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mcv
Joined: 16 Sep 2013 Posts: 13
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Posted: Thu Aug 11, 2016 7:09 am Post subject: Electribe 2/Sampler service manual |
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Hi
Does anyone has access or knows where to search for Electribe Sampler service manual?
I have broken component DT2 in power area, looks like a transistor, but probably not bipolar. It has number 24 written on it, which doesn't say anything. I want to replace it, but I can't find any service manual anywhere.
I'd appreciate it if anyone could help me with this. |
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mcv
Joined: 16 Sep 2013 Posts: 13
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Posted: Thu Aug 11, 2016 4:31 pm Post subject: |
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I investigated a bit.
The mark on the component is 24. With http://www.s-manuals.com/smd/24 I found it could be a TVS, zener diode or an NPN transistor. I decoded the PCB a bit and come up with this schematic, assuming that the broken DP2 component is NPN: http://imgur.com/a/0C2Nj
The "base" is connected to a logic trace that goes to the second "logic" board. It wouldn't make much sense for it to be a zener, or a simple pair of diodes. My hypothesis is that when power button is pressed, it powers up the CPU, and the CPU quickly forces high level on DP2's base, which forces low level on gate of nearby big CPH6302 MOSFET, which then powers the whole system. At any time, CPU may decide to power off the whole system simply by setting low level on DP2's base. I see similar stuff on service manual of microKorg, which I found on the Internet. ;-) Except that microKorg doesn't have power switch like electribe, so it doesn't have the same circuit. But otherwise it all makes sense, isn't it? ;-)
Nevertheless I confirmed my theory with a little experiment: when I press the power button when device is plugged in, it boots and works as long as I have power button pressed. When I release it, everything immediately turns off. It's because the CPU can't force power-on state by high level on DP2's base (because it's broken and, actually removed from the board altogether now).
So now that I'm pretty sure it's a simple NPN transistor, I have to replace it with something else and see if it works. Hmm… stay tuned? ;-)
Yeah, it feels stupid to talk to myself, when no-one has replied. |
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mcv
Joined: 16 Sep 2013 Posts: 13
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Posted: Thu Aug 11, 2016 5:23 pm Post subject: |
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It's damn fixed. I didn't have SMD NPN transistor, but I had logic-level N-channel MOSFET, and it it works just fine.
While I was fixing it I broke another component, diode D37. Mechanically. It rendered the 'Mute part' button useless. I can't even tell when this happened, but I think Korg should really improve quality of its products. Or buy better components, because current are just pure crap.
I have replaced it with THT 1N4148, works okay. But I've never encountered an SMD transistor or an SMD diode being physically broken so easily. :/ Not to mention that I found a number of little tin balls all over the main board - probably result of poor soldering automation.
Ehh, Korg.
Never mind, it works now and in case you're interested of what electribe sampler looks like inside, here's a gallery:
http://imgur.com/a/zEsqp
And a word to electribe 2/sampler owners - love them carefully. ;-) Those machines aren't forgetful. ;-) |
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Brawny
Joined: 15 Jun 2016 Posts: 5 Location: UK
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Posted: Tue Sep 20, 2016 5:05 pm Post subject: |
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I had a search, discovered this post, and it seems as though my unit is showing exactly the same issue as yours did with DT2 removed. It'll power up fine, but turns off instantly the moment I let go
I don't suppose you could provide a link to the part you bought could you?
Last edited by Brawny on Fri Sep 23, 2016 7:48 pm; edited 1 time in total |
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BubbleTrailsMusic Junior Member
Joined: 19 Aug 2016 Posts: 51 Location: Austin, Texas
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Brawny
Joined: 15 Jun 2016 Posts: 5 Location: UK
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Posted: Tue Sep 20, 2016 7:16 pm Post subject: |
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Something seems to have caused my ES2 to no longer switch on properly.
What's the fault with yours? Is it the same power issue?
Last edited by Brawny on Fri Sep 23, 2016 7:46 pm; edited 1 time in total |
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BubbleTrailsMusic Junior Member
Joined: 19 Aug 2016 Posts: 51 Location: Austin, Texas
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IImyment
Joined: 01 Oct 2016 Posts: 1
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Posted: Sat Oct 01, 2016 2:57 pm Post subject: |
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mcv wrote: | It's damn fixed. I didn't have SMD NPN transistor, but I had logic-level N-channel MOSFET, and it it works just fine.
While I was fixing it I broke another component, diode D37. Mechanically. It rendered the 'Mute part' button useless. I can't even tell when this happened, but I think Korg should really improve quality of its products. Or buy better components, because current are just pure crap.
I have replaced it with THT 1N4148, works okay. But I've never encountered an SMD transistor or an SMD diode being physically broken so easily. :/ Not to mention that I found a number of little tin balls all over the main board - probably result of poor soldering automation.
Ehh, Korg.
Never mind, it works now and in case you're interested of what electribe sampler looks like inside, here's a gallery:
http://imgur.com/a/zEsqp
And a word to electribe 2/sampler owners - love them carefully. Those machines aren't forgetful. |
Thanks you so much MCV,
Following the really good description of your es2 I managed to fix exactly the same thing on my e2 within less than half an hour.
If anyone is experiencing similar behaviour on theirs and they can't access a npn for a while it's still possible to bypass the switch using the unused jp right next to the power button that would do the job till you get a chance to receive your trany. |
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mcv
Joined: 16 Sep 2013 Posts: 13
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Posted: Sun Oct 02, 2016 4:56 pm Post subject: |
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Brawny wrote: | I had a search, discovered this post, and it seems as though my unit is showing exactly the same issue as yours did with DT2 removed. It'll power up fine, but turns off instantly the moment I let go
I don't suppose you could provide a link to the part you bought could you? |
The transistor I used is 2N7002, I usually buy my stuff here: http://tme.eu
http://www.tme.eu/gb/details/2n7002/smd-n-channel-transistors/fairchild-semiconductor/
The original is unknown |
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mcv
Joined: 16 Sep 2013 Posts: 13
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Posted: Sun Oct 02, 2016 5:04 pm Post subject: |
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BubbleTrailsMusic: No drops, no liquid. But my pads aren't working as they should - some need much more force to trigger than others. I opened the ES2 to see what I can do about that and that's when I probably broke those parts. Or they were at least partially broken already.
If you're doing live shows - did you think about a backup? Another ES2? If something happens, you could simply move your SD card with all your stuff to the second one and continue, right? |
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Armand
Joined: 08 Sep 2018 Posts: 1
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Posted: Tue Sep 11, 2018 4:29 pm Post subject: |
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IImyment wrote: | mcv wrote: | It's damn fixed. I didn't have SMD NPN transistor, but I had logic-level N-channel MOSFET, and it it works just fine.
While I was fixing it I broke another component, diode D37. Mechanically. It rendered the 'Mute part' button useless. I can't even tell when this happened, but I think Korg should really improve quality of its products. Or buy better components, because current are just pure crap.
I have replaced it with THT 1N4148, works okay. But I've never encountered an SMD transistor or an SMD diode being physically broken so easily. :/ Not to mention that I found a number of little tin balls all over the main board - probably result of poor soldering automation.
Ehh, Korg.
Never mind, it works now and in case you're interested of what electribe sampler looks like inside, here's a gallery:
http://imgur.com/a/zEsqp
And a word to electribe 2/sampler owners - love them carefully. Those machines aren't forgetful. |
Thanks you so much MCV,
Following the really good description of your es2 I managed to fix exactly the same thing on my e2 within less than half an hour.
If anyone is experiencing similar behaviour on theirs and they can't access a npn for a while it's still possible to bypass the switch using the unused jp right next to the power button that would do the job till you get a chance to receive your trany. |
First of all, thank you both mvc and IImyment!
I also managed to break the transistor while I was repairing the "unresponsive" pads. I put the Korg back together, and voilá, the power button behaved exactly the same and discussed in this topic.
I felt really frustrated (and still kinda do, as this turned out to be a horrible mistake, even the pads are now perfect).
I did some experiments, and yes, bridging the unpopulated J4 overrides the power on/off circuitry, but the device will be "always on" (well at least it works for now).
I wondered how on earth the D2 became broken/loose from the board, and I suspect the screen frame (white plastic) might have caused it, as you have to pull the board outwards so that the back connectors have space to come out, and while doing that, I ripped the transistor off while doing that.
Well, better see if I can fix it a bit better than the J4 shortcut solution.
So, my story short, be VERY careful when removing the main board |
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