Recent Interent searchs failed to list how to make my Athearn/Digitax Lamp Board upgrade successful, thus I’m writing to those who have not yet gotten their upgrades to fly, the first time.
I have several photos that show what I discovered and how I got my DCC Locomotive Decoder to use the 8-pin NMRA Std. plug on the “Lamp Board”, if I knew how to get them on this “community”, I would.
If you are lucky enough to get a Digitax RTR Lamp Board, with the Athearn Box marked “DCC-Ready”, you most likely can open the “shell” and remove and discard the “Jumper Board” plugged into the colored ribbon cable. Your 8-pin standard decoder plugs into the main lamp board and you’re done!
If you are like me, I have no plans to open the shell again AND I use the directional “lamps” while I’m running the HO Train, so I know before it moves, which way it’s going to go. The main disappointment I had with the Digitax (Internet) documentation was, they did NOT tell you to remove both 150 Ohm resistors “under” the circuit board, just above the flywheels and replace them both with 1,000 Ohm resistors. Wait! You’re not done yet! To make the “old 1.5-volt” light bulbs work, they (Digitax) uses two diodes (surface mount) in series with the 150 Ohm resistors as well as in parallel with the light bulbs. To get my L.E.D.s (Radio Shack bright white “hobby” L.E.D.s) to work, I had to remove those series/parallel diodes from the ends of the Digitax Lamp Board; CR1-CR4, CR5,CR6,CR8,CR9.
I did not expect all this work and you better be really good with a 40-watt pencil soldering iron and solder wick. I used a toothpick at the end, after I removed as much solder from the ends of the diodes as I could, the toothpick “popped them off” nicely and you then go back and simply clean up your mess. After the diodes were gone, my DCC Convesion of my Athearn/Digitax lamp board was complete. The L.E.D. wire polarity is easy to figure out, if you get it backward