Hi, I hope this isn't too trivial a question for an electronics board, but I'm trying to modify my Nokia 6230 phone in two ways, and could do with a bit of help please.
1. I want to add an on-off switch to disconnect the aerial (for the network, I mean), which I don't see as possible in the menus. I partly want to do this to stop worrying about the possible health risks if I have it on me all the time (I never know whether to believe the stuff about radiation from phones), and partly to save battery power when I'm on ultra-light trekking excursions. I don't want to have to switch the phone on and off, because I like to use it for its calendar functions, camera, mp3 player, radio, and voice recorder. I don't get many calls on it, so just want to connect to the network occasionally to check for texts or missed calls.
What I want to know is
a) whether when it's switched off the aerial will not be giving off microwaves or whatever it is that's thought to have health risks associated with it.
b) whether all I have to do is interrupt the central pin (a little sprung telescoping connection post) of the three that connect the aerial to the phone front. I've had the aerial unit out and put a piece of insulation between each connector to test what happens, and only the central one causes the phone to lose signal, but I don't know if that means the aerial is (or aerials are) disconnected, or if it's just that the data line is the middle pin so it's not reporting a signal while the aerial(s) are still working. I know very little about electronics, but I think I remember that aerials in radios don't have two connections, just one. I also remember reading that this phone is set up to work on two different protocols or something, so it just occurred to me that each might be powered by the other two pins. Unfortunately, I can't read the schematics I've found (links when I've got permissions if anyone wants them). It would be easy from there if it's just a case of soldering two connections to the correct (single) pin and its locator on the phone body (well, I say easy, it'll take some doing getting the wire in there and soldered!) with insulation between and running the wires to a switch on the body, a lot less easy if I have to do it with more than one and install a double-pole switch (or whatever that's called).
2. I've taken a solar-powered torch apart because the battery has died, and thought it would be handy to fit the solar panel on the back of the phone connected to the battery connection points (the sprung metal bits that contact the battery connections I mean). I'm not expecting miracles from it, but hoping it might just extend the battery life by trickle charging it when left on a windowsill. Again, I'm puzzled because the battery has three connections and, although the outermost two are marked + and -, I have a feeling that the middle one might be powering a different circuit in the phone, or might even be a separate cell inside the battery.
a) Do you think I can just connect the solar cell across the outer two? The battery is BL-5C 3.7V (adaptor gives 5.7V at 800mA). I've measured 1.4 mA across pins 1 and 3 in the phone when the charger is connected and 0.15 mA across 1 and 2.
b) Why does it have three contacts?
My usual method is just to try things and see what happens, but I thought I'd ask before ripping into it this time. There's not much room for a swtich, but I'm thinking the little "window" above the IR receiver/transmitter is nothing more than a hole to let the speaker volume through and I could fit a little ultra-micro type switch there. The solar panel should go on the back very nicely. People will think, as usual "My word, what a rubbish old phone that guy....hey, wazzat? It's got a solar panel on it!"
1. I want to add an on-off switch to disconnect the aerial (for the network, I mean), which I don't see as possible in the menus. I partly want to do this to stop worrying about the possible health risks if I have it on me all the time (I never know whether to believe the stuff about radiation from phones), and partly to save battery power when I'm on ultra-light trekking excursions. I don't want to have to switch the phone on and off, because I like to use it for its calendar functions, camera, mp3 player, radio, and voice recorder. I don't get many calls on it, so just want to connect to the network occasionally to check for texts or missed calls.
What I want to know is
a) whether when it's switched off the aerial will not be giving off microwaves or whatever it is that's thought to have health risks associated with it.
b) whether all I have to do is interrupt the central pin (a little sprung telescoping connection post) of the three that connect the aerial to the phone front. I've had the aerial unit out and put a piece of insulation between each connector to test what happens, and only the central one causes the phone to lose signal, but I don't know if that means the aerial is (or aerials are) disconnected, or if it's just that the data line is the middle pin so it's not reporting a signal while the aerial(s) are still working. I know very little about electronics, but I think I remember that aerials in radios don't have two connections, just one. I also remember reading that this phone is set up to work on two different protocols or something, so it just occurred to me that each might be powered by the other two pins. Unfortunately, I can't read the schematics I've found (links when I've got permissions if anyone wants them). It would be easy from there if it's just a case of soldering two connections to the correct (single) pin and its locator on the phone body (well, I say easy, it'll take some doing getting the wire in there and soldered!) with insulation between and running the wires to a switch on the body, a lot less easy if I have to do it with more than one and install a double-pole switch (or whatever that's called).
2. I've taken a solar-powered torch apart because the battery has died, and thought it would be handy to fit the solar panel on the back of the phone connected to the battery connection points (the sprung metal bits that contact the battery connections I mean). I'm not expecting miracles from it, but hoping it might just extend the battery life by trickle charging it when left on a windowsill. Again, I'm puzzled because the battery has three connections and, although the outermost two are marked + and -, I have a feeling that the middle one might be powering a different circuit in the phone, or might even be a separate cell inside the battery.
a) Do you think I can just connect the solar cell across the outer two? The battery is BL-5C 3.7V (adaptor gives 5.7V at 800mA). I've measured 1.4 mA across pins 1 and 3 in the phone when the charger is connected and 0.15 mA across 1 and 2.
b) Why does it have three contacts?
My usual method is just to try things and see what happens, but I thought I'd ask before ripping into it this time. There's not much room for a swtich, but I'm thinking the little "window" above the IR receiver/transmitter is nothing more than a hole to let the speaker volume through and I could fit a little ultra-micro type switch there. The solar panel should go on the back very nicely. People will think, as usual "My word, what a rubbish old phone that guy....hey, wazzat? It's got a solar panel on it!"