VR F class by Roco

Updated: Dec 15, 2020

Items used:

ESU 58823 LokSound 5 DCC Micro decoder with Next18 loose wire harness

ESU 50321 11x15mm sugarcube speaker

DCCSound Stay-alive circuit

8 pin plug


The body is first removed from the running boards by removing the radiator grille.

Very little room exists for a decoder, stay-alive and speaker in the model. For reliable running, the model necessitates fitting of a stay-alive circuit to the decoder, to overcome short power interruptions.

Decoder installation

The V5 Micro decoders comes with an 8 pin ribbon cable. Unfortunately the cable does not fit in the cab, so it's swapped out for a Next18 harness with loose wires.

Ribbon cable with 8 pin plug:

Ribbon cable swapped out for 8 loose wires:

The 8-wire harness of the decoder is shortened to be about 30mm long. A spare 8 pin plug was then used so the decoder could be removed in the future if required. The 8 NMRA wires were then soldered to the 8 pin plug.

Stay alive and speaker

The stay alive comprises one, 25V 470 uF capacitor, 1N4007 diode and 100 ohm 0.5W resistor.

The speaker is a 11x15mm Sugarcube style one, and must be so small as to fit in the model. Normally a larger 13x18mm driver would be used, but there just wasn't room in this model.

A small amount of material is used from the cab end window glazing piece to aid re-fitment of the body. The body is then carefully refitted over the finished chassis. Reassembly is completed by refitting the radiator grille molding.


PO Box 320, Buninyong, VIC 3357

0487 475 222



© 2021 DCCSound