HELP! Damaged MD PCB. Can anyone identify this component?

I was just changing encoders on the MD SPS-1, and to my horror, I saw that I seem to have cut this one component apart next to one of the encoders:


The component is labeled D56 and probably to small for me to fix. But if I can get the component I could possibly get the local electronic workshop to fix this for me…

Anyone know what this component is?

And shouldn’t this be easy to fix?

I don’t dare to turn on the MD in case I might fry something. It’s anyway most likely not working (at least the encoder that this is connected to).

All help highly appreciated. I just got this unit and really hope I haven’t ruined it! :slight_smile:

You haven’t ruined it. Don’t turn it on. That’s a diode of some sort and can likely easily be replaced. It doesn’t look like you did much damage other than to the diode itself.

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Ahhhh great to hear. Thanks for reassuring me :slight_smile:

Say are these kind of components standard, just something that the local electronic workshop should be able to figure out?

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Yep. If in doubt send that photo to elektron and ask for the component ID. Diodes are cheap as chips. I you have are happy to do SM soldering, you could replace it yourself.


Not all shops do smd (surface mount) soldering but most do. Call ahead to make sure.
The diode should be pretty run of the mill but confirm with Elektron for specifics. The part is almost too cheap to charge for, the cost at a shop will be primarily labor/ bench fee.
If you’re okay at soldering this could be a good “level up” project. You’ll want to practice on a different circuit board you don’t care about to get the hang of it. It’s not too difficult but you need to be kinda fast with the iron. Lots of smd tutorials on YouTube.


max 10 seconds on 260* Celsius for SMD
but it’s easy, especially with the soldering pads on the PCB.

how did you break it apart?


Hmm I might just give this a try. :slight_smile: Always good to level up. We’re talking about a mint Machinedrum though… :open_mouth:

When I was removing the encoder with my pliers I must have scraped this in the meantime.

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Just realised that I actually have access to a really proper electronic workshop in my university. Think I’m gonna dive right into the deep end and fix this myself. Wish me luck :crazy_face:


you‘ll do it and never come back.

that feeling when something soldered isn‘t more broken after :1st_place_medal:


good luck! keep us updated on progress. also, welcome to the MD club :slight_smile:

Looks like “maybe” a 4148 SMD diode.
Remember that correct orientation is important (it only works in one direction).

In the picture, the diode “stripe” (Cathode) should be on the left.

Remove the old one by touch the pads one at a time with the soldering iron and lightly wipe the old pieces off by Sliding the soldering iron off the pad gently. Never push hard on anything. Let the heat do the work.

Never leave the soldering iron on the pad for more than 6 seconds. Let the PCB cool down and try again if t doesn’t work.

Next “tin” the pads with fresh solder.

Hold a piece of “leaded” solder (don’t use lead free) on the pad and then touch the pad with the solder iron for just a moment. This should leave a small amount of solder on the pads to prep for the part. Do this to both of the empty pads. You are ready for the new part.

Using some tweezers, set the diode on the pads in the correct orientation.
Hold the diode in place with the tweezers and touch one pad with the soldering iron so that one side of the diode solders to the pad. It should only take 1-2 seconds max with fresh solder on the pad.

Let go of the diode and then touch the other pad with the soldering iron and it should be in place.

If you make a solder bridge on accident, just wipe the soldering iron across the pads gently and it should correct it’self.


If you haven’t done this already here is a vote to get some help. Desoldering is a little trickier than soldering in my view. You also may have to navigate a tough spot there depending on what the back looks like. Good luck either way.

I managed to fix this… with a little help :slight_smile: Scored a diode from another PCB I found laying around, with the same voltage drop as the others (0.6v), worked like a charm. I would not want to have done this operation on my own though for the first time. And we had something like a soldering tweezer for removing the diode, was pretty handy.


Really glad to hear it worked out for you! Also extra points for harvesting from another board! I build/ repair/ modify lots of gear over the years and rarely buy new parts. Our consumer throw away society keeps me well stocked.


Same here. This little pile came out of the WEEE skip at work last week. :slightly_smiling_face:


Good score. Keeping your cost down and diverting from the landfill.
I was just stripping down a bucket full of circuit boards this morning.

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