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    • February 1, 2019 6:15 AM EST
    • Paul Norton said:


      If you are running battery power, using the smoke unit is not a good idea as it will shorten your run time. Unless it is a very big battery.

      I'm running my locos on battery power and my Forney does have a smoke unit. It was suggested to me to put a switch inline for the smoke unit so that if I'm not actively using it, I can turn it off. I've done just that and when it's on I have noticed a steep decline in run time.

    • January 31, 2019 8:49 PM EST
    • From my experience using two 4-wire connectors would be better than one 8-wire connector. The larger the connector would more difficult to connect and disconnect. That many wires on one side would also be stiff and help derail the tender or catch on the draw bar.

      If you use an LED for the headlight you can use a CL2 LED driver and bridge rectifier to power the headlight from the motor. The headlight would stay on in both directions, except when stopped. I have a picture of the tiny circuit board I made for my Pacific. But unfortunately I can no longer post pictures here.

      You might be able to do the same thing with the classification lights.

      If you are running battery power, using the smoke unit is not a good idea as it will shorten your run time. Unless it is a very big battery.

    • January 31, 2019 6:13 PM EST
    • K4 Pacific wiring:


      The wiring is so convoluted, I rewired to this: (track power DCC, but only save 2 wires for battery

      1. green, one side of chuff switch (no change) (goes to ground on chuff)
      2. blue, other side of chuff switch (no change) (goes to chuff trigger input)
      3. black, ground for headlight (no change to wires)
      4. yellow, hot for headlight (no change to wires)
      5. red, power to smoke unit (no change to connector)
      6. black, gound for smoke unit (no change to connector)
      7. red, left loco pickup
      8. black, right loco pickup
      9. motor +
      10. motor -
      11. classification lights +
      12. classification lights -


      8 wires aren't a lot when you fire stuff up... notice no cab light either...



    • January 31, 2019 3:23 PM EST
    • John,

      Correct I will be using RailPro and battery installed in the tender.

    • January 31, 2019 3:21 PM EST
    • Joseph, It sounds like you might be running R/C. Am I correct? 

    • January 31, 2019 2:54 PM EST
    • So right now the lines needed are as follows:

      Motor +

      Motor -

      Smoke Unit +

      Smoke Unit -

      +5V supply

      Headlight return

      Marker return

      Firebox return

      Possible return for cab light but could tie to head light.

    • January 31, 2019 2:43 PM EST
    • My curiosity has got the best of me.  What are  all the connections that would require eight pins between the loco and tender?

    • January 31, 2019 2:23 PM EST
    • The JST connectors offer the largest selection. They com in 2 to 10 pin connectors. Here are some JST 2.54 mm. Their biggest downfall is they are hard to disconnect.

      They come in 1.o mm to 3.0 mm(I think) pin spacing. A lot of people use the JST 2.5 SM connectors for higher current. JST 2.5 SM .

      The JST 2pin connectors JST 2-pin like those used for R/C battery connections are popular. These are available with red, white or black housings.

      I buy the ones that I can crimp myself which allows me choice of wire color and some choice of wire size. Sometimes I use different connectors for different things.

      Power and lighting connectors don't have to be the same. I think size and ease of use will always be a trade off.



    • January 31, 2019 11:33 AM EST
    • Molex PicoBlade might work.  I assume you're driving the motor though this, though, so current is a concern.  This is similar to what's on the Hudson, and I doubled up lines for power.

      Digit-Key carries these.

    • January 31, 2019 10:55 AM EST
    • So I have an Aristo Mikado I am working on updating.  the version I got sadly only had these two, two pin connectors running from the engine to the tender.  With the updates I am going I am going to need a minimum of 8 pins put having a hard time finding a small inline connector.  While I could try and mount the female end of a connector to the tender body I haven't seen a good spot to do that either, so I am wondering if anyone has any connectors they have used in past?  I been digging through digi-key but haven't found anything yet.


    • December 27, 2018 10:05 PM EST
    • Martin Sant said:

      Cool little board. I did some quick research, looks like you can use Atmel Studio with the Arduino plugin to program these too.  Neato.

      Yea, I've used Atmel Studio with the F091RCs that Ive been playing with.  This one is a neat little board for smaller projects.  Here's a demonstration of how much space is on this.  I loaded the standard Blink sketch:

      Sketch uses 9928 bytes (3%) of program storage space. Maximum is 262144 bytes.
      Global variables use 660 bytes (1%) of dynamic memory, leaving 64876 bytes for local variables. Maximum is 65536 bytes.


      That's a lot of extra space on this thing.  Plenty of room for functions, or maybe an OLED screen library.

    • December 27, 2018 6:56 PM EST
    • Cool little board. I did some quick research, looks like you can use Atmel Studio with the Arduino plugin to program these too.  Neato.

    • December 27, 2018 6:32 PM EST
    • Interesting. I wish I understood more about them things. In school we never discussed micro-controllers, but I did have a class on vacuum tube theory.

    • December 27, 2018 5:47 PM EST
    • While I wait for some other hardware to show up, I thought I'd show the new STM32 board that I bought, to use in the handheld throttle, and probably other things.



      It's a 32 pin package, has an ARM Cortex M4 80mhz processor, 256k flash, and 64k SRAM.  All in a package the size of an Arduino Nano, and programmable with the Arduino IDE.  For the princely sum of $10 from Digikey.  Its shown next to a Pro Micro for size.

    • November 30, 2018 1:42 PM EST
    • I think your right ...the board must be diff for the cabeeses...

    • November 30, 2018 1:18 PM EST
    • Good deal... I think they can also be damaged if you put the heater power to the fan... I forget the exact voltages in the regulator board.


      So, my experience with the USAT regulator board is that it does not run the smoke unit very hard, but I would suspect almost perfect for the caboose.



    • November 30, 2018 12:52 PM EST
    •  First ..  my fan was toast .. and ... my board worked almost.. not enough power for some reason.. two boards , heaters,  later we had the right mixture , board/heater, fan combo..

      Dan had some from repairs he has done.. all good now !

    • November 30, 2018 12:43 PM EST
    • Can you tell us what the issue was?


      If you need a spare board let me know.



    • November 30, 2018 6:31 AM EST
    • Thanks  Greg

      Dan and I spent a little time on this smoke problem ..with what unit and boards he had we got a unit working great !


    • November 29, 2018 1:47 PM EST
    • Well, the fan is about 5v, try unplugging it and applying 5v to it directly... that will tell you if it is the fan itself or the regulator.


      I have tons of those regulator boards... that is the standard "new type" smoke unit used in the Diesels.