My landline phone comes with a lcd display caller id and clock.
Even if I remove the 2 AA 1.5V batteries, the lcd still shows time even if I'm not busy on a call.
The lcd has no other source of power as is turns off when I disconnect the line.
I'd like to power up a 1.5V quartz analog clock using the phone line.
Is that possible?
Any circuit suggestions welcome.
Thanks.
Edit:
The phone line has had no failures, at least since 2005, since they switched to fibre optic from copper wires.
And it's not illegal in India to connect low voltage devices like caller ID, tape recorders aka call recorders, answering machines and external ringers to the phone line, or so says the govt. owned company.
I'm crazy, officially:-P
But has anyone got circuit diagrams?
Best Answer
See Max current draw from a UK Phone Line? , Using a telephone cable to power up a light blub
You get up to 40ma at 50 volts, varying quite a lot when it rings. With a suitable buck converter you could probably power the clock, but it's not reccomended (and in some regions with state run telecoms may be illegal to connect unapproved equipment)