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Heljan OO GWR 47XX 'Night Owl'

Kit: Zimo MX644D with Zimo LS18X13X13-1W Dumbo speaker, SACC16 with 2x 330uF Tantalums

Heljan's best steam model in OO yet, the 'Night Owl' 47XX is one heavy beast, and preparation for DCC including sound in the tender is straight-forward, ableit limited to what Heljan think you should use.

Access to the tender is innovative... pop off the water hatch and the boxes to reveal 3 screws, and the tender body simply lifts off.

The PCB is lightly tacked down with some tape, and is designed to take various mini-plugs into sockets around the edge. These seem quite unusual and non-standard, and we don't have plugs to match, so we take the approach of soldering everything we need (stay-alive and speaker connections) direct to the MX644D 21pin decoder. Rather than use a 25mm round speaker, which is what Heljan appear to have assumed you'll use, we opt for the better Zimo Dumbo LS18X13X13-1W which sits easily down into the cylindrical chamber, secured with Black Tack. Initially we wire up a pair of 220uF/25V capacitors, but even these are too tall to sit on top of the PCB, so we switch to using the excellent SACC16 stay-alive connection kit with a couple of 330uF/16V Tantalums on board.

The 'Night Owl' seems quite at home here...


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.

A bit of YouChoos poster art for your enjoyment!