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1bigdog
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Join Date: Jan 2010
Posts: 1

LED for Phone Line

01/27/2010 12:02 AM

I need a circuit to power a LED from telephone line voltage indicating that the phone line is connected to the circuit. It must meet FCC guidelines. Off hook voltage is 8-12 vdc.

Any suggestions?
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madness
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Hobbies - CNC - New Member Hobbies - Musician - New Member

Join Date: Jan 2007
Location: South Africa Johannesburg
Posts: 187
Good Answers: 3
#1

Re: LED for Phone Line

01/28/2010 11:31 AM

Yes 3 to 4 diodes (1n4007) in series and back to back to create a voltage differential to power a led, likely to also require a resistor. Have purposely being vague as i don't know the FCC laws or the nature of the PTN in your country. I would think to investigate that first. You should also find other suggestions on the net.

Regards

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