Mooer Ocean Machine troubles [FIXED]

[camarada78]

Anyone experieced with Mooer Ocean Machine pedal? It is pretty sophisticated and mine have some issues.

First i got full bypass sound, but after some "work" it is fully without sound (lol). Still turns on and all controls seems fine.

What i had:
- Regulator WRA1209 giving the correct voltage (+9v, -9v). which seems correct
- 117 regulator receiving +9v, it was delivery 8.5v. Seems wrong cause the adjust resistor are 1.3k and 475 (should be 4.7v)
- burning hot CS4272 converter receiving 3.2v on Digital Voltage IN and 8.5v Analog Voltage IN. Changed.
- no obvious caps or resistor burned. Only a Cap on the 117 regulator circuit around 25% wrong value, changed.

After changing the 117 twice, I got 5.3v on output (the first one was 6.6v weirdly); The resistors values (1.3k and 475ohms) "should" make a 4.7v output, and the resistors are fine. But 5.3v its not that far from theoretical 4.7v.

The datasheet for the CS4272 says Digital Voltage In should be 3.3 to 5v but the Analog Voltage In should be the same value as Digital Voltage IN +0.3V, so one of them is wrong.

Since i dont have a schematic i dont know if the Digital Voltage IN should be around 5v or the Analog voltage should be 3.3v.

Any clues?

 

[Khron]

I think page 9 of the CS4272 datasheet spells it out pretty clearly, in the "Specified operation conditions" table.

https://statics.cirrus.com/pubs/proDatasheet/CS4272_F2.pdf
Analog, 4.75-5.25V (nominal 5V)
Digital, 3.1-5.25V (nominal 3V)
Logic, 2.37-5.25V (nominal 3V)

"Analog input voltage" refers to the signal going into the ADC inputs, not the supply voltage to the analog side of the converter. And that's in the "absolute maximum" section anyway.

Are those 1.3k and 475 ohm resistors, definitely measuring what it says on them?

There's a good chance the CS4272 wasn't the only chip powered from that overvolted 5V rail...

 

[camarada78]

ah, thanks for the clarification.

The resistor are measuring 1.280 and 468 ohms. in and out of the board.

I will order a new CS4272 because i think the second 117 (that weirdly gave 6.6v) fried the new cs4272 i installed. shame.

 

[camarada78]

UPDATE: FIXED

The 117 broke giving wrong tensions all around burning the CS4272 and a capacitor. Changed both and it returned to work. It is fixed.

 

[Jarno]

Interesting pedal, but I can imagine repairing it is quite a daunting job, kudos!

 

[camarada78]

My tips for anyone fixing them:
All can be checked without the control board attached, just the main board and power supply.

1. check if the power supply has juice enough. Mine here had 9v 1A which is way above needed. check polarity of said PS.
2. Check voltages on WRA1209 for 9v and -9v
3. check voltages on the 117 for around 5v. It should receive around 9v and output around 5v.
4. Before installing a new CS4272, without it installed measure 117 for the 5v needed. I burned one because of a bad new 117.
5. when changing CS4272 use alluminum tape or capton to protect the plastic stuff, specially the white relays, mine got a little "deformed". lol

tools needed:
- hot air station
- flux
- solder (duh)
- a microscope does help to check if the joints are good.
- thermal camera saved me a lot of time. the hottest component should be the WRA1209 with around 40-50 celsius.

 

[bbryant82]

Similar issues with my Ocean Machine, no output when engaged. All of the components listed measure correct on mine, however there is still no audio output when engaged. I was able to hear my dry signal while recording a loop, but the playback was a noisy garbled mess. Would any of this lead you to check elsewhere for faulty components? Or maybe my CS4272 is still bad, but not because of any regulators being off. It does not burn hot, but can you tell me how to check the CS4272 chip with a multimeter? Cheers and thanks!!

 

[camarada78]

A multimeter just measure if its receiving the correct dc voltage (Kron posted the datasheet above), its worth checking.

Do you have a signal tracer? check if audio is getting into the CS4272 and out of it. I had other pedal effect here with also a burned CS4272, it appears to be a common fault in these chips.