# My DIY DLS rca repair thread



## [email protected] (Jun 12, 2008)

I have a DLS A6 I bought form the forum here that needs some work done. SO this thread will show what work is gonna be done and the work being done. 


I will have acouple questions along the way. I am in no way, in any shape or form, a expert at any of this. I can follow traces (mostly), read the values of parts, and with my new solder gun  solder pretty well. De-soldering with big parts still on it seems difficult, I guess the part is absorbing alot of my heat, so it takes longer to do.


So first up the section that need to be fixed. This amp came to me knowing it had a RCA issue. I was told the output would cut in and out. I assume I knew what the problem is. I for one do not like how rca's mount to the main board. I have seen alot of problems from people pulling rca's off and doing it at an angle, creating alot of stress on the solder joint, which in turn can crack the solder or rip the via pad out.

This amp was repaired by someone besides me previously for the same reason. In this attempt the board was burnt and the pad was ripped. The traces were also burnt running to some SMD resistors.

So here are some pics of the burnt board and missing via's, I need to snap acouple more of the top. 


To start the repair I am waiting on DLS to get me the schematics of the pre-amp section, I can do it without, but would be easier with it, so hope fully Gunnar emails it to me shortly.


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## [email protected] (Jun 12, 2008)

In the last picture you can see a pad ripped out, it was like that, but it was connect with just solder. I will replace the trace. It is right in front of the burnt part.


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## [email protected] (Jun 12, 2008)

I should have noted this will prob move kinda slow, as ordered 5 pairs of tiffany style rca's from hong-kong  Same as the dayton audio ones which partsexpress wants $7 a pair 


Anyways I fixed the trace last night. So here are some pics of the procedure I used.



Step 1 - Sand down the resin/epoxy that is over the traces (might be kinda hard to see as all my pics are taken with my iphone) The traces there are alittle shinnier than the others











Step 2 - Put down acouple beads of solder at the contact points










Step 3 - Lay the de-soldering wick over the points (I dont have a pic of that just laying there

Step 4 - Melt the solder under the de-soldering wick, I then proceeded to add alittle to the top above those contact point so I knew it was thoroughly distributed all the way thru the de-soldering wick.












So there we have my finished product of the trace, it looks worse in the pic. It does not add abounch of bulk to it or anything, just kinda looks like it. I am happy with how it came out. I tested the resistance of the trace to make sure it was ok, and everything was just fine. 

So now I need to order my new resistors and get those put back in and get the circuit complete. Then all I will have to do is connect my RCA jacks to the wire I will put inside.


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## [email protected] (Jun 12, 2008)

So instead of replacing the SMD resistor with another SMD, since they are super hard to solder. I am replacing with a metal film resistor of equal value and power handling, the new ones will have a .1% tolerance. Not sure if that is really needed over a 1% but they have them so why not


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## [email protected] (Jun 12, 2008)

So here we have a pic of the top side of the board. 










You can see what I am workin with here, pretty bad shape, but easily fixable.

You can see I am missing RP509 which is a Surface mount resistor. Thats easy enough to figure out since the other side is the exact same. I just need the value of RP504. Its a 1k ohm resistor, 1 watt. 

You can also see the purple surface mount cap by the missing resistor. You can see the trace is missing part of it since the pad for the positive rca was ripped out. I will have to tap into the trace there.

Here is a pic with a flash light under the board so you can see the traces better.











Thats about all I have today. I am still waiting for a response from DLS, which I am surprised I have not received yet. I need to get a value of a part, I have no clue what kind of part it is tho. Its labeled CX4, its between the L/R rca spots on the board, its is used for a ground, I can tell that. But whatever CX stands for I have no clue. I dont think its a cap as all the other caps are labeled CPxxx, x's being the location number


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## [email protected] (Jun 12, 2008)

I would like to take a second and thank Eric (Dr. Fosgate) for always answering my questions I have about circuits. Because of him I have a better understanding of these things than I did before. I have learned alot form talking to him and reading some of his tutorials and reviews.


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## [email protected] (Jun 12, 2008)

Made some progress on it. I am at the point where I just need my rca sockets to come in and I can finish it. I have all the resistors and caps that were needed installed and wired.


Here you can see the wima cap I installed to replace one that was missing. It grounds the rca jacks to the sink. Then you can see the resistor that I used for the one that was missing. I see now why they use surface mount ones nowadays, so much smaller. 









And then here you can see the wires I will be using to connect the rca sockets. I need to clean some of the globs of solder up off the traces and I am gonna put some heat shrink on the resistor/wire connection. Finally trim up the wires and connect them to the sockets, then I am ready to test it out. 











Its not pretty, I knew whatever repair was gonna be done to it wasnt gonna be when I first opened the amp up. I am kinda happy with the turnout so far. Everything is solidly connected, and the paths are complete again.


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## [email protected] (Jun 12, 2008)

I would like to add DLS has been more than helpful also. Per sent me the schematics I needed. My email has been buggy lately so they were being bounced back to him, thats why it took alittle longer than expected to get them. DLS customer service is top notch. I have not found better at any company I have dealt with, and I have dealt with alot, ever!! I lost one of my tweeter grills to my UR5s component set, and they sent me one for free from Sweden, they even paid for shipping. Not many companies will provide the schematics for their amps either. So thanks to all at DLS that have helped me with this and helped in the past. Big thumbs up!!!!


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## Aaron'z 2.5RS/WRX (Oct 24, 2007)

Looks pretty good man... 

Couple of things, if I may.. 

Consider bridging the traces you repaired with some fine copper wire.. If enough current ran through it to fry the copper, the solder isn't going to hold should it get "warm" again.. the copper will take the bulk of the load.. 

If you aren't using it, go buy a bottle of liquid flux, it's worth it's weight in gold..

Use acetone or alcohol to clean after.. 

What sort/size tip are you using on your iron? 

I can't quite see how that resistor is soldered down, but if you tried just soldering it to the SMD pads on either side, it's not going to hold, unless you blob on some hot glue to support the resistor.. 



Cheers..!!


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## [email protected] (Jun 12, 2008)

^ Thanks.

As far as the traces. There was only 2 I needed to repair. The one that goes from the positive pole of the RCA to that resistor, and one for the ground on the board for the negative rca wire, on the bottom of the board. The negative RCA wire one was the one I repaired with de-soldering wick, which is basically flat copper wire. 

The solder I am using has the flux in the core of it so there is no need for any extra flux. I have not wipe any of the flux up yet. I do normally use rubbing alcohol. I need to get some more 90% stuff as anything below that leaves alot of streaks on the board.

The resistor is kinda "ghetto" if you would. So one lead of the resistor that is sticking up, then bending back down. That is soldered to a small pad by where the surface mount resistor went, this pad is on the center of the trace next to the resistor pad. I then drilled a small hole for the other lead of the resistor that sits down on the board. I took that lead and pushed it through the hole, I then routed that lead back up where the positive pole for the rca mounted, the hole where the pad was burnt/pulled out. With this weaving action, it was pretty sturdy. I did then put a small amount of hot glue on both sides of the board under all 3 spots. I am not going to tell you that it is as sturdy as a thru-hole mount, but I can push it pretty hard and it does not budge.

I am actually gonna redo the wires I have there for the rca connections. I test fited a pair of rca sockets from one of my old PG amps and those wires do not need to be so long, they are super stiff also, which I dont like.

Anyways thanks for looking and having acouple suggestions. If you have any more dont hesitate to say something. Others might have a different process that might come in handy. Im just kinda winging it anyways


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