The Skd 224 is a small switcher that started service in 1979. See Norwegian Skd 224 models in HO for all the details. On this page I will describe how I installed sound in this switcher.
The starting point is the NMJ Topline Skd 224. The decoder that will be used is the ESU 58823, a Loksound 5 DCC Micro. I will use an ESU speaker (10x15mm sugar cube). As this is a small two axle locomotive a power pack (also known as keep-alive) is a good idea. On the photo you can see the Train-O-Matic SPP but eventually I use an ESU Power Pack as the small pcb board of the ESU Power Pack is slightly smaller and fits better.
The disassembly has started. The original PCB is removed so we can see how to best fit it all.
Originally I thought that I can't re-use the original PCB but it is possible to keep it and that makes it a lot easier. To fit the Power Pack I removed some part of the frame. With a dremel I was able to do this quickly.
This shows the position of the Power Pack (in the front) and the decoder.
The original PCB has a NEM652 8-pin socket, the decoder has a NEXT18 adapter board. I soldered a 8 pin connector to the NEXT18 adapter board so it plugs-in easy. The ESU Power Pack is directly soldered to the decoder (per the ESU instructions).
Installation complete. The speaker fits in the wide part of the body shell. This photo also clearly show how I removed some part of the frame to fit the Power Pack properly.
Sound demos
A sound demo. The small switcher is picking up a conductor car to add to the freight cars.
A quick demo of how the small switcher now can run over tissue paper.