One issue I've had occasionally using Digitrax decoders on KATO locomotives is a poor electrical connection on the front contacts that slide under the frame slots. I don't know whether or not it's because Digitrax has variations in board thickness or what but I've found on several of my locomotives that the decoder boards will actually work themselves loose while running becuase the friction fit between the decoder board and the slots in the frame is a bit loose. I've been experimenting with different ways to solve this and have arrived at the conclusion that simple is probably best in this case. What I did was to simply add a bit of solder onto the front contact pads that slide under the frame slots which makes the boards fit tightly into place. You may have to shave a bit of solder to get them to fit, but I've found this greatly improves the reliability of the of locomotives I've done this too and I've yet to have one work loose again. Don
Don, It is exactly because the board thickness is too thin on some runs. My easy fix depends on swaping out the couplers for MT couplers. I save the little foil strips from the Kato coupler and fold it a few times and use a jewelers screwdriver to press into place in the frame slots. So when I insert the decoder, they are a snug and tight fit. No problems so far. So this is an alternative to the solder method. For the P42/PA/E units and the F unit style of decoder, then best way is to solder the motor leads to the pad. That little gray button does not assure quality contact if the board is in the thin side in a similar manner as you mentioned in your post.
and I remember feeling a little put-off doing that solder drop on the P42's ... thot I was a little off, but seems to be the best practice ... failure proof ... had lost 1 of the little bugger grey things before I gave up on them ...
Ive been having to put solder on the new run Digitrax decoders as they switched to a thinner pc board so it doesn't make good electrical contact. Another Digitrax goof!
