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Not So Happy Ending For Simple Fix That I Complicated

Discussion in 'Pioneer Audio' started by zenarrrow, May 14, 2018.

  1. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    I started a thread about my SX 980 not having indicator lights did some diagnosing with the help of some very good members here. The only Indicator light that worked was the Stereo Indicator which runs off another power supply than the others.
    Instead of just fixing a bad resistor I decided that a complete recap of the Power Supply board to be in order since I was already this far into the rig.

    Feeling confident about everything I ordered the parts for the PS board AWR-156. Got them in the mail and jumped in. Everything was going well I did all the Electrolytic capacitors first, after doing those all day yesterday, I tested the unit and everything was working just fine. They I knew would be the easy part.

    Today I started with the Transistors with Q5 in particular, I struggled with getting this out but finally got it out and put the new part in place. I took pictures of everything before I started each separate component on the PS board. Everything I took out I took pictures and wrote how they were put in, and placed the new replacement parts in exactly as I took them out.

    Finally got done after a while I powered up the unit, I have no sound. I get the power lamps across the top all three work. Now when I tune to a FM station the Stereo Indicator is very dim still lights up and I can see the tuning meter moving when dialed into a station. I tried also the AUX with my CD player again nothing, no noise static anything from either AM/FM or AUX

    I am pretty sure I had to have damaged the the Power supply board AWR-156, especially starting with Q5. As I feel I kinda roasted the board trying to remove the transistor. I did learn after that how better to remove them, but maybe too late.
    I grabbed my multimeter and as I was walking across the room the positive lead fell off of my cheap DMM. No way to get inside and rewire it. I was able though, to just use the ends of the wires of the pos lead and the neg lead, take out all my fuses and check the ohms. All the fuses are good.

    So it seems I am dead in the water until I am able to find another AWR-156 Power supply board to drop in. Hopefully nothing else is toasted. Just strange that the Stereo light is a lot dimmer now.

    Just curious if anyone may have any ideas that I may be over looking ? Or if anyone has a PS board for the SX 980 laying around that they would like to sell.
    Thanks, Joe
     

     

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  2. captouch

    captouch AK Subscriber Subscriber

    Messages:
    4,471
    Location:
    Bay Area, CA
    Did you put the new transistor in with the right leads going to the right places? You can't just judge by having the shape orientation of old and new be the same as the B C E aren't necessarily in the same places on the package.
     
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  3. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    I think that is where I went astray..... I have on order another set of PS caps and transistors, diodes etc. I am not too proud to say I just placed them as I saw them in the line, as I took them out I noted the position.
    Do you think I have caused any damage?
    If I do not power it up any more and place them in the proper spots when they arrive? I will read and research how to do it correctly.
     
  4. john stumpf

    john stumpf AK Subscriber Subscriber

    Messages:
    646
    Location:
    philippines
    some lessons are best remembered through screw ups!!! all is not lost! pinout CANT be overstressed. look up EVERY part and get the data sheet and check the pinouts on every part you put in for starters. do you know how to interpret the transistor symbol silk screened on the board?
     
    zenarrrow likes this.
  5. Watthour

    Watthour Electron Rancher - JS3600

    The MJE15032 pinout is B-C-E, just like the 2SD712. The positions on the PS board which need to be altered are Q 2 & Q3. The replacement devices are oriented differently. The originals are B-C-E while the replacements are E-C-B. There is a chance that no other damage was done to the circuit, so installing transistors in the proper orientation in those positions may resolve the problem.

    You will need to use a clean, well-tinned iron with sufficient heat to do the joint in 2-3 seconds. Any more than that can result in component damage or damage to the board or foil traces. If it takes longer, the iron may not be hot enough, may not be clean enough, or the solder may be the wrong alloy for the job.
     
    Bill Ferris, zenarrrow and captouch like this.
  6. 1MEGΩ

    1MEGΩ Active Member

    Messages:
    209
    Location:
    Mamou, Louisiana
    What I would like to know is why you replaced Q5 if everything was working good? Makes no sense to me.
     
    Watthour likes this.

     

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  7. rcs16

    rcs16 Super Member

    Messages:
    3,887
    Location:
    Baldwin, Ontario, Canada
    It seems to me the thinking by many around here is because, "Joe" in the other thread advocated changing it, so must I. Monkey see, monkey do.
    I myself and some others, believe that in many cases, cooling the device better than the factory did, buys you more reliability, which is the end goal of this exercise.
    I was taught that, every 10 degrees C you drop the Si junction op temp, doubles the life of the device.
     
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  8. captouch

    captouch AK Subscriber Subscriber

    Messages:
    4,471
    Location:
    Bay Area, CA
    If you have a dim bulb tester, I would correct the orientation of the transistors and try it with the DBT. You may be okay.

    If the DBT glows really bright or you still get no sound, them you'll have to troubleshoot to see what's damaged.
     
    zenarrrow likes this.
  9. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    Please see post #7 in this thread. Sums it up perfectly.

    Just a Coincidence that my name is Joe
     
  10. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    I am going to take a look at this on Thursday morning after my graveyard shifts. 12 hour shifts from 6pm to 6am. Hopefully everything is fine.
     
  11. 1MEGΩ

    1MEGΩ Active Member

    Messages:
    209
    Location:
    Mamou, Louisiana
    Well Joe, here's some advice. If it's not broken, then don't fix it!
     
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  12. zebulon1

    zebulon1 Getting behind on work. I need help? Subscriber

    Messages:
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    Location:
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    Why not use your negative energy and help the guy out of a jam. Lesson learned the hard way.
    This forum is for helping not criticizing.
     
  13. captouch

    captouch AK Subscriber Subscriber

    Messages:
    4,471
    Location:
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    +1

    QFT
     
  14. 1MEGΩ

    1MEGΩ Active Member

    Messages:
    209
    Location:
    Mamou, Louisiana
    I don't see giving someone good advice as negative energy. I do help people here.
     
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  15. Watthour

    Watthour Electron Rancher - JS3600

    Focus, gentlemen. We all know that everyone contributes whatever we can.

    Zenarrow made a couple mistakes (which we've ALL probably made at some point) so let's continue to help him out of his situation. I think we're really close to the solution, so long as Zen gets a little sleep before diving back into the project.
     
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  16. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    +1
     

     

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  17. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    I am truly amazed at the support and understanding with the issue I have. Cannot express enough how thankful I am that you guys are there to help me with my self admitted mistake. Also the patient in waiting for me to finish my work week. This site and the folks here are beyond description. Thank again.
     
    captouch likes this.
  18. loweran

    loweran AK Subscriber Subscriber

    Messages:
    1,009
    Location:
    Austin, Texas
    BTDT. I learned to use mini grabbers and power down when switching them on the posts. Takes longer, but not longer than having to go back and test and correct blown parts. I was able to correct mine and didn't blow the outputs. All you need is time and patience and it will pay off.
     
  19. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    So, I took Q2 and Q3 and put them in the correct way. If you recall I stated the STEREO indicator before was rather dim. It once again is bright as it should be. But still no output via AM/FM or AUX. Might anyone have any idea of what else I may have put it in wrong?
     
  20. zenarrrow

    zenarrrow AK Subscriber Subscriber

    Messages:
    740
    Location:
    Wyoming USA
    It tunes in and the tuning meters are active. Same with the AM. Does anyone know what part sends the power to the out puts?
     

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