Brakeman

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GCOR Rule 6.19 D (paraphrased)

When a train stops on a main track, flag protection must be provided

On a layout, torpedoes and fusees are a bit over the top, but a brakeman/flagman with a red lantern can add a twist to your next operating session. Adopt prototype practices and have your crews protect their trains when switching a town or otherwise fouling the main. Just don't forget to recall the flagman before leaving town!


Designed in the NMRA/PCR for DCC layouts

Assembly required

  1. V1.0-1.3: Use a track nipper to detach the base from the hand holding the LED.
  2. V1.4: Snap the base from the feet and remove any extra PCB frame from around the figure.
  3. Solder the two feet to the two small gold pads on the top of the base
  4. You can solder a wire (the clipped off resistor leads work well) to strengthen and align this connection
  5. Attach the weight to the top of the base next to (but not touching) his feet with double sided foam tape
  6. Place the large gold pads across the rails to light the red lantern.

Variation:

  • Make a "Safety Sam" to indicate track or rolling stock that must not be used/moved. Use 2 BLUE LEDs instead of one RED one - solder them "back to back, opposite" so that one LED's long lead is soldered to the "front" on the raised hand, while the other's long lead is soldered to the figure's "back" on the lowered hand. Using 2x Blue LEDS is necessary because the Blue LED's have a reverse breakdown voltage close to 5v, while the common Red ones seem to be able to handle 20v+. (DCC track voltage is ~15v...)

Clean track works best. Use violates UP Safety Rule 81.2.1, Step Over Rail

John Plocher, SPCoast.com

WARNING: This product may contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.




Brakeman Testplan Assembly:

  • SMT 1K0 0805 or PTH resistor on body top surface
  • Cut the LED leads to between 3mm and 4mm long
  • Edge mount the Red LED to the raised arm, polarity does not matter
    • Colors other than red: must use 2x LEDS, one on each arm, with opposite polarity

Testing:

  • Red LED:
    • Touch 9-12vAC to one "foot" and Gnd to the other,
    • observe RED LED on hand light up.
  • Other Colors:
    • Touch 9-12vDC to one foot and GND the other,
    • Observe ONE LED light up
    • Reverse the foot connections
    • Observe the OTHER LED light up

The end user will snap apart the base and body, solder the feet to the base and attach a lead weight to the base, making a figure with a LED lantern in its hand that lights up when placed on a HO model railroad track.




[edit]


V1.4 is effectively the same as v1.3, but

  • Has better documentation in the gerber files for panelization.
  • adds a couple of traces between the base and the figure to allow full panel prebuilds and easy testing - the 2 traces are intended to be cut during the final assembly process.
  • adds back the vias on the feet to allow for adding support wires to reinforce the solder joint that is prone to snapping off when Brakie is taken out of service and stuck in a pocket - and then sat upon...
  • The figure is now wearing a belt :-)

For best results when fab'ing, choose:

  • ENIG (gold) rather than a Hot Air Solder Layer (HASL) for the pads
  • White or Blue soldermask
  • Panalize = 1




The circuit / layout from 1.4, manually panelized into an 8x 10cmx10cm size.








This version is aimed at self-service orders and non-surface mount parts. The LED can be in either hand (up or down), and the base can be used as a fusee without Mr Stickman...

If assembling a fusee, stick a 1K resistor in one hole in the base, and one leg of the LED in the other, bending both "other leads" to meet where you can solder them together in the air.






An electronic DCC-track-driven figurine with a red LED




An electronic DCC-track-driven figurine with a red LED




An electronic DCC-track-driven figurine with a red LED





Resources

The schematic and PCB layout were created using the Electronics Design tools provided by Eagle CAD.

HowTOs

Downloads

  • Eagle CAD for Windows, Mac and Linux
  • SparkFun10mil.dru a 10-mil version of SparkFun's Design Rules Check
  • seeed-plocher-gerbers an EagleCAD cam processor definition file that you can use to create "gerber" and "drill" files for your fab house
  • makeboard shell script to collect EagleCAD's CAM droppings into a zip file for fabrication
  • SPCoast.lbr a EagleCAD library of parts used in these designs.