detecting that a tv is on

[hgupta1]

To detect the state of a TV, you could use CR magnetics current sensors. If there is some sort of lightsource on the back of the TV (status LED, light coming out of the back of the tv), you could also use a CDS photocell. Both type of sensors can be connected to the Elk M1.

Which is the best CR Magnetics current sensor to get for connecting to an Elk M1?

I think my last post may have gotten lost in the site upgrade. I went to the CR magnetics website, and was a bit overwhelmed by the choices.

The sensor will be attached to a 42" Philips plasma tv, and then connected to the ELk M1.

 

[mdiehl]

One other solution may be the use of a "current relay" (if they are still available). A current relay is/was a standard relay that essentially had the entire load current of whatever you are running thru a heavy control coil which then operated a set of contacts. The contacts would then be used to monitor the "state" of the coil Load.
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