Most of the DIY project schematics do not include a power supply. Most of the projects require +5VDC REGULATED. They can either be powered using a +5V regulated wall transformer or users can incorporate a linear regulator and capacitor and power them from a +7.5V to +18V unregulated wall transformer.

Europe, California and other locales have mandated power supply efficiency standards that can, at present, only be met by switch mode power supplies. I have tested two +5VDC regulated switch mode power supplies and found them to be X-10 and Insteon compatible.

The schematic below shows how to add a linear +5V regulator and use power from an unregulated DC wall transformer. C1 is only needed if the lead to the device is more than a few feet.

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