What to do with a Technics SL-1700 with a bad chip?

Discussion in 'DIY' started by ontheroad303, Jul 12, 2017.

  1. ontheroad303

    ontheroad303 AK Subscriber Subscriber

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    So I bought a Technics SL-1700 that was spinning a bit fast and it ended up being a bad motor control chip that was causing it. Ended up finding an awesome Sansui turntable to replace it.

    Now that I have the 1700 lying around, I considered parting it out, but then it occurred to me there might be some other uses for it. Would it be worth it to build a custom turntable with the working parts or maybe an alternative use I haven't thought of?

    Any help greatly appreciated.
     
  2. Binkman

    Binkman Addicted Member

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    Greetings; Why not repair it? pretty sure that control board has adjustment for speed? So are you sure it's a chip?
     
  3. blhagstrom

    blhagstrom Mad Scientist, fixer. Subscriber

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    I have heard of tables with bad chips.
    Some chips are available, sometimes from cheaper tables.
    I'm not sure where the 1700 fits in the $$$ stack.

    I've sold tables with problems to people willing and able to fix them.
    I hate working on them.

    If the 1700 is known for bad chips, then most are probably messed up like yours so no one needs parts for them except for the chip.

    But I've parted out junk and sold everything so who knows.

    You could use it as a spin clean type cleaning table with a dishwasher.
     
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  4. ontheroad303

    ontheroad303 AK Subscriber Subscriber

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  5. shrinkboy

    shrinkboy AK Subscriber Subscriber

    contact KAB, look at the service manual on Vinyl Engine, etc. this is a solvable problem. if you can't figure it out, someone here can. patience.
     
  6. gadget73

    gadget73 junk junkie Subscriber

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    If you can't repair it, it would perhaps work as a base for an RCM. All you'd really use there is the platter.
     
  7. Binkman

    Binkman Addicted Member

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    https://www.vinylengine.com/library/technics/sl-1700.shtml

    the eboy lists a very broad range of part out prices to repaired but not bad TT design. Might be able to get a new board? If cosmetics look good? big bonus. Perhaps dig up 1700's info on the TT forum? Read many who restored various Sl models.
    ------
    My 1600mk2 needed a logic chip for the tone arm logic I got from china, a diff symptom and chip for listed models, but might be few more bucks in your pocket. Good solder pads etal. I found easy to work on.
     
  8. slimecity

    slimecity Super Member

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    Or if its spinning slower than usual, some kind of lazy susan arrangement for the dinner table?

    Shame - this would be a nice TT if working properly. Have you investigated the function of the chip and whether a modern replacement could be subbed in? May require some pin-tweaking if you are in luck?
     
  9. ontheroad303

    ontheroad303 AK Subscriber Subscriber

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    I'm new to the world of vintage gear, so I greatly appreciate all the feedback and ideas. The turntable is in excellent physical shape and I'm leaning towards repairing it. Part of the reason I bought the 1700 is that many of the parts are interchangeable with the SL-1200's.

    There is a very reputable repair shop in my area which I took the table to, they let me know it's a bad motor control chip, but could be (in theory) a bad board overall.

    @shrinkboy @Binkman @slimecity - Just read through the service guides/manuals on Vinyl Engine. It seems as though trying to replace the IC (AN630) would be a good start. Hopefully this works instead of replacing the whole board. Do any of you know off hand if an AN640 will work as a replacement?
     
  10. slimecity

    slimecity Super Member

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    I think you need to first work out what the chip actually does (not being a smart arse, I actually dont know what it does....), then also check the pinout against any new chip.
     
  11. Binkman

    Binkman Addicted Member

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    lets back up a little. See service manual pdf page 4; speed control adjustment. Is there any affect adjusting the speed?
     
  12. elnaldo

    elnaldo Addicted Member

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    I bought an An-6675 IC replacement directly from Panasonic some years ago. It was around $40. It's the motor control IC. I'll search the old emails to see the exact part and web site where I've got it. Also replaced some analog switches that went bad . But the repair Shop will know. The TT can be repaired if you invest some $ on it.

    Edited: AN6675 , not AN6680
     
    Last edited: Jul 20, 2017
  13. ontheroad303

    ontheroad303 AK Subscriber Subscriber

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    @elnaldo was that chip a functional replacement for a SL-1700 or was it for another TT?
     
  14. elnaldo

    elnaldo Addicted Member

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    SL-1700 and all the "1200" family, there are several TT that share the same board.

    This PNG image will help you (credits to deckdoctor.com.au, no affiliation)

    https://www.dropbox.com/s/mmngwwlrmln4gdq/HELP_SL1200.png?dl=0

    EDITED: Looking at this pict, I've replaced the AN6675.not the AN6680. But you need to diagnose the problem properly.

    I had to replace, as stated, some analog switches in the pitch board too, some 4066 or similar (I don't remember exactly the ICs, but there are some on the pitch board)

    Here is part of the e-mail I received from panasonic in 2014:

    "Thank you for your inquiry. Part AN6675 subs to RFKFAN6675, which are currently on back order with estimated shipping date of three weeks from the date of purchase. Your cost is $29.46

    There is also a $6.25 – $16.95 shipping/handling fee within the U S, as well as your local taxes, attached to this order. Please note that pricing and availability are subject to change.

    You may call (800) 833-9626 to order. Please note that this item is not available to order on the Internet website.


    Thank you,
    XXXX
    Admin Department
    PCEC/CSG

    If you need to respond, please make sure you send it to:
    npcparts@us.panasonic.com
     
    Last edited: Jul 20, 2017
  15. ontheroad303

    ontheroad303 AK Subscriber Subscriber

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    Thanks @elnaldo, you're the first source I've heard that said it's a viable replacement. I've been seeing a few sources say that the AN6675 will be compatible with an SL-1700, but nothing online that's been definitive.

    Based on what my repair guy explained and that 1200 help sheet, it seems the AN6675 would be a good place to start. Finding the original AN630 will be much more difficult than previously expected (unless someone has one up on Bartertown - thinking about taking the plunge).
     
  16. elnaldo

    elnaldo Addicted Member

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    The SL1700 I've fixed has the same board you see on that pict, and AN6675 was the original part, as detailed in the service manual. Please remove the cover and check by yourself if we are referring the same TT . Check the service manual too. I didn't replace one different IC, just replaced the AN6675 with the newer RFKFAN6675 part sold by Panasonic.

    The TT I've fixed is "SL-1700 MK2", I see the circuit is quite different from "SL-1700" .

    I don't see any AN630 on that board.
     
    Last edited: Jul 20, 2017
  17. ontheroad303

    ontheroad303 AK Subscriber Subscriber

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    Yeah did some more research and saw the same thing. Looks like I'm still on the hunt for an AN630. Thanks @elnaldo, patience is key.
     
  18. elnaldo

    elnaldo Addicted Member

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    Try to email that parts service who sold me the AN6675
     
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