Dapol O Gauge Class 121/122 Bubble Car using Zimo MS Sound Decoder

Kit: Zimo MS440C; 2x YC23R round speakers + YLR302815 2W box speaker; SuperCap17000uF or 6x mini GoldCaps

With the availability of the MS440C sound decoder, the Dapol O gauge Bubble Car becomes easier to install sound into, without any modifications required for all of the lighting to work.

Underneath, we remove the 21pin blank board.

Our MS440C has a 17000uF SuperCap attached directly for stay-alive.

Fix the SuperCap (wrapped in Kapton tape) into the fuel tank, plug in the decoder, and that is the decoder/stay-alive done.

Alternative stay-alive could be the 6 mini GoldCaps, which give awesome performance - a little more fiddly to assemble, but worth the effort. The 6 GoldCaps are connected in series to create a 16V array:

In the seating area, we install a YLR302815 2W box speaker, using the 2pin plug/wiring loom provided with the model.

The speaker is secured with BlackTack.

Underneath there is provision for a pair of small round speakers, so we add in our YC23R 23mm speakers, soldering to the provided pads under the model's PCB.

Most of the sound output comes from the box speaker inside the body, which cannot really escape very well as it is enclosed. We therefore carefully 'open' a window on either side of the luggage area. This makes a massive difference to the overall volume levels, so well worth doing.

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.