hp49g repair


Hi everybody !
I buy recently an new Hp49G on Ebay with "not power on" default.(ebay#802536491)
HP France (yes i'm French, sorry for my poor english)
does not repair unit not covered by warranty, so i have
only one choice: calculator into the trash or try to
repair myself (fortunatly i'm serviceman in mesuring equipment).
So after opening my hp49g (drill the 6 burned plastic spot in battery compartiment, the two half body are just clicked)
it's appair that the capacitor 1000µf 6v3 was dead (yes it's new !!)- i measure 1nF in my RLC Bridge. After remplacement by 470µF 6v3 Calculator works as new.
This capacitor is located a the right bottom of the
electronic board (the only one non CMS capacitor)
My calculator Serial number is CN11200858.
If you have trouble with your HP49g, try this repair solution and let me know the result...
Thanks to Hp museum for your fantastic works
Philippe from France


Hi, Philippe;

I read your post and I found it alot usefull.

Thank you for sharing this valuable info. I have an HP49G and I'll try your procedure, if needed.

Best regards.

Luiz C. Vieira - Brèzil


Thanks Luiz C.
The voltage across this capacitor is the battery voltage.
If when you push the on key, the voltage drop below 3volts
the capacitor is "tired" or dead.
With oscilloscope, no noise between +/- of this capacitor.
Regards from France

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