Hi i am looking for very cheep wireless on off switch with one transmitter and several receivers. for simple example i need to switch off or switch on around 10 electric bulb(10m away) with relay through wire less. (One transmitter and 10 receiver). please advice.
Audio (ultrasonic frequency) is a possibility if distant isn't too great.
There are store-bought wireless devices which control over a short distance. Wireless doorbells., car & house key locators for instance. Not sure which gizmo lets you buy ten identical receivers, however.