Can you describe the fix and then I can decide whether to attempt it myself or return it. Thanks.
Can you describe the fix and then I can decide whether to attempt it myself or return it. Thanks.
Re: Wahoo only working with batteries
Indeed, you need to have the tools to do this and some skills!
See the attached image. Open the bottom of the Wahoo to remove the baseplate and you will see both PCBs facing you.
I suspect R123 is faulty. It should measure 4.7 ohms. If not, this is certainly the problem.
It's just a case of removing that and replacing it. There's quite a bit of space around it so it's easy to get to with a soldering iron.
Either replace with a another 4.7 ohm resistor, or 2x 10 ohms in parallel.
Let me know what you think. If you need me to send you a few resistors, I can do that (are you in the UK?).
See the attached image. Open the bottom of the Wahoo to remove the baseplate and you will see both PCBs facing you.
I suspect R123 is faulty. It should measure 4.7 ohms. If not, this is certainly the problem.
It's just a case of removing that and replacing it. There's quite a bit of space around it so it's easy to get to with a soldering iron.
Either replace with a another 4.7 ohm resistor, or 2x 10 ohms in parallel.
Let me know what you think. If you need me to send you a few resistors, I can do that (are you in the UK?).
- Attachments
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- Wahoo Analogue board (R123)
- Analogue_PCB_R123.png (115.27 KiB) Viewed 9285 times
Re: Wahoo only working with batteries
What is the process/cost for returning to you to fix? I'm in the UK (Scotland).
I'd prefer not to start dismantling the PCB just in case I damage it (and also in case this doesn't resolve the issue and there are further fixed required).
I'd prefer not to start dismantling the PCB just in case I damage it (and also in case this doesn't resolve the issue and there are further fixed required).
Re: Wahoo only working with batteries
If you post it back to me (I am Scottish, but based near Cambridge) I'll check it for you and do the repair and get it back to you. No cost if you pay to send it to me. I'll send you a PM with the shipping address.
However, The NAMM Show is next week (we are leaving on Tuesday) so I might not get time to do the repair before I leave. If you prefer to send it so it gets to us the following week, I'll make sure it gets repaired and back to you very soon. If you send it before, there will be someone to get it (just not someone to repair it!)
However, The NAMM Show is next week (we are leaving on Tuesday) so I might not get time to do the repair before I leave. If you prefer to send it so it gets to us the following week, I'll make sure it gets repaired and back to you very soon. If you send it before, there will be someone to get it (just not someone to repair it!)