HP-67 Power trouble

[benitoprat]

Hi
If I turn off the Off/On switch and put it On again, the HP-67 doesn´t work. Npt a single dot appears.
If I remove the battery and put it on againwith the Off/On switch to ON it starts and works perfect, (even the Card Reader)

Please if someone knows how to fix this I would be very grateful

Best regards

[Michael de Estrada]

Try again with the AC adapter/charger plugged in. Could be battery not fully charged or poor battery connection. Also, could be dirty OFF/ON switch contacts.

[benitoprat]

Thank you for your answer. I tried with the AC adapter/charger plugged in and with a fresh charged battery (I have an external HP battery charger) and still have the problem.
Best regards Daniel

[Michael de Estrada]

There are others on this forum who have a greater knowledge of this, and may have some ideas. The only thing I can think of is that the capacitors that are used in the LED circuit may be weak, and although the calculator ICs are getting powered, the LEDs are not. Why removal and then re-installation of the battery pack fixes this I do not know. Then again, I could be completely wrong on this, so it is just idle speculation.

Edited: 7 July 2009, 9:52 a.m.