: 
: >
: >> In article <1ptolq$p7e@werple.apana.org.au> petert@zikzak.apana.org.au (Peter
: >> >
: >> >Just a thought of mine here:
: >> >Since an on-hook line is aprox 48-50V, and off-hook it usually drops below 1
: >> >How about an LED in series with a zener say around 30V.
: >> >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 100mA or more?)

Greggo.