Heljan O Gauge Bubble Car 121/122

Kit: MS440C; YLR302815; MGOLANG

The long-awaited Heljan Bubble Car in O gauge, looks good, let's look inside...

21pin decoder socket on a ceiling PCB, so should be simple for DCC. Provision for speaker is in the underframe - looks like it is designed for a 28mm round with screw mounts of some sort, but we can get one of our 2W YLR302815 traditional speakers into the space with minimal modification.

This Bubble Car has only 3 lighting outputs in use - directional heads/tail and interior lighting. The destination board lights are on the same circuit as the directional lights. Looks like the PCB has provision for at least one more set of lights - perhaps on another variant of these DMUs.

Speaker wires are provided in the underframe box. Our YLR302815 speaker needs to have its' lugs cut off and filed flat, then the screw mounts in the model must be removed and a slot cut for the wires to feed down - all quite well hidden and ends up nice and neat.

An alternative would have been the bigger YLR453520 in the luggage area - fits without modification, and the speaker wires provided in the model go straight past this area so would have been easy to intercept. We stick with the YLR302815 in the frame for this example though.

So, remove the screw mounts, cut the wire slot and fix in with some BlackTack - fairly snug so shouldn't be going anywhere.

On the top, we remove the blanking plate and fit our MS440C decoder, and an MGOLANG GoldCap array for stay-alive.

All works well, though we found the motor on this model to be rather noisy - hopefully quietens with running-in. Can't really hear the motor with the sound on anyway!

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