I want to install a DH123p into a Bachman Spectrum 4-8-2. In the tender there is a small circuit board with a 8 pin plug. I know I have to remove this to plug. The decoder has an 8 pin plug but the plug from the decoder will fit both ways and there does not seem to any indication of which ways it goes, I don’t want to destroy a decoder by wiring it wrong. Does anybody know which way it goes. Thanks
Usually, there is a small arrow head painted on the board indicating what pin one is. Usually if you do it backward, the worst that will happen is that the engine will run backwards when you indicate forward and the lights might not work correctly. Haven’t really done spectrum in awhile so i don’t remember if you have to make changes to the board.
I’d check the Digitrax forum in Yahoo before taking a chance. There are some real experts there.
You can’t damage anything by putting the 8-pin plug in backwards - they designed it that way on purpose. The worst that will happen is the loco will run reverse when you try to go forward, and vice-versa.
Bachmann engines usually have a pair of capacitors on their circuit board - these can be removed, actually SHOULD be removed. If you don’t, wierd things happen, like running fine in reverse but slow in forward. Check the decoder install guide on the Digitrax site, i believe they mention the Spectrum steam locos specifically.
–Randy
The wiring code is:
Pin#1-Orange-+ motor lead
Pin#2-Yellow-Rear light
Pin#3-not used
Pin#4-Black-left rail pickup
Pin#5-Grey-- motor lead
Pin#6-White-Front light
Pin#7-Blue-light common
Pin#8-Red-right rail pickup
Look at the pin the orange wire from the decoder is soldered to. This is the #1 pin and should orient the plug the right way. I made a DCC folder on my computer and in my files that i keep such informattion in. It has proved very helpful.
Also, I forgot to add that you should check the Bachmann and Digitrax websites to see if there are any special instructions or tips on decoder installation in this locomotive. I am also a member of the Digitrax Users Group on Yahoo which has been very helpful.
Hey ! Thanks gents much appreciated. I will take a better look at the circuit board and Digitrax.[:)]
Even if you install the decoder backwards, the only effect will be that the motor will run in a reversed direction, so if the motor runs backwards, turn the plug around.