A simple query from a simpleton...
I have a cordless house phone, whose internal batteries are worn out. They are feeble 700mAh NiCads who hold their charge for only a few minutes' use now. Can I replace them with some 2100mAh Ni-MH's, of which I have loads (Recommended charge 7H 420mA)? Or will they not charge properly on the phone's base unit (Claimed output 9V 300mA)? And if not, should I just replace them with exact equivalent NiCads?
Thanks in advance.
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Brand and model of the phone?
If they fit, sure.
Hi Homer...
Oops, I'd like to respectfully throw in a caveat here, if I may?
If the phones charging contacts are at all exposed, then make durn sure that there's a rectifier *inside* the phone to limit current. Or, failing that, perhaps a very small resistor in series with the charging contacts.
Otherwise something external shorting them could produce horrible results. I'm thinking of putting the phone in a pocket with keys or loose change; or the youngsters tampering with it.
I'd also add that if the op goes this route that he seal the battery cover up somehow so that the kids can't "borrow" the batteries for their toys.
I admit to being a little prejudiced; I still have a five year old scar on my leg from one 1800 mah cell shorting in my pant pocket.
Take care.
Ken
Resistor?
Hi...
Sure, just a few ohms in series with the batteries would have virtually no effect while charging, but would severely limit current if they were inadvertently shorted?
Take care.
Ken
"rectifier" confused me.
Hi Homer...
Now I'm getting confused - not at all unusual :)
A rectifier in series with the battery pack so that it could charge from the external supply, but not discharge through the external charging contacts :)
Take care.
Ken
I'd use those 2100mAh jobs and give them a whirl. I can't think of any way you'll damage anything.
Graham
I have phones that can charge face up or face down.
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