Resurrection of a 30yr old Tyco

Discussion in 'The Caboose' started by JR&Son, Dec 26, 2006.

  1. boppa

    boppa Member

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    1 a variable resistor IS a potentiometer.... what he wants is a wirewound variable resistor

    and pots/variable resistors either carbon film, wirewound, etc etc are not measured in amps!!!!!!!

    they are measured in ohms(ie resistance) and wattage (ie voltage times amps)
    also be aware when buying pots is that there a few different types
    ie
    linear/log/antilog/dual taper/ balanced taper etc etc

    all of these have totally different results `on the track' in terms of low speed running/speed `buildup' against `dial turning' etc etc
  2. boppa

    boppa Member

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    `BAD IDEA' 16vac is a bit higher(but not too high) to use as the Tx secondary voltage
    24v-would be around 18vdc(btw forget about using caps as filters in a dc layout- totally unneeded at all)
    if the Tx amps is sufficent then boosting the voltage is unness... and if the amperage is too low then trying to compensate by boosting the volts is a really reaaallllyy bad idea

    escaping smoke bad

    Couple of Tech Questions:
    #1 One already mentioned, Multi engines I know require higher amps, where does voltage come into play? Indirectly in the current equation Im guessing?

    same voltage ie 12vdc just different amps-bit like a car taillight and a mega shooting spotlight..both 12vdc-one draws mA the other 10's of amps- put either on 240v(probably 110v where you are) and both go bang....

    #2 Voltage ripple on the DC side, how much does the ripple come into play. The Tyco had no caps. I included 1 220uf on the prototype. Im assuming less is better. Does it help engine cooling? Keep in mind I do not have access to an Oscope so Im basically throwing the cap/caps at the end circut as good housekeeping

    no caps required at all for dc engines.....unless....

    some psu's actually used large value caps not for filtering-but as throttle/braking substitutes..
    due to the delay used to bring track voltages up/down they could simulate braking and acceleration

    but a pure dc loco (ie not dcc) requires zero/zip/zilch filtering to run at all
  3. Russ Bellinis

    Russ Bellinis Active Member

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    On a dc electric train, the voltage sets the speed of the electric motor which combined wtih the gearbox ratio sets the speed of the locomotive. Extra powered locomotives will mean extra motors which draws extra amperage.
  4. Gunny

    Gunny New Member

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    Old Tyco...

    I Still have my first Engine, a Tyco GP20. It is 42 years old and still runs, I did not switch it over to DCC, I am going to leave it as is.

    Gunny
  5. hiscopilot

    hiscopilot Member

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    I am simply amazed at all of the technical stuff you guys know.
  6. Gunny

    Gunny New Member

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    JR & Son : You are as old as you feel...

    Gunny
  7. Russ Bellinis

    Russ Bellinis Active Member

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    Part of my job as a transport refrigeration mechanic was tto troubleshoot electric motors, control circuits, and small diesel engines. It isn't a lot different from model railroading, only bigger!