Telephone Timer

This sounds like a Big Brother device. Generally the best thing for a teenager is parental supervision. The problem with most teenagers these days is that they are on a cell phone all the time. I would imagine if you looked through enough cell phone models you could find one with calling limits. For the home phone you could design something fairly easily that detects time off the hook - no reason to time from the actual time the call went through. Just remember that if you also use the phone it's going to hang up on your mother-in-law when your wife uses it :)

Don't you call that a feature ?:-)

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

No, unless it only disconnects YOUR end of the line and blast the old lady with a freon air horn, then disconnects from the line. A second useful feature would be a manual disconnect button, for those idiots who ignore the 'Do not call' list.

When kid makes call, set kitchen timer to 29 minutes. When timer times out, go to kid's room, inform kid, "Ohe Minute To Go." Return to kitchen, set timer to 1 min. When timer times out, go to kid's room, say, "Time's up", and if the kid doesn't comply, take the telephone away.

This is called "parenting".

Good Luck! Rich