No Joy in Joyoland

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No Joy in Joyoland

Postby pablomago » 01 Jul 2013, 21:27

I have a Joyo Digital Delay. When you turn it on it works fine but within a few minutes, the effect stops working. The LED is lit, sound goes through, but there's no delay. It happens with a power supply or with batteries. I've been told the switches aren't too good on these. Any thoughts, ideas or suggestions for a fix?
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Re: No Joy in Joyoland

Postby square wave » 01 Jul 2013, 21:46

My bet is the PT2399 is overheating and locking up. To diagnose, I would:

1. Unbox the unit enough that you can get to the IC's.
2. Plug the pedal in.
3. feel the PT2399
4. play until it locks up
5. feel the PT2399 again - if it's warm/hot, that's probably your problem.

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Re: No Joy in Joyoland

Postby atreidesheir » 02 Jul 2013, 02:19

Square wave is 100% probably correct.
Nice sounding unit when it works.
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Re: No Joy in Joyoland

Postby Dirk_Hendrik » 02 Jul 2013, 07:17

The PT requires 5Vdc supply voltage. Verify this voltage to be available when delay is present as well when delay is gone. Might be a 78L05 type regulator shutting down when overheating.
Sorry. Plain out of planes.

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Re: No Joy in Joyoland

Postby pablomago » 02 Jul 2013, 19:26

I haven't disassembled the pedal to test it yet, but it looks like there's almost no solder where the battery connects to the circuitboard. When I get a chance, I'm going to resolder that connection. Does anyone think that could be the problem? (It'd be nice if it were a simple fix)
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Re: No Joy in Joyoland

Postby square wave » 02 Jul 2013, 20:22

That specific connection causing the failure? Probably not, because if it were a power connection problem, the pedal would never work. However, bad soldering somewhere else on the board could be causing your (presumed) overheating problem.
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Re: No Joy in Joyoland

Postby pablomago » 17 Aug 2013, 05:42

I finally got my tools so I could take this thing apart. No heating on the IC. It was dead cold. The delay effect is no longer working at all. I didn't test voltage on the IC, I'll get to that soon. It still passes signal either on or off. Just no delay. I tried to retack the wires between the switch and board and three came unsoldered. With my old eyes and no magnifier, I didn't want to retack them until I can find a way to see them better. I don't want to make things worse. I'll have to get one of those little stands with the clips and magnifier.

That's where it stands today. Any more ideas?
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