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I just went to wire up a 12v 2.1ah battery to a brand new MAH3 amp from Guitar Fuel and after a few seconds...smoke and a dead amp. I thought I got confused and mixed up the polarity so I VERY carefully wired up the battery to my second MAH3.... SHIT...two dead amps.

They say it can take between 9 and 15 volts and I hooked the battery up to the 9v battery clip wires. I may be mistaken but Id swear the power switch wasn't even on.

I tried contacting guitar fuel but have heard nothing back.

Anyone have any ideas on what I should do to check things out to see if there is any salvaging that can be done?

I feel absolutely sick about this...please help!

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That sucks, no doubt. I am not electronically savvy enough to suggest anything to check. Do you have a standard 9v battery you can use to test and make sure they are totally fried?

I wouldn't think 12 volts would fry it, but maybe 2000mah was too much? I dunno.

 perhaps it was solderered wrong??

 

check out this website on makeing homemade amps, its might help down the road, http://radio-guitar-amps.blogspot.com/

It was all per soldered.

I checked them both...dead.

I thought it would only draw the amps it needs...maybe I'm wrong?

I don't get it unless the 9 volt battery input is strictly for 9 volts and the adaptor power input is the one I should have used?

Here is a picture from one of our other members, is this the amp and the diagram for the one you have?

http://www.cigarboxnation.com/photo/img-1141?context=latest

and you hooked the power source/batter up to the one in the top middle of the diagram?

Yes it is and that's where I hooked up the 12 volt battery.

Well, pewp. Then I don't know what to suggest. I guess you have to wait to hear back from them.

Sorry, that was kind of expensive, eh?

they wont take anything other than 9-v  There is no going back  Go to ebay & contact Ty @ the gas gear store  Not sure he is going to replace 2 boards if you did the same thing to em  Next time use a standard battery or a 9-v converter rated at 500mah

wes

To be honest I was going off what Guitar Fuels site actually says...

http://guitarfuel.com/MAH3_Amplifier_Harness.php

"5-15VDC INPUT
 (adapter not included)"

...and that I was told in an email personally that 12v would give a more powerful output, generally speaking.

I thought I screwed up the first time by hooking up the battery the wrong way around and I could live with that...my bad. The SECOND time I was very careful and I don't recall the power being on (although I could be mistaken). After a few seconds...puffft... And that was it.
I've been trying to get in touch with Ty but have got no response so far...granted its only been about 20hrs but when you are sick with disappointment and rage at your own stupidity that 20 hours seems like a week.

500mah?

If it says 9 to 15v then a 12v source ought to be fine. All the stuff about battery capacities (ie. the figs quoted in mAh) is largely irrelevant to the problem in question. The circuit will draw a current dependent on the voltage applied across it - and it seems the voltage you applied was well within the specification.

On the face of it they have a case to answer and you shouldn't beat yourself up over it (although perhaps you should check the instructions for any small print that says not to connect 12v batteries where you did - it's distantly possible there's a built-in voltage regulator that works on the mains adaptor input but not on the battery input).

Also, if you can lay your hands on a voltmeter it's worth checking what the actual voltage is on the battery terminals. (That's because ratings such as 1.5v, 9v and 12v are only nominal. The true voltage tends to be slightly different - although I'd be surprised if it was sufficiently different to take you over 15v)

To figure out more I'd need to know the details of the components used in the circuit. Also, whereabouts exactly did the smoke come from? (ie. can you tell me whether it came from a particular component on the circuit board?)

Obviously it looks like they used at least one component that had a maximum design voltage below 12v. I'm guessing maybe a capacitor, but it could be something else.

Check to see if you can see any voltage figures printed on any of the components (especially the electrolytic capacitors, which are the cylindrical things between the pot and the intergrated circuit chip)

Also, can you see any writing or numbers printed on the chip? If we can identify the chip then it should be possible to find and download a datasheet that will say what voltage range it was designed for.

One further thought - are you sure you got the polarity right when you connected the battery?  If you connected it the worng way around then it's quite possible you cooked the electrolytic capacitors as they don't like reverse voltages.

If it's the capacitors that have been knackered then in theory you could probably remove them and solder new ones in their place, however that would require good soldering skills.

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