Newbie Potentially Fried Board

[Cart]

So I picked up an AKAI MPK25 (a controller for music) and got a great deal because the usb was ripped out of it, but i was able to power it up and figured since I was starting soldering around the same time this would be a great test to repair and profit if I didn't really get into it as I have a number of other hobbies.

So I ordered some type b usb female connectors to replace the broken one. I used flux because the type b usb has small holes that i was having trouble clearing out, but eventually got through it all and was able to mount (poorly) the usb to the board. In a rush of excitement plugged in the usb cable to the device and to my pc that powers it up without wiping or cleaning off the flux, and it worked for 10 seconds just fine, until it didn't. It still show signs that power is getting to it when plugged in, but it's not operating correctly, as if it it is only receiving a very small or minimal amount to show any activity and my computer does not recognize it. This happens when I use the power cable as well. So, it's worse off than when I started working on it today....

Basically I want to know if I fried this thing or if I can somehow save this and have one successful project...

It can be powered via usb or a 6v DC connection. Both of those power inputs show signs of life and I wasn't sure what was going on at first until i heard a sizzling sound and I have yet to plug it in since.

I am new to all of this and view it as a valuable skill and fun hobby, but today has been nothing but failure on all 3 of my soldering projects sadly. So please help if you can, though I think I fucked this poor guy up...

 

[dorke]

Welcome to EP.

Yep, could be you did damage this unit.
The label on it says "6VDC", yet you say you used "9V".

Other than that, you should remove all those tiny solder splashes to prevent shorts.
Use an old toothbrush and clean well with rubbing-alcohol .

To learn how to solder properly,
visit the "EP resource" on it here

 

[Cart]

Welcome to EP.

Yep, could be you did damage this unit.
The label on it says "6VDC" ,yet you say you used "9V".

Other than that,you should remove all those tiny solder splashes to prevent shorts.
Use an old toothbrush and clean well with rubbing-alcohol .

To learn how to solder properly ,
visit the "EP resource" on it here

thank you for the reply. that was a brain fart. i have and did use a 6v not sure why i typed that. hopefully your evaluation is different now and this is a "fixable" situation (and a learning situation as well)

i will clean off the splatters but how do i approach that black fried solder on the legend side of the board? it's all very small and wicks and pumps don't seem to get enough and always leave some behind and i'm nervous about putting my 40w soldering pen near such small units on the board.

thank you again for your reply

-Cart

 

[dorke]

Agree, a 40W iron is to much for those delicate SMDs.
Use a 25W, preferably with heat control.

Don't use pumps, they will almost surly lift up pads!

For cleaning solder paste residue use an old toothbrush and clean well with rubbing-alcohol and ear-tips can help as well.

Do watch that "resource" it is great, promise you will learn the art of soldering properly.

 

[Cart]

Agree, a 40W iron is to much for those delicate SMDs.
Use a 25W, preferably with heat control.

Don't use pumps, they are almost surly lift up pads!

For cleaning solder paste residue use an old toothbrush and clean well with rubbing-alcohol and ear-tips can help as well.

Do watch that "resource" it is great, promise you will learn the art of soldering properly.

I cleaned Q2 and C5 and desoldered part of the replacement usb and I think one of the pads are missing, though I don't know what a missing pad looks like relative to a burnt pad.

Any assistance is greatly appreciated.

EDIT: It powers on using the DC properly now. Some progress, now I just need to figure out this usb's missing pad...

 

[dorke]

Not to worry,
It looks like a mounting pad,has no electrical connection.
If the USB socket is firmly held in place there is no problem.
Looks much better

 

[Cart]

Yes, thanks for your help and those PACE vides. Their "Rework and Repair for Electronics" series is just as useful as their "Basic Soldering" lessons.

The USB and DC power it up just fine and the usb won't be moving around anytime soon. Powered on via USB all night with various settings that would inform me if it shut down at all and it went just fine. It is fixed for all intensive purposes, and learned a lot along the way and still have a lot to learn ahead of me. Wish I started this hobby/skill years ago.

These skills will certainly pay for themselves even if I just repair my own gear. One fixed laptop or DC connection and I've saved myself at minimum a $100 repair bill.

Great skills to have during this day and age.

Thanks again.