Heljan O Gauge Class 24 diesel (XL socket version)

Kit: MS990L; YLR603010

Heljan's Class 24 has evolved within this 'XL' socket version, which means 'almost' a plug-and-play.

Remove the blanking plate...

Unscrew the adapter to reveal some space beneath, but not quite enough for the speaker we have in mind, so we leave that space unused.

As is normal for a Zimo MS990L in a XL socket, we have to remove (or bend back in this case) some of the pins on the ends of the headers, otherwise they foul on the plugs in the model. There are more pins on the MS990L decoder than the header sockets in the model allow for!

The pins for servos are also different between the socket and the MS990L, and since there are no servos in the model, we can safely remove that entire header socket from the model.

Test-fit the decoder to make sure everything fits where it should, and doesn't touch where it shouldn't!

We've soldered our speaker (YLR603010) wires direct to the decoder pin feet, as we don't have a 2pin plug suitable for connection into the Heljan board. In fact, we added wires for a 2nd speaker, but it turns out to perform very well with just the single YLR603010, so we just stick with that.

The speaker can be attached with a couple of strips of BlackTack, directly on top of the decoder. There is just the perfect height available for this under the roof.

Not going anywhere without a driver...!

Back together for testing, just waiting now for numbering and weathering!

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.