WARNING! Rapido GMD-1 ditch lights

[faraway]

So you would solder your Tsunami2 wires to the pads on the adapter and plug the adapter into the existing ESU motherboard that came with the loco?

That is not the plan. I intend to plug the Tsunami 2 21 pin sound decoder in the adapter and wire it via the solder pads directly into any locomotive with sufficient space. Candidates are my BN SW1500, CR GP15-1 etc.
The point is that a spare 21 pin decoder is not limited to 21 PCB equipped locomotive (e.g. GMD-1, IM GP10 etc.) but can be wired into any locomotive with the required space.
The GMD-1 motherboard is already completely replaced with a Tsunami 2 PNP decoder. I do not know if he GMD-1 PCB/motherboard is made by ESU or Rapido.

The 21 pin decoder, the adapter and the decoder plug on to the adapter. The adapter has solder pads on both sides of the PCB.



ps. Read the booklet that comes with the adapter. The 21 pins are "NOT" 1:1 connected to the solder pads. Most are but some are connected to other pads than you may expect!