SX-1010 AM I GETTING CLOSE??

Discussion in 'Pioneer Audio' started by TigMan, Jan 18, 2019.

  1. TigMan

    TigMan New Member

    Messages:
    39
    Hey all, I started by having a rig that was blowing two fuses on the power supply board when powered on. I changed C8, C9, and D1-D4, R12,R15,R21. That made fuses stop blowing, but now I have panel lights only on the dim setting, and it also made my tuning needle jump to a specific location when clicked to AM or FM. No relays click, no static or noise when running.
    Since then, I went ahead and recapped the rest of the power supply board. Testing all pins 1-15...
    1= 16.8mV
    2= 18.3mV
    3= -66mV
    4= -52mV
    5= -16mV
    6= 4.46V
    7= 0
    8= 12.58V
    9= -11.32V
    10= -49.8V
    11= -20.8V
    12= 0
    13= 31.18V
    14= 49.4V
    15= 22.46V
    They seem legit as far as I could tell. I flipped it over and started to tool around a bit and noticed only two things that made me go hmm. Pin 12 on the protection board (AWM 062) appears to WANT 7.5V on AC unless I'm mistaken?? I am reading 0.13V on AC.
    Otherwise, the power amp board (032C) I read only 35V on pins 8&9 as they appear to want 50V. Not sure that's within tolerance. This is all running under a Dim bulb tester, and im very new at all this. Please tell me im onto something. Any ideas??! Thanks ahead of time.
     

     

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  2. zebulon1

    zebulon1 Building a new bench. Finally! Subscriber

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    The 7.5vAC comes from fuse 1 on the fuse board AWR-053 it also runs the panel lamps in bright.
    The power supply voltages are reading correctly. Good job.
    What is the DC voltage at the big filters? They are part of the unregulated circuit that powers the outputs at pins 9 and 11 of the amp boards AWH-032.
    I suspect a bad bulk (Big) filter cap. The 18000uf/63v ones.
    Read and report the protection board pin voltages.
     
  3. TigMan

    TigMan New Member

    Messages:
    39
    Okay, the big caps:
    Closest to the wall: -.3mV/-34.68V
    Closest to center: .1mV/34.7V
    Protection Board (062)
    1= 12.3V
    2= -11.6V
    3= .002V * AC
    4= 0
    5= 10.4mV
    6= 10.2mV
    7= .002V * AC
    8= -7.7mV
    9= 31.86V
    10= 31.88V
    11= 31.88V
    12= .13V * AC
    I just assumed AC on these because DC was all over the place. Is that generally safe to assume?
     
  4. onwardjames

    onwardjames Hoardimus Maximus Subscriber

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    TigMan, listen to Zeb. He's the Zen master of 1010's. Mine I bought from him is on now, with its wonderful warm blue glow, and that soft, but magnificent sound.

    Truly a home run for Pioneer, the first volley in the "watt wars".
     
  5. TigMan

    TigMan New Member

    Messages:
    39
    I can live with that. I'll take the best help I can get. I typically have the opposite effect on electronics, but i sure do try. I've got a pair of cerwin vegas in the garage that is itching for some juice. And i certainly appreciate all your guys' help getting me to that point.
    Zebulon, I should add, somebody has been in here before. All the major guts appear to be here the best I can tell, but there are a few transistors on the projection board that have been snipped and butt joint soldered with new transistors. I haven't gone as far as to cross reference numbers yet, don't know if we're beyond that at this point.
     
  6. larryderouin

    larryderouin Turn it UP, POP? PLLUUEEEZZZZZEE Subscriber

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    The MASTERS for the 1010 on here are in no particular order, Mark the Fixer, Zebulon1, and MATTSD. I should add Echowars, but he hasn't been posting much on here lately. Listen to what they say, do what they ask when troubleshooting, and don't get ahead of them and ASSUME anything. ASK QUESTIONS till you're blue in the face.
     

     

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  7. TigMan

    TigMan New Member

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    I guess i'm a little curious if i'm doing this correctly? I've never tried online forums before. But all I've done thus far is type in the reply box and hit post. Does it then send a notification to anybody who has been involved in this thread, and open to anyone else who has input?
    I haven't dug into much else, just lifting a couple boards looking to see if I find burnt spots or anything, and looking around with the voltmeter a bit.
     
  8. TigMan

    TigMan New Member

    Messages:
    39
    Another broken part/question? The Base mount for bar antenna holder plastic shroud is broken. I found a fella selling the shroud on ebay for$25 or the whole assembly for$50. Question being, the only extra part missing from my assembly is the little dish shaped spacer between the spring and ball joint... Is that plastic? Or metal(conductive)? Can I just get a washer for the ball joint to rest in? Or should I just cough up the cash and get the assembly?
     
  9. zebulon1

    zebulon1 Building a new bench. Finally! Subscriber

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    A washer of the same size will work. Maybe a tiny bit of grease to ease the movement.
    Only if you quote the poster will there be some notification. Other than that the members will notice a bold thread title indicating a new post has been made since the last view.
    Oh and:
    Where are the voltage reports I asked for? :dunno:
     
    Last edited: Jan 19, 2019
  10. TigMan

    TigMan New Member

    Messages:
    39
     
  11. TigMan

    TigMan New Member

    Messages:
    39
    Golly I suck at this...
    Okay, the big caps:
    Closest to the wall: -.3mV/-34.68V
    Closest to center: .1mV/34.7V
    Protection Board (062)
    1= 12.3V
    2= -11.6V
    3= .002V * AC
    4= 0
    5= 10.4mV
    6= 10.2mV
    7= .002V * AC
    8= -7.7mV
    9= 31.86V
    10= 31.88V
    11= 31.88V
    12= .13V * AC
    I just assumed AC on these because DC was allover the place. Is that generally safe to assume?
     

     

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  12. zebulon1

    zebulon1 Building a new bench. Finally! Subscriber

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    I suck it it.
    I missed the readings, sorry.
    The left amp board has an issue. Pin 1 of the protection is indicating 12 volts means the amp is out of balance. Double check the reading. Pins 1 (left amp) and 2 (Right amp) of the protection AWM-062 should be in the millivolt range.
    The big caps are reading correctly.
    Can you post an image of at least on amp board?
     
  13. TigMan

    TigMan New Member

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    39
    15480058529076531419849280895379.jpg
     
  14. TigMan

    TigMan New Member

    Messages:
    39
    Okay, I must have been sniffing glue or something changed. All my other readings are the same as before, but PIN 1 is actually reading 8mV now with the dim lights on. Closer to 9mV with lights off. Pin 2 is in fact still reading NEGATIVE 11.6V
     
  15. TigMan

    TigMan New Member

    Messages:
    39
    Finding a much more reliable ground my so called "AC" readings:
    Pin 3= -.2mV
    Pin7= 7mV
    Pin12= .39V
    Everything has been double checked. Sorry for stupid mistakes. I can redo that picture if you need also.
     
  16. TigMan

    TigMan New Member

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  17. tsd71

    tsd71 RIP Tom Petty

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    Do I see a TO-220 transistor on the board below the amp (protection board)
     
  18. TigMan

    TigMan New Member

    Messages:
    39
    Here is a closet look at the protection board. And yea there are 3 transistors here that have the snip then splice thing done...
     

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  19. zebulon1

    zebulon1 Building a new bench. Finally! Subscriber

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    As "tsd71" and the rest of us have seen in the images, the receiver has been mucked with. Probably both amps and as you have seen, the protection board.

    The millivolt readings can be read in several different ways.
    .001v is = 1mV
    .023v is = 23mV
    1mV = 1 millivolt
    The point (.) included in the same readings in mV can throw us off.

    The only AC reading on the protection board is the 7.5vAC on pin 12.
    A good ground for all the AC and DC readings is the chassis, any good clean unpainted metal.
    With this new knowledge, could you retake the protection reading?

    The DBT is dim when operating the set? It should be a faint glow when operating on a 100 watt bulb in good operating condition.
    Do you hear the protection relay engaging on powering up?

    Your doing a good job sorting this receiver out. Don't get discouraged in the time its taking to cipher through it. Your catching on quickly.
    The time spent now will bring back rewards.
    Even still, by the looks of it, your going to have to dive deep into this crusty receiver to bring it back to life.
     
    Last edited: Jan 20, 2019
    onwardjames and merlynski like this.
  20. TigMan

    TigMan New Member

    Messages:
    39
    Okay, here are my fresh readings. I got a good ground and went through a couple times. Protection board #062...
    1 = 7.6mV
    2 = -11.6V
    3 = -0.4mV
    4 = 0
    5 = 7.9mV
    6 = 7.9mV
    7 = 7.5mV
    8 = -7.9mV
    9 = 31.78V
    10= 31.8V
    11= 31.8V
    12= .045V/AC... aka(45 mV)AC correct??
    These readings were all taken with stereo turned on with the dimmer switch engaged, (which is the only way the stereo lights stay on at this point). Running through a dim bulb tester with a 100 Watt brand new Halogen light bulb. It starts up bright, dims down to about half power within 3 seconds or so. I hear zero clicks of any sort of relay.
    I know most people on here know their basic electronics, and I sure do appreciate you guys taking your time with me not knowing much. I know I could've picked better receivers to start with too I just couldn't pass this up!
     

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