Liquid Ss is powered by 12 - 12.6 volts AC and will draw around 1200 mA.

For my power supply I connected a 2.5mm plug to the two white secondary taps of this 5 watt 12.6 volt transformer.
It's AC so it doesn't matter which tap you connect to the centre pin on the plug.

The two red wires are the primary taps, connect them up to the Active (Brown or Red wire)
and Neutral (Blue or Black) wires on the power cable and solder the earth to the case.
Put the transformer in an enclosure and your done.