Bachmann 35-556RA decoders do not fit Roco Hf110c or Mh6 H0e locos

I have been trying to obtain  Roco 10735 DCC decoders, the ones with the 90 degree pins, to fit into my Roco Hf110c and Mh6 locos.


Having had a great deal of difficulty in obtaining them, they appear to be out of production, I thought that the Bachmann 36-556RA E-Z Command 90 Degrees 6 Pin DCC Decoder would do for now.  It was a little larger that the Roco decoder but it fitted nicely into the locos. The only problem is they do not work!

Bachmann 34-556RA dcc decoder

Having bought two Bachmann decoders I then find out that Roco have reversed the pinouts on their locos so that only their decoders face the right way to allow the cab or tender bodies to fit! Either that or Bachmann are the culprits!  Whoever was responsible is immaterial as it means that you cannot use the Bachmann chips in Roco H0e locos.

Roco do not mark the number 1 pin on their loco sockets or chips so you find this out the hard way when you cannot program the chip and the loco does not respond. It was only by using my ESU DCC decoder Tester that I was able to verify this by comparison with a Roco chip without burning out the Bachmann chips. This device is worth its weight in gold as it allows you to test, program and diagnose problems with almost any make and model of DCC decoder, both normal and those fitted with sound.

ESU Decoder Tester 3

It may be possible to remove the connector from the Bachmann units and re-solder it onto the other side of the board to make it fit. This is not something I will try myself as my eyesight is now just too poor to attempt working on such a small component!

I shall therefore have to look for an NEM651 compatible 6 pin chip which has leads long enough to carefully bend to 90 degrees to fit my Roco locos.