Roland BK9 will not power on

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I went to turn on my bk9, and it will not power up. I tried a different power adapter and nothing. however, the power adapter is for a yamaha mofx8. help!
 
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I went to turn on my bk9, and it will not power up. I tried a different power adapter and nothing. however, the power adapter is for a yamaha mofx8. help!
Well, I checked the specs for the adapters you used:

BK9: 9 Volt, 2.0 amp, center NEGATIVE
moxF8: 12 Volt, 1.5 amp, center POSITIVE

They are not compatible. So there is a possibility that you hosed the circuit board. You might be saying hello to a new paperweight.
 

happyrat1

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It might have a reverse polarity diode or a zener that fried to protect the motherboard.

It's not a cheap ass Casio or Yamaha.

At this point, take it to a good tech for repair.

A good tech will be able to tell you in 15 minutes if it can be saved or not.

The original problem might have been as simple as a loose internal wire but now you'll be spending some bucks for sure to see IF it can be saved and HOW MUCH will it cost?

Gary
 
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It might have a reverse polarity diode or a zener that fried to protect the motherboard.

It's not a cheap ass Casio or Yamaha.

At this point, take it to a good tech for repair.

A good tech will be able to tell you in 15 minutes if it can be saved or not.

The original problem might have been as simple as a loose internal wire but now you'll be spending some bucks for sure to see IF it can be saved and HOW MUCH will it cost?

Gary
I only tried the yamaha cord after no power with roland cord.
 
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Well, I checked the specs for the adapters you used:

BK9: 9 Volt, 2.0 amp, center NEGATIVE
moxF8: 12 Volt, 1.5 amp, center POSITIVE

They are not compatible. So there is a possibility that you hosed the circuit board. You might be saying hello to a new paperweight.
I only tried the yamaha cord after keyboard wouldn't power on with roland adapter. I dont think it even reached all the way in. I have a tech buddy that thinks it's probably a fuse. I HOPE! Thanks for reply. YIKES!
 
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It might have a reverse polarity diode or a zener that fried to protect the motherboard.

It's not a cheap ass Casio or Yamaha.

At this point, take it to a good tech for repair.

A good tech will be able to tell you in 15 minutes if it can be saved or not.

The original problem might have been as simple as a loose internal wire but now you'll be spending some bucks for sure to see IF it can be saved and HOW MUCH will it cost?

Gary
Thanks gary. Definitely not cheap. I don;t think the yamaha cord made full contact, and the keyboard wouldn't turn on with the roland adapter to begin with. Thanks for the replay. My buddy believes it to be a fuse. Or I'm sending it to you!
 

happyrat1

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Old style fuses are less than effective for protecting digital circuits these days.

More likely there's a fusible MOSFET and resister or two near the power supply which sacrificed themselves to protect the motherboard.

At any rate, the second you connected the wrong supply and flipped the switch you definitely destroyed that component regardless of whatever other issues you might have had earlier.

If you're a gambling man I call 50/50 odds... :)

Gary ;)
 
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Old style fuses are less than effective for protecting digital circuits these days.

More likely there's a fusible MOSFET and resister or two near the power supply which sacrificed themselves to protect the motherboard.

At any rate, the second you connected the wrong supply and flipped the switch you definitely destroyed that component regardless of whatever other issues you might have had earlier.

If you're a gambling man I call 50/50 odds... :)

Gary ;)
I'm an idiot. I'll pass this on. If he can't fix it, I'm not sure where to go with it. Any ideas that won't take a year or two to fix?
 
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Nope, I have a Gemini module in need of repair. I've been waiting for parts since June and they are due to come in the next one or two months. It's not a tech issue for me; it's a parts sourcing issue.
 

happyrat1

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I'm an idiot. I'll pass this on. If he can't fix it, I'm not sure where to go with it. Any ideas that won't take a year or two to fix?

Actually there's a 50% chance there was a reverse polarity rectifying diode in the circuit when you plugged in the wrong adapter.

If so, then no additional damage was committed and no harm no foul.

As for the original problem, it may well be as simple as a loose internal wire or cold solder joint.

Also, THE VERY FIRST THING in any diagnosis is to inspect and diagnose any power supply issues.

Only then do you move on to systematic troubleshooting.

If the Motherboard is getting normal power then you know the problem is more complicated.

If you live in any sort of major metropolis, there's bound to be a qualified music tech who can do a proper repair and not waste your money doing a punk diagnosis and writing it off immediately.

A lot depends on the quality of the tech you hire.

My suggestion is to check out your local Ham Radio Club and circulate your need for a tech there.

Those guys know their component level repair and can bring back almost anything from the dead.

But, as Dave mentioned, sourcing parts can be a time-consuming task.

If you really don't feel like writing off a $1200 board there's always Ebay and other sources where you can swap out the entire motherboard if you can't locate and identify the problem.

All I'm saying hope springs eternal and nothing worth doing is done in a hurry... :)

By no means is it a writeoff yet. You have options to explore.

Gary ;)
 
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A few points here...

* There are numerous connectors for power supplies, and if your Yamaha adapter didn't fit in the Roland's opening, chances are good that it never made contact and so no damage would have been done, regardless of the power spec of the adapter.

* As for whether using the Yamaha could have damaged the board if indeed it did make contact... possibly, but not necessarily. Connecting a 12v adapter to something that expects 9v is unlikely to cause damage. Connecting a center-positive to something that expects center-negative could possibly cause damage, but as mentioned, often won't. Plugging a 1.5 amp capable adapter into something that requires a 2.0 shouldn't damage it... but it also probably won't work, because it's probably not capable of delivering enough power for the device to operate. BTW, this is a case where specs actually don't have to match... you can always use an adapter with a HIGHER spec for amperage, just not one that is lower. Basically, if a board draws 2 amps of power, the power supply has to supply a minimum of 2 amps of power. Having an ability to supply more won't hurt, but less won't do the job.

* Your instincts were right that the first thing to try would be a different power adapter. It just has to be one of the correct spec. Since odds are you did not damage anything by trying to connect the Yamaha adapter, the best thing to do next is pretend you never even tried. Just get a hold of an appropriate adapter (whether a Roland, or a universal that you can set appropriately) and see if that fixes your problem.
 

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