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MULTI-CHANNEL PROGRAMMABLE TIMER

by Noel Rios

Circuit Description ý Construction and Assembly ý Checking and Troubleshooting ý Setting Up the Device ý Sources and PDF

MULTI-CHANNEL PROGRAMMABLE TIMER

In many situations, you need a gadget to turn on and off at a prescribed time. One example is the radio. In the morning you need to hear the most important news and traffic tips before you go to work. Another is the TV, as much as important as the radio in bringing the news. The list goes on and on.

It would be especially convenient if you could turn most of these gadgets on and off automatically! And, thatýs not all! What about having a maximum of four devices with four different on and off times. With the multi-channel programmable timer, you can connect a maximum of four fluorescent or incandescent lamps to it, as long as it does not exceed the solid-state relay current rating. For example, you can connect a lampshade to the gadget, along with a TV and a stereo.

Equally important, you can use the programmable timer to automatically set the charging time of rechargeable devices like lamps, drills, screwdrivers, batteries (particularly NiCd batteries or lead-acid batteries), and so on. Simple chargers do not have timers or charge-termination circuits in them to shut off the charger after some time, to prevent them from heating up and overcharging.

Another use for the programmable timer is to sequence a number of devices to automatically turn on or off at the same time.

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