re telephone on hook off hok ok circuit tony kidson tony morgan demon co uk wrote in article ohzs b w w k qwb lonestar org lrk k qwb lonestar org writes mcovingt aisun ai uga edu michael covington writes in article ptolq p e werple apana org au petert zikzak apana org au peter just a thought of mine here since an on hook line is aprox v and off hook it usually drops below how about an led in series with a zener say around v on hook led on off hook led off would this work if anyone tries tried it please let me know aye there s the rub if you draw enough current to light an led the equipment at the phone company will think you ve gone off hook in the on hook state you re not supposed to draw current which means you should just use your digital voltmeter you can use an old vom but the phone company equipment can detect that and might think there s something wrong with the cable look guys what s the problem here if you want a light that goes on when the phone is off hook all you need it to run it in series with the line as i mentioned in my previous post if you want a light that goes on when the phone is on hook all you need is a voltage threshold detector if you re going to do the series diode thing which is the easiest just make sure that the led can take the current i can t recall it off hand but it s something like ma or more greggo greg moffatt moffatt bnr ca bell northern resarch inc ottawa canada my opinions not bnr s
