# anyone with circuit board experience care to offer their opinion?



## 10409 (Dec 11, 2011)

i'm having an issue with a digital interface. it was working, then it fell behind my desk, now it won't power on.

i took it apart, and there's a very suspicious piece where the phantom power input is










is it a safe bet that this piece is the problem? any chance it would it be as simple as soldering it back together, or would i need to acquire a new part?

it's a line 6 ux2 studio pod. i tried to find a healthy circuit board to compare but couldn't find a picture of one.


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## mhammer (Nov 30, 2007)

I'd probably need to see more of the board, but the critical information here is the fact that the fractured piece is labelled L1. L stands for inductor in most component legending schemes. Inductors are used to smooth power or prevent various sorts of noise from coming over the power lines. You may have heard people speak about "chokes" in tube amplifiers? This is the exact same thing, only smaller. Unfortunately, when used in this manner, they are placed in series with the power source. Not _always_, but often enough to consider it in this instance. 

What that would imply is that unless you can figure out what the value of L1 is in this case (and perhaps Line 6 would be happy to provide you that info if it meant not having to repair it themselves), and install a suitable replacement, you may be stuck. The good news is that you *CAN* refer to it as L1, rather than simply "that sort of black thing near the jack", and they'll know what you mean. 

The other good news is that the piece is not terribly small. Player99 brought over his Variax a few autumns back, and we momentarily lost track of a resistor on the board. That sucker was about the size of a sesame seed. This inductor is at least somethng a normal person can hold between their fingertips without having to use dissecting tweezers.

If you can find out that info, bring it by and I'll be happy to install it for you....assuming a reasonably warm day, because jeez louise that garage bench is cold!


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## 10409 (Dec 11, 2011)

appreciate the quick reply, mark, thank you!

i'll open a support ticket with line 6 and hopefully they give me the info i need
it's no big rush...just something that i've been meaning to look into for a while and there's no better time to tinker around indoors than when it's -36 outside!


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## 10409 (Dec 11, 2011)

In case this helps...


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## nonreverb (Sep 19, 2006)

There's a junked Line6 amp at Steve's. I'll take a look today.


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## 10409 (Dec 11, 2011)

awesome, thank you

After having a trained eye look at it, we (ok...he) determined that the casing around the J1 input was pushed back when it fell, which pushed the L1 piece out of the way. makes sense. I pushed the J1 casing back into position and the broken piece became much more flexible, so i removed it. pretty clean break, but you can see two little wires inside the piece itself that i'm guessing wouldn't connect properly if just shoved back together.










I made an inquiry with line 6 tech support, no response yet. said within 3 business days.


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## Wild Bill (May 3, 2006)

You realize that L1 only means something to the manufacturer? It means it is the first inductor on their parts list. It says nothing about the actual inductance value or even the type of inductor!

It's like someone going to a music store and asking for a new string for his guitar. When the clerk says "E string? A string?" the customer says "They're different?"

So you will probably have to get the part from the manufacturer, unless you can find a schematic that also gives the actual spec of L1.

Even if you get the spec, you will then have to find a store that carries such a part and will sell to you in small quantities.

Welcome to the fun world of fixing stuff!

Wild Bill/Busen Amps
?


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## deadear (Nov 24, 2011)

She's a Scrap.


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## jb welder (Sep 14, 2010)

Don't sweat it Mike, if they will tell you the value of the inductor it should be a cheap fix. Those parts are cheap, it is basically a tiny coil of wire usually used for suppression of RF. I'm guessing the unit might work with just a piece of wire across there. But you might have interference issues or if that jack is for digital signal it might not work right.
What is the model # of the interface unit?


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## 10409 (Dec 11, 2011)

it's a line 6 ux2

it had been mentioned that just bridging the gap with a piece of wire will turn it on but leave it more prone to signal interference from wireless devices, and it might be a last resort but there are way too many devices that would interfere with it in close proximity to where i have it set up...to the point where if it could be a problem it surely will.

line 6 got back to me and said they have no access to that kind of information, however they are going to see if they can get me approved to receive a refurbished one under "warranty"

fingers crossed


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## jb welder (Sep 14, 2010)

Let us know the outcome of this. Whoever you dealt with at Line6 must not realize they actually have schematics for these things. I'll try to find out what the value of that coil is. Then it sounds like Mark could replace it for you.


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## nonreverb (Sep 19, 2006)

Agreed. You might be able to sub one in and presto. Look at it this way, right now it's worthless so what's the risk?
P.S. still looking for that board 



jb welder said:


> Don't sweat it Mike, if they will tell you the value of the inductor it should be a cheap fix. Those parts are cheap, it is basically a tiny coil of wire usually used for suppression of RF. I'm guessing the unit might work with just a piece of wire across there. But you might have interference issues or if that jack is for digital signal it might not work right.
> What is the model # of the interface unit?


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## mhammer (Nov 30, 2007)

jb welder said:


> Don't sweat it Mike, if they will tell you the value of the inductor it should be a cheap fix. Those parts are cheap, it is basically a tiny coil of wire usually used for suppression of RF. _I'm guessing the unit might work with just a piece of wire across there_. But you might have interference issues or if that jack is for digital signal it might not work right.
> What is the model # of the interface unit?


I was just having that same thought. There is a strong possibility it would not work _as quietly_, but it would likely "work" unti such time as the appropriate replacement part was identified, sourced, and installed.


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## jb welder (Sep 14, 2010)

So it is like a ferrite bead, not really an inductor. The part number is HH-1M3216-501.
Parameters are: |Z| = 500Ω @ 100MHz, RDC = 60mΩ, rated current = 3A.
Mark, would you be able to source an equivalent?


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## 10409 (Dec 11, 2011)

i'm not sure how you were able to find all that, but thank you! could anyone recommend a parts source?


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## mhammer (Nov 30, 2007)

The manufactuer is CTC ceratech. I'm looking for a known commercial distributor in Canada. So far, it seems the likely suspects (Mouser, Digikey) don't carry it, although this one from Murata (which Mouser does carry) seems like a pretty good match.

http://ca.mouser.com/ProductDetail/...=sGAEpiMZZMsVJzu5wKIZCYmZU4bx33JYLQXdnqirj9E=

And this one by Bourns, at Digikey, seems like an even better match: http://www.digikey.ca/product-detail/en/MH3261-501Y/MH3261-501YCT-ND/3925579


Oh, and how the hell DID you find out that's the part number?


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## 10409 (Dec 11, 2011)

silly paying 8$ shipping for a 17 cent piece. how about you make a list of things you could use or could one day use and i'll add it to the cart as a thank you for helping me install the piece.


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## jb welder (Sep 14, 2010)

mhammer said:


> Oh, and how the hell DID you find out that's the part number?


I asked the good doctor at the MEF :smile-new: .


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## deadear (Nov 24, 2011)

I had good luck getting discontinued IC chips for a Marshall on E bay. All these electronic distributors in North America were selling subed parts and the shipping would have been the same price as the original discontinued parts I got from Hong Kong. Had them in my hand in week.


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## Stonehead (Nov 12, 2013)

You could give these guys a shot. They've sourced some hard to get components for me in the past.

http://www.be-electronics.com


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## jb welder (Sep 14, 2010)

This is not an IC, just a ferrite bead, so no need to get the exact original part, just the right value. Pretty generic, like capacitors or resistors, no need to match up the original brand.



deadear said:


> All these electronic distributors in North America were selling subed parts and the shipping would have been the same price as the original discontinued parts I got from Hong Kong.


Be extremely cautious buying new "obsolete" components from China, the counterfeit industry for obsolete semi-conductors is huge! Why would all these stockpiles of new obsolete parts be showing up in China? Parts that were for products that were never built or assembled in China. They are often similar parts re-labelled as obsolete parts, but often of inferior quality or just plain fake. Like fake power transistors that blow up when turned on.


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## deadear (Nov 24, 2011)

good point jb. But I will support other economy's like 99% of the people in this country.


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## beta_raybill (10 mo ago)

Hey man! Years later, I have the same problem. The L1 and C29 components broke because of the USB B (J1). Do you know which components are those? Or have any schematic of the UX2?


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