Transistor Substitution for (don't laugh) a Sanyo DCS-3500K

Discussion in 'Solid State' started by ringading, Sep 9, 2017.

  1. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Working on a quad unit and need to find a sub for a little 693F transistor. I will be pulling these to see if they are good but am waiting on the SM as there is no indication on the boards for ECB orientation.

    upload_2017-9-8_23-9-58.png
     
  2. Goldie99

    Goldie99 Well-Known Member

    Messages:
    540
    Location:
    The original Boston, UK
    If you look on the 693F (2SC2814) datasheet you copied & pasted, the next section down shows the ECB pinout.... they are still available.

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    Attached Files:

  3. redk9258

    redk9258 Super Member

    Messages:
    1,161
    Location:
    Illinois, close to St. Louis.
    A 1970's quad receiver has surface mount transistors? I doubt it.
     
  4. Goldie99

    Goldie99 Well-Known Member

    Messages:
    540
    Location:
    The original Boston, UK
  5. redk9258

    redk9258 Super Member

    Messages:
    1,161
    Location:
    Illinois, close to St. Louis.
    Maybe that is the modern equivalent? Same die in different package?
     
  6. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Think I have the wrong data sheet - it is the only 693F I could find online.

    Here is the little bugger. It is marked as 693FS.

    upload_2017-9-9_10-58-53.png
     
  7. llwhtt

    llwhtt Super Member

    Messages:
    1,092
    Location:
    SoCal
    2SC693F is a Sanyo transistor, you might find more with the complete number.

    Craig
     
  8. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Again, I am not sure these are even the problem. Since I dont know the ECB layout I am checking voltages at all three pins on both sides to see if there are any differences. If there aren't, then I imagine the issue could be in the tone amplifier or the quad decoder board somewhere.
     
  9. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Thanks llwhtt - I can find the 2SC693 online but all I find is the TO-92 case. Could this be an early or Sanyo-specific version?
     
  10. llwhtt

    llwhtt Super Member

    Messages:
    1,092
    Location:
    SoCal
    When Japanese transistor numbers are assigned they are assigned to one manufacturer, for example all 2SC693s will be Sanyo, all 2SD555s will be NEC, all 2SB554s will be Toshiba. Unlike American, possibly European, manufacturers several made the same transistor. I wouldn't worry about the style of the case, I don't think that case style hasn't been make in years.

    Craig
     
  11. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Well I don't think that is the problem. Compared voltages between that transistor on both boards and they are the same.
     
  12. llwhtt

    llwhtt Super Member

    Messages:
    1,092
    Location:
    SoCal
    You never did say what your problem is.

    Craig
     
  13. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Don't know much about quad receivers. There are 5 settings on the front for 2/4 channel.
    • 2-channel
    • matrix 1
    • matrix 2
    • matrix 3
    • discreet/tape CD-4
    In 4-Channel mode (switch on back) listening to front channels I get:
    • 2-channel - clear
    • matrix 1 - clear
    • matrix 2 - distorted
    • matrix 3 - distorted
    • discreet/tape CD-4 - clear
    Listening to the rear channels I get:
    • 2-channel - nothing but some water noise on the left channel
    • matrix 1 - distorted
    • matrix 2 - distorted but louder
    • matrix 3 - distorted
    • discreet/tape CD-4 - distorted but louder
     
  14. f0427ea

    f0427ea Member

    Messages:
    59
    2 channel mode just duplicates stereo on the rear channels , matrix 1,2 and 3 sends the signal through the decoder in receiver , and discreet-CD4 sends a separate signal to each channel by way of RCA jacks on back , for hooking up a 4 channel tape deck or CD4 decoder . a lot of quads strapped the front and rear channels together when run in 2 channel mode , to increase the output . hope this helps a bit , sounds like you have more than one problem going on (wonkey left rear channel and tired decoder ?) all these old quads are pushing 40+ years now and getting tired , I got more than a few that have age related problems of their own.
     
  15. f0427ea

    f0427ea Member

    Messages:
    59
    the service manual (when it arrives) will help you figure out where the signals going , it can get a little goofy or complex whichever way you want to look at it , all the quads I got seem to want to do it a little differently.
     
  16. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    I usually stay away from quads. I am not skilled enough to read the schematic to figure out where the signal is going (still learning). I am trying to work it out in my head as to where a fault might lie. If it does pass the signal through the SQ board for the Matrix settings and through the CD-4 board for CD-4 then perhaps I have issues in both boards?

    The SQ board looks fairly simple (compared to the CD-4 board) with a ton of 2SC537 transistors. If anyone knows a good sub please chime in as I wasn't able to find any mentions of one here on AK.

    2SC537

    Polarity: NPN

    Maximum Collector Power Dissipation (Pc): 0.2 W

    Maximum Collector-Base Voltage |Vcb|: 20 V

    Maximum Collector-Emitter Voltage |Vce|: 18 V

    Maximum Emitter-Base Voltage |Veb|: 5 V

    Maximum Collector Current |Ic max|: 0.1 A

    Max. Operating Junction Temperature (Tj): 125 °C

    Transition Frequency (ft): 115 MHz

    Collector Capacitance (Cc): 6 pF

    Forward Current Transfer Ratio (hFE), MIN: 120

    Noise Figure, dB: -

    Package: TO92
     
  17. ringading

    ringading AK Subscriber Subscriber

    Messages:
    527
    Location:
    Auburn, WA
    Bump anyone?
     
  18. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

    Messages:
    1,200
    Location:
    Victoria, Australia
    KSC945 should be a good sub spec wise for the 2SC537 but l think the pinouts may be different, l can't seem to find an orig datasheet. Can you see what the gain ranking is on the 2SC537's? the gains are as follows for the KSC945's.

    Classification hFE R 40 ~ 80
    O 70 ~ 140
    Y 120 ~ 240
    G 200 ~ 400
    L 350 ~ 700
     
  19. gpounce32768

    gpounce32768 AK Subscriber Subscriber

    Messages:
    365
    Location:
    Baltimore, MD USA
    Heres a thread on a sanyo dcx6000 resto- a different but related system, the overhaul involved replacing blown obsolete metal can transistors, so perhaps analagous here. I think a fairly close parametic sub for the small signal transistors would work fine. Hate it when there's no indication on the board, or the schematic contradicts the board....
     
  20. Oldsansui441

    Oldsansui441 AK Subscriber Subscriber

    Messages:
    1,200
    Location:
    Victoria, Australia

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