Heljan OO AC Railbus with Zimo MS sound

Kit: MS440C/D; RE Boomer 18X13X13

A simple install into our Heljan AC Railbus using a 21pin MS440 decoder, 18x13x13 Boomer speaker and the standard 1000uF capacitor that comes wtih the MS440 for stay-alive.

We have to remove the ladders and pop out the bottom fixing for the handrails in order to get the body off.

The body splits in half and the top half lifts off. A plastic strip is unscrewed which allows the model's PCB to be accessed.

There are no pads for a speaker in the model - just a 2pin socket with no plug provided - so we solder speaker wires direct to the decoder instead... normally we'd use pruple wire, but these wires may be visible through the windows, so we use black intead.

The capacitor will join to the striped blue/black wires.

We figure out a good spot for the speaker and capacitor, and fix them in with BlackTack. There is no way to hide these completely from view, but they are not too bad tucked in by the pillars.

Fairly short wires and neatness is in order, but quite straight forward really.

Please note that these guides are provided as useful resources for you, as-is. YouChoos cannot be held responsible for errors in the information, or for any damage caused to your models or equipment if you choose to follow any of the steps detailed here.