Trying to track down power supply: Sony LMD-4420


I bought a cute little rack-mounted 4-screen LCD monitor off of ebay. You can see what one looks like (not mine for reasons that will soon be clear) here In my excitement, I made the classic mistake of not confirming that it came with the power supply; spoiler alert–it didn’t.

So now, I find myself hoping that someone on here might have ideas of how to find a compatible adapter. Here’s what I have figured out so far:
-The jack is for a barrel-type plug,
-It measures 4mm wide, not sure how deep,
-the right plug would have a pin in the center, kind of like a laptop charger.
-It’s marked as 12V DC center positive.
-A photo from another eBay listing shows a power supply that is also like a laptop charger in that the plug goes to a box, and that box would then connect to another cable that goes to the wall. (as in, not the typical “wall-wart” ac adapter)

I have a “universal” AC adapter I use for my AVE-MOD, but all of the barrels that come with it are too small and don’t have pins in the middle. Looking at “universal” laptop chargers online, they all seem to be 18V and up, and of course it’s hard to know if a particular tip will fit without seeing it IRL.

Thanks for reading this far!


Those things are a pain. There are a few different sizes and they aren’t that popular so most universal adapters ignore them. Worst case scenario, jsut buy any old 12v adapter that can supply enough current (most decent switch mode supplies should be at least 1-2 amps and that’s probably enough), measure the inner diameter of the jack on your Sony, and then but the right plug and replace whatever your adapter came with.

I bet this is the type you need (but this specific one isn’t necessarily the greatest quality, and check the center pin diameter if you can!):

This seems lik a good trick, and also I’m sure a Dgikey rep could help you out

Since the pandemic messed up the supply chain I’ve hadmuch better luck with Digikey (and even Tayda) than with Mouser, in terms of lead time, availability and customer support. I’ve still got a few parts from a few April, 2021 orders that are backordered until summer 2023 on Mouser but was able to get them all easily on Tayda and Digikey.

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Thanks for these tips! This is super helpful. :smiley:

maybe as a first step you could find what exactly the connector is in the user manual or in the service manual, sometimes there’s a list of components there

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The service manual!! Such a good idea, the regular manual just listed the type of plug on the part that connected the AC adapter box to the wall plug/mains (just a generic power cable of the sort that would plug into say a desktop computer), but the service manual had a part number for the AC adapter part that led me to an affordable one I could order from the hopefully-legit :crossed_fingers: it’s the right one, will update when it arrives. Thanks!!

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