SCR Throttles

Discussion in 'FAQs' started by leon1, Jun 18, 2007.

  1. leon1

    leon1 New Member

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    I am trying to find the article on SCR throttles in the Model Railroader June 1977 magizine. I would appreciate any help or suggestions
  2. woodone

    woodone Member

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    Wow! that is very old tech. Any reason you are looking for the information? :confused: I built one a long time ago, Peter Thorne design, from a book, Electronic Projects for Model Railroaders . About 1982 - I never did get it to work??:curse: I do have MR books back to 1976, any Idea what month? I would have to dig it out as books are packed away for a move.:eek:
    With all the new stuff out there, you could find something a little better and such.
    No DCC? :twisted:
  3. doctorwayne

    doctorwayne Active Member

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    Hi leon1, and :welcome1: to the Gauge. I'm glad that you brought up this topic, as I was unaware of this article. I went and checked my back issues and found the proper issue. I'll be sending you a pm regarding this, as the magazines have been promised to a friend.

    Wayne
  4. JR&Son

    JR&Son Member

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    MX033 PWM DC Motor Speed Controller

    The above is not an SCR, its a MOSFET
    Works VERY well though
    They make a cheaper version but it whines horribly!
    This one is good to 15 amps.
    I loaded one to more than 10 amps and it barely warmed up
    Both of mine needed minor repairs on arrival
    The 1st one, had bad solder joints at the speed pot
    The other one was missing a screw on the heat sink
    5 mins each to repair, versus a 5 year old, not very happy.
    Thats why I did not bother to send them back

    JR&SON
  5. leon1

    leon1 New Member

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  6. woodone

    woodone Member

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    Leon1,
    Let me see if i can put my hands on that copy,
    Like I said I have my MR books boxed up for a move. They are still in the house, so I will take a look- let you know.
  7. doctorwayne

    doctorwayne Active Member

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    I attempted to buy a pulse width modulating throttle from a guy nearby who was building them, but got no reply to my e-mails. I was told at the LHS that they haven't seen him for a while, so that one seems to be a dead-end.
    This sounds like it could be a good alternative to an SCR, which gives excellent low-speed control but doesn't have the capacity to run heavy double-headed trains on steep grades. Trains simply slow and die, even though the input is 16 volts AC.

    Wayne
  8. JR&Son

    JR&Son Member

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  9. doctorwayne

    doctorwayne Active Member

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    Thanks for the links, JR&Son. :thumb::thumb:

    Wayne