I installed an NCE 13sjr decoder in a Blue box GP 50. First I installed and Athearn circuit board that has the eight pin connector then plugged in the decoder, The engine runs and responds to commands so I think I have the wires on the right tabs but the light immediately comes on dim when the engine is put on the track, Turn on the headlight and it becomes bright turn it off and it goes back to dim, If I run the engine on DC the light only comes on and brightens when the throttle is increased which is normal. In DCC the light comes on dim immediately and the engine requires more throttle than in DC. Any idea where I scewed up? I'm using an NCE power cab.
Marty C
Did you remove the motor and isolate the bottom brush contact from the frame with some electrical tape between the motor and frame?
CVs 120 and 121 control the lighting functions on an NCE decoder, so you have to change the values in these CVs. Note, too, that for LEDs you must add 128 to the desired value.
I don't understand why you installed an Athearn board instead of using a D13SRJ decoder and directly wiring a harness for it instead of going through the Athearn board. The Athearn board may be causing the problem, so I always remove them.
Cacole,
Yes, I isolated the motor from the frame. About using the board, the simple answer is I didn't know I could directly wire the decoder to the older engine. I had the decoder but I thought I had to put a board in first. Live and learn. I will try the CV adjustment but I don't think that is the issue. My guess is that somehow I am getting electrical power from the track to the light independently.
If you used the typical AThearn board, it has both an 8 pin socket and a 9 pin connector, and there usually is a dummy plug on the 9 pin connector for DC operation. If you plug the decode rinto the 8 pin socket, you MUST remove the dummy plug on the 9 pin. Since that's all hanging in there, you can also unplug the harnedd from the decoder and use the 9 pin plug. That way you KNOW the dummy plug was removed.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I thought Athearn DC boards were 1.5V output. The dummy plug could be causing a problem. You might want to confirm voltages the bulb is getting. Blue Box locos came with 12V bulbs.
Richard
I have a couple of DCC engines that have dim and bright settings for the headlight. When going forward the light is bright and when in reverse the headlight is dim. Using Function 7 (F7) on my throttle will change it to bright all the time or back to bright/dim. If the engine has lights on both ends, then the reverse light does the same. This may not be the same on yours but try using F7.
-Bob
Life is what happens while you are making other plans!