Developer Tips & Hints

In order to google Place Search   and Place Library documentation there no option to use multiple keywords for searching. Therefore I have done this; I've created two PlaceService objects because I need to look at 'Pizza Hut' and 'KFC' both in single click. var service = new google.maps.places.PlacesService(map);             service.nearbySearch({                 location: pyrmont,                 radius: 50000,                 keyword: ['KFC']             }, callback); var service2 = new google.maps.places.PlacesService(map);             service2.nearbySearch({     ...

Schematic for Arduino controlled relay using optocoupler.   The input pins of the module work inversely. As we can see the relay will be activated when the input pin will be LOW because in that way the current will be able to flow from the VCC to the input pin which is low or ground, and the LED will light up and active the relay. When the input pin will be HIGH there will be no current flow, so the LED will not light up and the relay will not be activated. Optocoupler   PC817    Optocouplers and opto-isolators can be used on their own, or to switch a range of other larger electronic devices such as transistors and triacs providing the required electrical isolation between a lower voltage control signal and the higher voltage or current output signal. Common applications for optocouplers include microprocessor input/output switching, DC and AC power control, PC communications, signal isolation and power supply regulati on which su...