Planix 7 Battery Problem

[jaselbig]

Hello Everyone,

Electronics newbie here, recent mechanical engineering graduate but got into electronics while I was in school.
I just got a Planix 7 planimeter (what is a planimeter? http://www.tamaya-technics.com/e_site/planix567_e.html) that doesn't work. Here are the symptoms:
-Turns on with AC adapter connected and battery removed
-Doesn't turn on with AC adapter connected and battery installed

How should I go about troubleshooting this?
I would suspect something is wrong with the charging circuit? The battery connects to the blue and green wires.


Here are some screenshots of the board:
http://www.flickr.com/photos/97850427@N06/sets/72157634249684009/

[CompElitePC]

I would start with testing TR1 and TR2 (TR1 is PNP and TR2 is NPN)  test TR2 and transistor 54ALR  first. 

one question: will it power up with battery and no AC adapter?

[David_AVD]

What type of battery?

[CompElitePC]

What type of battery?

should be 4.8v nicad

[David_AVD]

Could the problem be as simple as a dead (partially shorted) battery pack dragging the system down?

[CompElitePC]

Could the problem be as simple as a dead (partially shorted) battery pack dragging the system down?

possible.. checking a battery is simple enough, i imagine its been checked already??
i personally think a transistor isnt switching over.