Mobile 'phones generally do too much and it has been suggested here that their functions should degrade gracefully as the batteries drain. I want to go a bit further with this, but don't know if it's feasible.

A mobile 'phone should be attachable to a landline telephone socket. On attachment, the 'phone should behave like an old-fashioned no-frills landline telephone, with the appropriate number for the line, no voicemail, caller display or anything else, just like a traditional 'phone except for not being rotary dial. Whilom, the mobile number goes to voicemail.

Moreover, and here i don't know if this is possible, the trickle of power emerging from the socket which normally powers a basic landline 'phone recharges the battery on the mobile.

This would mean that a telephone line subscriber would only need one 'phone, they could recharge it (conceivably) even if there was no other source of electricity and it would prevent vendor lock-in by providing a standard power connector for the device.

Oh yes, and if there was no 'phone jack, it should be pedal-powered, e.g. it could be charged while cycling.

If this is M-F-D: echo or whatever, i'll just delete it.
-- nineteenthly, Jul 12 2008

From this Cell_20phone_20_22b...0by_20low_20battery
My inspiration [nineteenthly, Jul 12 2008]

Interface Circuits http://www.epanoram.../teleinterface.html
Bunch of good info here. [Amos Kito, Jul 12 2008]

In order for two wires to do so much, a lot of tricky stuff happens (switching, etc.). If you pick up a phone receiver, the line will go dead after a time. If your equipment screws up phone company systems, they get angry. You won't like them when they're angry.

Be careful that your electrical equipment doesn't require more current than your power source provides. Off hook current is "20-50 mA". My cell phone charger is rated at 700 mA. The voltages are similar, except when the phone "rings". See [Link] for info about connecting things to telephone lines.

I think the charging part could work (if very slowly, and specially designed to simulate a wired phone). But if you're at a spot with an available phone port, you're often near an electrical outlet.

The land line part of the idea should work, except the phone may need some power even for that. And if you’re charging while talking, prepare for a very lengthy phone call.
-- Amos Kito, Jul 12 2008


Yes, i remember the bizarre "Prohibited" sticker thing on the modem kits, so i know not to annoy the GPO (as it was then). OK, so one way round that would be to have a 'phone number specifically for charging the 'phone, so it's a genuine call, either 0800 or not, but not a genuine caller at the other end. If that were so, what if it were a very loud tone played down the line? Would that provide more power? You would actually then be paying the 'phone company to charge your 'phone, and i imagine they might be quite keen on that if you spoke to them nicely.

Haven't checked the link yet, but thanks.

OK, checked it now and there's a lot of info there. In the meantime though, how about a basic mobile 'phone which only makes and receives calls anyway, so lower power consumption, useable as a landline and which "steals" some of its charge by reducing the sound volume on the incoming sound and also nicks a bit of energy from the sound of the caller's voice. Then, at the same time, it soaks up power through motion and photovoltaics, so carrying it around and leaving it in the sun charges it as well. I suppose that would make the charge from the line itself quite unimportant. Then again, a charger with a 'phone jack plug at the other end wouldn't be relevant to the 'phone company, would it? The idea being to use either and provide a standard for chargers.

An afterthought. If you also routed faxes through it and used it as an acoustic coupler, that would help charge it, assuming a serious lack of broadband internet of course.
-- nineteenthly, Jul 12 2008



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