🚀 go-pugleaf

In article <13284@life.ai.mit.edu> campbell@.ai.mit.edu writes:

   charge pumped device (DC-DC charge pumped devices, there are lots of these
   listed at +/-48 volts in the catalogs I have).

I'm wondering if you intend to draw power from the telephone line when 
it's on-hook (meaning, not being used). The on-hook DC resistance of
any device you connect to the telephone line  should be more than 
5 Meg ohms. 5M gives you a ringer equivalence number of 5, which is the
maximum permissible, meaning you cannot have any other device on the
line. (REN measures how much DC and AC load you impose upon the telephone
line. Common phones have a REN of 1.0. FCC limits you to a maximum of
5.0 when you add up all the devices connected to that line. )

   1. Will this work? I'm not entirely sure so the only way to tell is to
   experiment.

I've seen ads for laptop modems that are line  powered, so it's doable. 
After you've picked up the line, you can draw a fair amount of DC 
power from the line : usually there's 20 - 25 mA at about 8V. 

Regards, 

/ Jon Sreekanth

Assabet Valley Microsystems			Fax and PC products
346 Lincoln St #722, Marlboro, MA 01752		508-562-0722
jon_sree@world.std.com