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Bob Shuman[_2_] Bob Shuman[_2_] is offline
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Default GE 26920 Cordless Phone - Battery Does not charge

You need to know the proper current limiting resistor value. It sounds to
me as though 150 ohms is still possibly too high. If you measure the
voltage drop across that resistor, you can determine the charging current.
Compare that to the suggested charge rate for the 3.6V battery pack and then
adjust the resistor accordingly. I do not believe it is a defective battery
pack, so would not purchase another replacement till you determine that it
is receiving the correct charging current.

It is possible that the original resistor could have burned up over time if
you had a dead shorted battery pack. I'd do with a higher calculated
maximum wattage (assuming the full DC supply voltage gets dropped across
that resistor) just to be sure this does not happen next time around.

Good luck. Your use of the English language is very good.

Bob

"MP" wrote in message
...


For last few hours , been working on this task. Here are some more
findings.

1. The burnt resistor was showing 330Ohms on my DMM. I shunted it
with another 140 Ohms resistor. Put a LED across the handset
charge terminals of the base unit. Bingo !!! the base unit Charge/
In-use LED light's up......... so basically it may be that the
original value of the resistance was around 150Ohms but due to heat,
this got bumped to 330Ohms ( wild guess :-) )
The LED was drawing about 35mA of current


2. Now, instead of the LED, I wired the handset, connected the
battery ( 3.6V, 300mAH) to the battery terminals on the handset
PCB.
The charge/in-use LED of the base unit lit up........ but after
about a minute, the LED of the base unit is no more on...
Removed the battery, measured the terminal voltage and it show's
3.6V but a little bit usage ( by pressing talk button on the
handset) drops it to 2.2V
The battery pack is brand new and not a old one so I cannot doubt the
battery.


3. I repeated the step 1 and the LED of base unit is on again...

4. So basically, I still have not fixed this instrument. How can
the battery voltage jump to 3.6V in just a minute ? Should it not be
gradually increasing ( sorry, its been a while i have handled
batteries so a bit rustic). why does the base unit LED turns off in
a minute ? When this instrument was brand new, i remember this used
to remain on as long as the handset was kept on the base unit.

5. I am going to buy one more brand new battery set and try the
above steps again just to be sure that the battery is not the culprit.


Note: Yes, English is not my mother-tongue but its the language I
have used in my profession for last 20 years. Any more grammar errors
are welcome :-)