HP Forum Archive 07

[ Return to Index | Top of Index ]

BAT message Message #1 Posted by trey on 12 Feb 2002, 10:36 a.m. My BAT notice is on and stays on after I have replaced the batteries. Any suggestions?

Re: BAT message - Which calc... Message #2 Posted by Vieira, Luiz C. (Brazil) on 12 Feb 2002, 11:54 a.m., in response to message #1 by trey ... is yours? I have once experienced this with an HP41CV. One of the four batteries were placed in reversed position. In this particular case, the BAT annunciator remained "lit". I suggest (you have probably done it) also check for batteries voltage (multimeter or voltmeter). Cheers.

Re: BAT message - Which calc... Message #3 Posted by trey on 12 Feb 2002, 12:45 p.m., in response to message #2 by Vieira, Luiz C. (Brazil) it was one battery in the wrong direction. Thanks a ton

Re: BAT message - Which calc... Message #4 Posted by Tony Duell (UK) on 12 Feb 2002, 8:34 p.m., in response to message #2 by Vieira, Luiz C. (Brazil) I had this fault recently on a halfnut HP41 (actually a CV, but that's not important). I knew it wasn't a battery problem as it remained even when I connected a bench PSU to the battery terminals. I thought it was probably a fault on the display hybrid, but when I took the machine apart I found a dry joint (bad soldered connection) on a diode. If you look at the halfnut PCB, there 2 diodes one on top of the other on the left side. The top one seems to be an afterthought -- the cathode lead is soldered to a piece of red wire that goes across the PCB. The anode lead is soldred to the anode lead of the other diode. It was that connection between the 2 anode leads that was faulty. Without that connection, the display hybrid didn't get to sense the battey voltage, I guess.

[ Return to Index | Top of Index ]

Go back to the main exhibit hall