Keeps blowing circuit module!! :(

Hi,

First time on here, so please be nice!

Ive bought around 10 of these MP3 trigger devices from ebay

I thought simple, Put a 5v supply on it, and away I go.

And I was right, I installed one, plugged it in to some powered computer speakers, and all worked well. Exactly how I expected.

I installed the next one, with a small 12v supply that plugs into a mini amplifier, and also plugged into the same transformer, is a 12v to 5v converter. (I also tried 12v 5v USB transformer)

First time, I could smell smoke, and noticed the small microchip below the headphone jack, went bang. Plugged in another one of these units, and all went well as expected. Has been powered on now for over a month, and has been used 100s of times. Still working perfectly.

came to the next one, and exactly the same setup, and first of all, I tried with the small speaker that it gets supplied with, and all went well. Plugged in the mini amplifier, and it went bang. Tried 2 more units, and the 3rd one worked, and has been fine ever since.

I played around with the remaining units, and found that if the amplifier, and the 12v-5v step down that plugs into this unit, are both plugged in to the same transformer, it blows that same chip every time.

if i plug it into separate transformer, it works first time every time (so having a seperate 12v supply for both the amplifier, and the 12v-5v step down to this unit) Hae tested this time and time again, and works every time. Moment I plug them into the same transformers, it blows.

Ive tried different amps, different 12v-5v transformers, tried different 12v transformers. I just dont get it.

the transformer is supplying 12v at all times, and the 12v-5v is supplying a steady 5v at all times. (according to my multimeter.

The transformer is adjustable, and is set to 12v and is rated at 5A. Ive tried multiple transformers. Sopme cheap and not so cheap.

Please help me out!

Thanks

Guy

 

H

hi, Thanks for your reply.

http://www.ebay.co.uk/itm/100V-240V...hash=item5b134c6022:m:mYqt1sXsY2BKMzV0NH75R0A

This is the power supply I purchased.

http://www.ebay.co.uk/itm/DC-DC-Con...321733?hash=item25ad1fa345:g:M1UAAOSwqv9V7Wx6

This is the 12-5v

It does have something written on the chip, but I cannot make it out at all even with a magnifier.

If I use two of these power supplies, one for the amp, and the other for the 12-5v all is good :/

 

Thinking about what you said, the first one that i installed all went ok, and i was using a 12v 500ma adapter from an old cctv camera.

Worked first time.

I think it may well be the 12v transformer.

Problem is, I now have 10 of these transformers. Is there any way I can make it less noisy? Would be abit of a waste on money!

thanks again

Guy

 

Thanks for your input.

Here is a link http://www.ebay.co.uk/itm/MP3-Voice...119546?hash=item210274a4ba:g:L5cAAOSwiLdV9rps

 

Ahh. Yeah I connect it to a mini 60w amplifier to connect to some large speakers
Needs to be quite loud. Weird, as I've got one working perfectly with this exact setup. Kill 2 prior to that, so must be lucky with that particular module. Wonder how long it will last.

This makes sense, as it works good with powered computer speakers too.

Is there any solution? Apart from using two power supplies?

 

Hmm, Also, it says you can connect an amplifier to it in the description.

 

Hi, Yes I only use the 3.5mm jack.

I only got the 12-5v due to price, and the fact that it is physically small. These are going to be contained in a ip rated external box. The 12v transformer was cheap enough, and was trying to get it as small as possible with only one 240v input, and 12v output. If you get me!

I also tried a in car 12v usb charger. Did exactly the same thing.

I just got what suited the budget you see. Turns out something isnt right!

Ill try and get a photo of what it is exactly, but trust me, it is very hard to see even magnified!

Thanks for your help chaps!

 

Also, Ill just add.

The volume adjust seems to control the 3.5mm jack, aswell as the speaker output.

Not sure if that is anything relevant, or not

 

W

Would there be any way to fix this?

Also, It does state in the description that an external amp can be used

Thanks

 

This may sound really stupid...but is there any way I can make it not share a ground? What's the best workaround?

Im away from these units until tomorrow, but will check continuity then.

Thanks

 

Although I dont hzave access to my multimeter etc untill tomorrow, I do have some High res photos that maybe youi could take a look at?