Train'in Camp - DCC Decoder Installation Hands On Clinic

The Piedmont Division of the NMRA offered a clinic on beginning DCC Decoder Installation Clinic on June 6th, 2009. I couldn't pass that up, so I signed up.

The class was taught by Ovidiu Trifanescu, Scott Chatfield and Howard Goodwin. Perry Lamb was also there.

Here are my important learnings from the class.

1. Take a digital camera EVERYWHERE you go. I could have really used one to take photos of the steps.
2. Using a lower temperature on your soldering iron extends the tip life.
3. When you buy a soldering iron get one that has a replaceable hand piece and a replaceable tip. The base will usually last much longer than these pieces. Other benefits are adjustable heat and an on/off switch.
   
4. The Weller WCL100 is highly recommended for model railroading.
5. Best solder to use is rosin solder that is .032 diameter with 60/40 lead content. This is becoming hard to find and the new solder doesn't work as well.
6. Flux is the secret to good soldering. It cleans the surface of the work and your soldering iron tip. It encourages the liquid solder to flow. Rosin paste solder is fine and liquid flux like Tix is recommended. Use the paste flux to clean your iron tip.
7. Water soluable flux is an aggresive cleaner but not as good for decoder installation as it contains zinc chloride.
8. Don't ever use resistance soldering units for soldering DCC or other electronic components.
9. Tony's Train Exchange has a voltage and amperage meter board combination that can be used for testing. You can put one of this on your layout just after the command station and itl will provide accurate volt and amp information on the rails. Runs about $49 and is called RR Amp Meter. http://www.tonystrains.com/technews/rrampmeter.htm
10. LaBelle #107 or Conductolube is excellent for cleaning locomotive metal parts and for lubricating.
11. A regular voltmeter will not accurately read the voltage on a DCC track.
    
12. If a locomotive is drawing one amp or more, replace the motor.
13. Most DCC decoder installation failures are related to the lights.
14. Green corrosion on circuitry is usally caused by acid flux or acid flux solder and must be removed by thorough cleaning.
15. Kapton tape is recommended (but expensive) for taping and insulating wires. You can buy it at Uline http://www.uline.com/BL_6407/?pricode=WE491
    
16. A locomtive foam cradle (Micro Mark) is essential for DCC decoder installation.
17. JST connectors are what are used on most decoder harnesses and are keyed to only go one way. Harness wire colors are standard.
18. You can break the wires if you aren't carefull when removing a decoder from a JST. Grab all the wires at the same time and pull.
19. Do your decoder installation in stages. First, hook up the power wires and insert a "Dummy Plug" into the JST harness and test on a DC (not DCC) track to make sure the wires are installed correctly.
20. When you install bulbs, use 14 volt bulbs or at least 12 volt. Bulbs come in different millamp rating. 50 mamp is not recommended - will burn out. 15-20 millamp is the best.
21. A 1.5 volt lamp with a 600 ohm resistor will work.
    
22. DCC track normally is at 13.75 volts, not 12 volts, which is critical.
23. (Track Voltage - Bulb Voltage)/Amps - Ohms and use 13.75 as track voltage.
24. Leds take 5 to 20 mA, and do not exceed 10mA.
25. LED: andode is positive and has the long lead. Cathode is negative and has the short lead and the flat surface on the diode head.
26. The resistor is best placed on the cathode lead.
27. Digitrax series 165 decoders are built for LED's.

It was a great class!