Heljan OO Class 14 Teddy Bear with Zimo Sound

Kit: MX648; IceCube18X13X07-1W; SACC16 + SuperCap17000uF

A bit of a bird's nest of wires in this Teddy Bear from Heljan, and very little space to play with, but we've managed to cram in a decent level of kit! The stay-alive is particularly good and important in this loco as the pickups are not the best, despite it being a heavy model.

The factory PCB needs to come out if we are to stand any chance of getting our desired kit in there.

Heljan's wiring colours are very confusing, so we label everything carefully as we disconnect!

Since the oriignal PCB is gone, we have to add our own resistors to protect the lighting.

The IceCube speaker sits at the front, just about perfect for the space. Initially we put the decoder behind it to test, but it will have to move when we fit the stay-alive.

The rear space is spot on for the SuperCap - just ensure that it is properly insulated with Kapton tape from the chassis, as the case of the SuperCap is the GND connection for it!

Decoder and SACC16 perch on the speaker, and the whole thing just about goes back together! Might have been easier to go with a coupler of Tantalums for stay-alive, but the SuperCap certainly performs!

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