and still I don't remember the details.
Why don't you try and pick up the 15kHz with some microphone OP and filter,
a comparator, I think this would do the trick without lot's of problems.
Friedel
At 12:34 30/08/03 -0800, you wrote:
I need to turn on a couple of small security monitors when a TV is turned on. In the past, they made a gizmo for the early personal computers that turned on the monitor, printer, etc. when the computer was turned on by sensing the current being drawn by the computer. I have not seen them for years.
It would be trivial to open the TV and find some voltage in there only present when it is on and let it activate a relay, but when the TV dies, I would have to go through the procedure again. A universal device with a plug-in for the TV would be nicer, and would not require cracking open the TV. I think modern TVs draw a little line current all the time, so this thing would have to distinguish between a fraction of an amp, and the higher draw when the TV is actually on.
Any suggestions for a simple circuit? Or is there a commercial product that will do the job?
Thanks in advance.
Syd H. Levine
AnaLog Services, Inc.
Phone: 270-276-5671
Telefax: 270-276-5588
E-mail: [EMAIL PROTECTED]
URL: www.logwell.com
