DDC DECODER PROBLEM

[madmodeler]

HI ALL!

I HAVE A NEW DIGITRAX DECODER, DN163AO DECODER, IN AN  ATLAS 'N' SCALE SD35 LOCO.

I RECEIVED THIS DECODER AS A REPLACEMENT FOR A DECODER THAT WENT BAD BY DIGITRAX. I INSTALLED THE DECODER, PROGRAMMED IT WITH NO PROBLEMS. TWO DAYS LATER WHEN I TRIED TO USE THE LOCO, THE LOCO WOULD RUN VERY,VERY SLOWLY.

I RESET ALL CVS ACCORDING TO DIGITRAX'S INSTRUCTIONS AND REPROGRAMMED THE DECODER. THE LOCO RAN FINE. THE NEXT DAY, THE DECODER WOULD NOT RESPOND THE WAY I HAD PROGRAMMED IT. IT IS LIKE THE DECODER IS LOOSING IT'S  MEMORY.

ANY ADVICE WOULD BE APPRECIATED!

THANKS,

MADMODELER

 

[wm3798]

 Make sure the decoder is installed properly, and that the contact points with the motor and the frame are tight and secure.  The SD-35 is notorious for having loose connections.  If the decoder board is flopping around in the frame, you'll get the results you're getting.

There are two fixes.  First, before the decoder is installed, add a thin application of solder to the four pads that contact the frame.  OR, after the decoder is installed, use a pair of needle nose pliers to gently crimp the little ears of the frame down onto the contact pads.

You should also check to make sure the motor tabs are not making contact with the frame.  This may have been what killed your original decoder.  You can take care of this by slipping a small piece of insulating tape between the tab and the frame after installation.  Just make sure it's in securely and won't slip down into the motor during operation.  I put the sticky side against the frame.

Hope this helps.

Lee

[madmodeler]

HI LEE,

THANKS FOR THE ADVICE ABOUT MY DECODER PROBLEM. I WILL TRY WHAT YOU SUGGESTED AND LET YOU KNOW IF IT WORKS.

RANDY (MADMODELER)