Heljan/Hattons O gauge LNER A3 with MS sound

Kit: MS950; YLR603010

Back to the Heljan A3, with the MS950 this is a simple plug-and-play for the sound decoder.

However, we decide to go with a larger speaker than will fit the aperture in the tender (under the decoder socket), so we mill out the hole a bit larger (quite a long job, but the result is worth it), fitting in our 3W YLR603010 traditional box speaker.

Be careful to ensure alignment of the decoder in the socket is correct... the MS950 has 34 pins, but the 'L' socket has 36, so has to be done correctly.

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.