Behringer DDX3216 - Trying to repair, please help!

[Nisse]

........Also, J7 (AG - DG) isn't present and the screw connecting the heatsink to the board accross the AG and DG rail isn't present? Is this normal? I can't see how it would affect the board and I assume you would want to keep DG and AG separate wherever possible.

Watch this space

Glad my schematics are of use to people.

Hi,
Just what I noticed!!
I have two PSUs.
One older and one "newer" (green and blue board)
On the older, the screw is missing, the jumper J7 is not mounted and the AG is disconnected from DG, but on the newer (which fails on analog power, described above) has the screw mounted, jumper J7 mounted, and the AG is connected to DG! I started to wonder if this could have something to do with my reboot problems... What's right?? Should the AG and DG be connected in the PSU or not?

Regards
Nisse

[gassanov]

Please Reupload DDX3216 schema...i realy2 need it!


thx

[Jazz P Bass]

Download 3216.zip from Sendspace.com - send big files the easy way

[Nisse]

And now, finally, I've managed to repair my PSU to work 100%.
The problem is described in "No power on ANAOUT on ddx3216 PSU" above.
As mention above, it's not just the electrolytics that is bad. Beside some bad solderings, the flat cheramic capacitors is a disaster.
For me, it was the C52 that was the problem, and here is my analys of the situation:
The PC3 works as a voltage regulator to Q3. It gives feedback from the lo-voltage-side to the transformer driver (Q3) on the high-voltage-side.
As mention above, the PSU worked fine (without failure as long as it was on), but when I rebooted it when it was warm, there where no power on the analog outputs. As I can see in the schematics, the C52 works as a "soft power up regulation" to Q3. If the C52 wasn't there, the PC3 would tell the Q3 to go by 100% at startup, because there is no power out yet. This will perform until the right level is achived on the 17V side. This would probably work if the Q3 hadn't have a over-current and over-voltage protection. So that's why we need the C52, to make a more soft startup, while all electrolytics etc. are charged. Now, when I examine my C52, it has a value of 110 nF at 20° C. It's Ok (Should be 100 nF +- 10 or 20%). But when I just warm it up a bit (with my fingers) to about 30-35° C, the value goes down to 75 nF! If I then warm it up to a temerature that I just can hold my fingers to it without burning my self, the value goes down to 40 nF!! So now, the "soft startup" is not enough, so the over-current feature in Q3 is activated, and power the Q3 down. That's why it never will start up as long the power is on, even if I wait for temperature to go down. I need to restart when the temerature is low. This is also the reason why it is working as long as it is on.
So now, to be sure that this won't happen to more places in the PSU, I will replace all the cheramic flat capasitors to multilayer 125° C. capacitors.
One other thing that is really strange is that the elecrolytic capacitors are "high temp 105° C" while the cheramics are not, or am I wrong here?!
Anyway, in my project to repair the PSU, I've also mounted a fan on it, to extend the lifetime on the PSU and the DDX. If any one is interested in that, I will publish some pictures of it, and describe how to do and how it works.

Regards,
Nisse

[gassanov]

Download 3216.zip from Sendspace.com - send big files the easy way

thankyou sooooo much!!

[choe62]

I have a problem with the DDX 3216 is not working any moving fader.


The DDX3216 works in full, stores all the parameters are edited, but does not move the faders and the sound is perfect


When I move the faders manually, the display includes the movement. The memories that I edit, making the actual fader position when stored, but do recall, the display changes to show the position they have at the moment

I've checked visually power supply and shows no swelling or burst capacitor

Tensions are correct as indicated on the circuit board silkscreen

Checking circuit motor control board, I noticed the three IC12, IC15 and IC13 heated in excess, can not have much time because it burns your finger on. These are 74HC595 IC

If you experience with this fault I appreciate your help

Dispose of schematics diagram of the DDX 3216. It also has the technical means for any test.

P.D. excuse my bad English, I'm from Spain

Best regards

[fznuk]

Some great tips on here! - Im waiting until i build the dummy load but may also test the Ceramic Caps as said above. I think, in the end is to monitor all voltages under load since we do know that the IC's on the main boards dont like unstable voltages but would be great if someone could post up what would be acceptable voltages we can have from a fully working PSU?!

Its a real shame Behringer didnt come up with a better PSU or a 'fix' as this desk is still one of the best budget digital mixers out there

I personally dont really need a mixer anymore now i use a Safire Pro40 1U soundcard connected to a Behringer ADA8000 8 channel expander.......and now the studio is quiet once again! lol - But i still would like to fix my mates DDX since even though he has the same setup as me, he would like it for his drums.

If i actually get to build the dummy load and succeed in fixing the PSU I will post my finding but please also keep up your own findings and fixes.... Photo's also please!

Cheers again guys!

[choe62]

Finally I managed to solve the fault

It was the ICs 15, 12 and 13 (74HC595), and several MOS FET transistors NDS7002 used to enable / disable the signal passing the ICs LM324 that activate the motor

With the help of schematics diagram of the multimeter and a good dose of patience I have located these defective components.

I gather that this failure was caused by instability in the power supply, as both ICs and MOS FET transistors, were in shortcut

[hspilot0000]

Thank you so much guys! and from a thread i read on here regarding this mixer, it was you guys i was hoping would reply

You are right in not throwing random components at it which is why i only replaced output filter caps which i read from a thread on another forum, but with this not making any difference, together with pulling and replacing connectors, i decided to ask on here since your other replies on posts sounded like you guys knew this unit well.

Im pretty competent with understanding electronics and with a bit of a brush up on circuits like switch mode power supplies im sure i can get my head around it but my main job is PC diagnostics so i don't come across too many component level repairs these days.

I have a purpose built electronics workshop but my test gear is limited to an old Scope and multimeter.....then usual tool...and soldering iron. But the desk is pretty big so decided to open and fix on the kitchen table!



I originally noted down all the caps on the PSU - i also noticed that its built up from three PSU's with various voltages. I was going to get all the caps but decided to try the output ones first, i will see if i have a spare 47uF to try!

You also mention the crystals - are these Q1 & Q2 on the processor board?

Thanks again for your help!

I will keep you all up to date on if i fix it or not

Hi fznuk,

A bit off your topic but I need to replace the fan on a DDX3216 but would like to buy it before I go and fetch it from the client. Could I ask if you can give me the specs (size/voltage) of the cooling fan?

H

[Jazz P Bass]

As far as I know the fan is 12 Vdc.
0.12 A
80 mm square.
Like on a PC power supply.

[hspilot0000]

As far as I know the fan is 12 Vdc.
0.12 A
80 mm square.
Like on a PC power supply.

Thanks

[fznuk]

Behringer Fan

er... No the Fan isnt 80mm, its tiny (as shown in my pick of the bottom half of the case...right hand side, half way up and near the back) - and i dont think its 12V, i think it may be 5V.....but will have to have a look once I get the desk out again.

[JUAN]

Big problem with my ddx3216

I have a behringer ddx3216 i was using it fine, i just powered it off and came back to power it on and it froze, it just stays on the initial screen where it says "ddx3216" i tried pressing ch1-16 and setup and nothing, i tried turning it on and off several times and nothin, it just stays on the initial screen, what possibly could it be?

[r007]

I have uploaded the complete schematics for the DDX3216 (including the PSU) as a zip file onto the following url for anyone to download if they wish

Awesome, thank you so much!

Well, I'm having a bit of trouble with my 3216 as well. After a bit of running, all input channels start showing some intermittent signal. The meter bars go up to -36, and if I turn the volume way up, it sounds like a "fp".
After a bit of looking at the ANAIN schematic I'd think that one of the 17V lines is at fault. (My reasoning being: since the signal LEDs in the preamp section light up as well, and the only common power source to all channels are the 17V rails and VCC/VDD, but no digital component flukes out, so VCC/VDD should be OK.)

So I should probably be looking at the power supply, right? My google-fu seems to be weak, I've only found one other reference of this problem, and their PSU broke down shortly afterwards... Any of you repairpeople heard something similar?

[zeubest]

Yes, Great tips here indeed !!!