alesis wedge power supply problem?
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Re: alesis wedge power supply problem?
If you rock the connector gently back & forth, does it become apparent that those solder blobs aren't actually connecting to the PCB?
It looks like either someone has been in there before to reflow them, or that connector was put on the board after the rest of it was soldered.
Notice how all the rest of the solder joints have a little teepee of solder, and it's shiny and smooth, and overall just a little concave? That's that's you're aiming for.
It's blurry, but those look like the textbook definition of a cold solder joint. The solder adhered to the component leg, but not the adjacent portion of the PCB.
Here's a rundown of soldering - you'll see something that looks like your legs in item B:
And a soldering iron for electronics is what you want for this. Maybe 50 Watts, with a tip kinda like a sharp pencil. Not a soldering gun, not a plumbers soldering iron, not a wood-burning kit. Use the shoulder of the tip to melt the blob, then heat the leg and the PCB together until the solder bonds them together. If it has trouble melting/flowing, the tiniest dab of fresh rosin-core solder should get it to melt.
Also, the brown gunk on those legs is leftover rosin/flux from before. You can wash it off with 70% iospropyl.
It looks like either someone has been in there before to reflow them, or that connector was put on the board after the rest of it was soldered.
Notice how all the rest of the solder joints have a little teepee of solder, and it's shiny and smooth, and overall just a little concave? That's that's you're aiming for.
It's blurry, but those look like the textbook definition of a cold solder joint. The solder adhered to the component leg, but not the adjacent portion of the PCB.
Here's a rundown of soldering - you'll see something that looks like your legs in item B:
And a soldering iron for electronics is what you want for this. Maybe 50 Watts, with a tip kinda like a sharp pencil. Not a soldering gun, not a plumbers soldering iron, not a wood-burning kit. Use the shoulder of the tip to melt the blob, then heat the leg and the PCB together until the solder bonds them together. If it has trouble melting/flowing, the tiniest dab of fresh rosin-core solder should get it to melt.
Also, the brown gunk on those legs is leftover rosin/flux from before. You can wash it off with 70% iospropyl.
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- joninc
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Re: alesis wedge power supply problem?
thanks! It's working! still a little finicky so I could probably spend a little more time cleaning up those joints but it powered up right away and that's more than i was getting for the past few weeks !
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Re: alesis wedge power supply problem?
Congratulations!
The connector itself may be a bit worn. But that kind of power connector right on the PCB is one of the very common problems on older cheap gear like that, and easy enough to fix most of the time.
The connector itself may be a bit worn. But that kind of power connector right on the PCB is one of the very common problems on older cheap gear like that, and easy enough to fix most of the time.
- digitaldrummer
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Re: alesis wedge power supply problem?
it also looked to me like maybe one of the pads had come loose from the PCB (specifically the upper left in the picture). Sometimes it's connected to nothing on that side of the board, so if you get lucky enough to make a connection on the other side where the trace is (I'm assuming this is only 2 layer) you are fine. if it continues to be intermittent, you may have to run wire to make the contact permanent.
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Re: alesis wedge power supply problem?
True, and adding a little wire to another pad on the trace is a pretty common repair trick.digitaldrummer wrote: ↑Sat Apr 04, 2020 8:10 amit also looked to me like maybe one of the pads had come loose from the PCB (specifically the upper left in the picture). Sometimes it's connected to nothing on that side of the board, so if you get lucky enough to make a connection on the other side where the trace is (I'm assuming this is only 2 layer) you are fine. if it continues to be intermittent, you may have to run wire to make the contact permanent.
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Re: alesis wedge power supply problem?
could you show me somehow which pad you are referring to?digitaldrummer wrote: ↑Sat Apr 04, 2020 8:10 amit also looked to me like maybe one of the pads had come loose from the PCB (specifically the upper left in the picture). Sometimes it's connected to nothing on that side of the board, so if you get lucky enough to make a connection on the other side where the trace is (I'm assuming this is only 2 layer) you are fine. if it continues to be intermittent, you may have to run wire to make the contact permanent.
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- digitaldrummer
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Re: alesis wedge power supply problem?
I noticed this here:
you may need a magnifying glass to see if the pad is really gone or not
you may need a magnifying glass to see if the pad is really gone or not
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Re: alesis wedge power supply problem?
Or an ohmmeter.digitaldrummer wrote: ↑Sat Apr 04, 2020 5:07 pmI noticed this here:
pad lifted.jpg
you may need a magnifying glass to see if the pad is really gone or not
Sometimes not all the pins are actually used, and so it might not even matter.
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Re: alesis wedge power supply problem?
I have a 20 year old Wedge buried in a box in the garage somewhere. This makes me want to pull it out.
Re: alesis wedge power supply problem?
But what about the Wedge?Flight Feathers wrote: ↑Wed May 06, 2020 4:30 pmI have a 20 year old Wedge buried in a box in the garage somewhere. This makes me want to pull it out.
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