Cmos battery in Micron Transpoet Trek 2

First time in quite awhile that I've posted, usually I just lurk and enjoy the tips and problem solutions I pick up here - hope you don't mind me posting from Google...

I think the battery is getting low in this older laptop, (circa 1997) and the main problem is that it's soldered to the motherboard. I can't see any markings on it and the solder blobs holding it are rather large (compared to any other solder joints on the board.

The battery is about 1/4 inch tall and about 3/8 inch in diameter, but shows no ID numbers as mounted, would any one happen to be familiar with this machine? I'm thinkinking of just adding a couple wires and mounting a battery somewhere else, if I can confirm that it is a 3 volt battery (it reads about 1.7 volts and the computer losses time pretty quick, several minutes every hour.

Thanks in advance for any ideas and /or information.

Mike Lightner

Reply to
mike
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Exactly the same as this PC I'm writing this on. 2 wires soldered to the existing , in place, soldered-in battery and a 3V battery wrapped up and stuck somewhere else. I forget what value of safety resistor I put in line , probably a about 10K

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

That's encouraging to hear - I guess these Transports (sorry 'bout earlier typo) are pretty durable machines. Safety resistor sounds good - I assume to protect the battery? how is it in the circuit?

Thanks muchly. Mike

Reply to
mike

The battery addition was successful, I used a CR2032 and the socket off a scrap MB, and put a 10K resistor in series with one of the wires

- found that that dropped the I-draw from about 50uA to around

30uA, and the laptop is now keeping the correct time again.

Thanks again, Mike

Reply to
mike

When I did that I could not be sure how the original battery would affect things, would it quickly drain the new battery? But I did that on this pc some years ago and the clock time still advances marginally, so presumed all ok.

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Reply to
N_Cook

I was kind of surprised that the current draw without the resistor was so low, but I wasn't monitoring the voltage at the same time so don't know if it was holding steady or not - at any rate, good to hear that it's apparently a long lasting repair.

Mike

Reply to
mike

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