Power adapter for pedal, AC VS DC...

[lazyfinger]

I got this adapter from ebay, which said 9V DC adapter on the description:
http://www.ebay.com/itm/250907840817

I purchased assuming that I could power my pedals, like Boss DS-2, but it doesn't work. I tested the Boss and other Behringer pedal I have with 9V battery, and the pedals work, however, it doesn't work with that adapter.

I noticed that on the adapter it said, output: 9v, 1A. But it doesn't say DC. I tested the adpater with multimeter, and it did read 9.2 VDC and 19.2 VAC approx.

Are my pedals malfunctioning then? Then why would they work with 9V battery and not the adapter? If it's something wrong with the pedals, how do I test it or fix it?

 

[misterwhizzy]

Re: Power adapter for pedal, AC VS DC...

A 9V battery is DC. To step down a 120 V AC signal to 9V AC, all you need is a transformer. I don't think anyone would sell you just a transformer, calling it an AC adapter. I'm pretty sure you got the right thing, dude. Don't sweat it.

 

[lazyfinger]

Re: Power adapter for pedal, AC VS DC...

Thanks.

But why wouldn't the pedals work then? Any way to test the pedals to see if it's working right? Like I said, with 9V battery it works. And it used to work with another 9v dc adapter I had, but that one died.

 

[misterwhizzy]

Re: Power adapter for pedal, AC VS DC...

Could be the solder joint holding the AC adapter socket to the board. Typically, they connect at the same point somewhere on the PCB. If you're skilled enough to look around for it, you may be able to find where the two come together. Try resoldering that joint. Or just use batteries.

 

[GuitarDoc]

Re: Power adapter for pedal, AC VS DC...

Some adapters are negative core (inner) and positive shield (outer). Some are the opposite. Your pedals are probably negative core, so you may have to reverse the wires of the adapter. Just cut the wires and reverse them and solder them back together.

 

[lazyfinger]

Re: Power adapter for pedal, AC VS DC...

Some adapters are negative core (inner) and positive shield (outer). Some are the opposite. Your pedals are probably negative core, so you may have to reverse the wires of the adapter. Just cut the wires and reverse them and solder them back together.

You mean reverse and solder the wires on the plug tip?
I also tested that said adapter on a phone set that uses 12V DC adapter, and it was working with this 9v adapter.

Are there any instances where the pedals work with battery but not 9v dc adapter? I would understand if one short circuited, but both of them is acting up.

The pedals are Boss DS-2 Turbo Distortion. and Behringer Ultra Shifter Harmonist.

 

[lex666]

Re: Power adapter for pedal, AC VS DC...

Some adapters are negative core (inner) and positive shield (outer). Some are the opposite. Your pedals are probably negative core, so you may have to reverse the wires of the adapter. Just cut the wires and reverse them and solder them back together.

I agree with the Doc.

If everything is in working order, the plug polarity is probably reversed. That's why it works on other items. Be sure the tip is negative like shown here:

 

[lazyfinger]

Re: Power adapter for pedal, AC VS DC...

Thanks guys, looking at the symbols, I see that the Behringer pedal (and may be Boss too... it has no symbol to show for it) has negative inner, and the adapter has positive inner. So the adapter has to have negative inner then?

 

[lex666]

Re: Power adapter for pedal, AC VS DC...

Yep. Center negative, barrel positive.

 

[GuitarDoc]

Re: Power adapter for pedal, AC VS DC...

Just cut the wires on your adapter a few inches from the plug that goes into your pedals. Reverse the wires and solder them, so the negative will now be positive into the plug, and the positive will be negative into the plug. Tape it up and you're good to go.

 

[ratherdashing]

Re: Power adapter for pedal, AC VS DC...

Some adapters are negative core (inner) and positive shield (outer). Some are the opposite. Your pedals are probably negative core, so you may have to reverse the wires of the adapter. Just cut the wires and reverse them and solder them back together.

This was my guess as well ... and unfortunately if this is the problem, he's probably blown his pedal by plugging it into this adapter.

 

[lazyfinger]

Re: Power adapter for pedal, AC VS DC...

This was my guess as well ... and unfortunately if this is the problem, he's probably blown his pedal by plugging it into this adapter.

Not yet....:laughing:

But ironically on previous occasion, Boss DS-2 caught fire and partially melted/disfigured the circuits from high voltage. Another adapter issue, but pedal was fried. Then one day it came back from the dead on its own.

Guitar doc and lex666 advice worked like a charm. Not only they figured out the problem, they helped me to wire it right. Both pedals are working with this adapter now. You guys are geniuses! Thanks.