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Need Help: Speedometer Signal Converter

Discussion in 'Automotive Electronics' started by autofanatic31, Jul 16, 2012.

  1. autofanatic31

    autofanatic31 New Member

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    ok thanks again. I'll post some feedback as soon as I've had it built and tested.
     
  2. alec_t

    alec_t Well-Known Member Most Helpful Member

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    The risk of over-driving the ECU could be reduced by supplying the pulses from the divider (IC pin 9) to the ECU via a 10K resistor. I'd suggest trying that first.
     
  3. autofanatic31

    autofanatic31 New Member

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    ok, I'll do that.
     
  4. dave

    Dave New Member

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  5. autofanatic31

    autofanatic31 New Member

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    Just got the parts for the circuit. I can't find 1N6377G and 1N7377G. What are these parts? Are there other parts that can replace them?
     
  6. alec_t

    alec_t Well-Known Member Most Helpful Member

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    They're Transient Voltage Suppressors (my bad; they should both have had the same type number....1N6377). If you can't get hold of those, try googling for "Transient Voltage Suppressor" and pick an alternative with a breakdown voltage rating of ~ 15V.
     
  7. autofanatic31

    autofanatic31 New Member

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    ok thanks.
     
  8. autofanatic31

    autofanatic31 New Member

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    I've already searched all the electronic parts store here, but I can't find the 1N6377, and any other replacement. Can you change it to a different part that will still make the circuit function? Thanks.
     
  9. alec_t

    alec_t Well-Known Member Most Helpful Member

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    You could use 15V zener diodes instead (with anodes connected to ground). They won't offer as much protection against voltage spikes, however.
     
    Last edited: Aug 29, 2012
  10. autofanatic31

    autofanatic31 New Member

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  11. autofanatic31

    autofanatic31 New Member

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    Just tested the circuit today. It worked. Thank you very much for your help and patience.
    Without your help, I won't be able to finish my project.
    I'm forever greatful.
     
  12. alec_t

    alec_t Well-Known Member Most Helpful Member

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    Glad it works. Nice to know theory and practice agree :)
     

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