|Re: Help with HP-42S|
Message #14 Posted by Mike Brady (San Francisco, USA) on 9 Nov 2003, 12:47 a.m.,
in response to message #1 by Steve in Seattle
I'm no expert, but I remember reading in the archives that when the HP-42S calculator goes into it's beeping mode, it can mean one of two things:
First: the calculator has a self protecting and anoying feature, as it sounds off automatically (beeping) warning you that my batteries are low and I need changing now! before I loose my continous memory and you loose your mind. Persistant little bastard thinks it's a smoke detector!!! Actually, when the calculator is off, it can detect a low-battery condition and an internal system flag is set which will make the calculator beep non-stop. So make sure you have some FRESH batteries handy, Silver Oxide batteries, i.e. Energizer's 357/303 also known as "357BP" or Duracell's D303/357B are best, or FRESH alkaline Duracell's PAX76A675AB also known as "76A" will do too. Also make sure the battery terminals are free of any corrosion or hand oils, handle the batteries by their edge, use a little alcohole and Q-Tip to clean the battery contacts and faces if you fingered them.
Any way: Resetting the Calculator is simple and it does not matter if the calculator is ON or OFF: Simply hold down the EXIT key while you press and release the SQUARE ROOT key once, then release the EXIT key. Repeat if necessary. That should stop the beeping and the display will show either "Machine Reset" in the top line's Y registry or in your case "Memory Clear", since it's been without power for a long time. Press the EXIT key to clear the display and your ready to go.
Also: If you unknowingly turned the calculator ON while the batteries were out, the calculator can misbehave. Remove the batteries and lightly press a coin against both battery contacts in the calculator for a few seconds. Put the batteries back in and turn ON the calculator. The display should say "Memory Clear". Reset the calculator as needed.
Second: is your calculator could have an open connection somewhere inside, maybe between the LCD and the PCB, and it will need servicing. One of the guys receintly posted his story of having to re-solder his do-it-yourself 32K memory chip exchange upgrade in order to stop his calculator from beeping, as he was not able to reset his calculator after his first soldering job. After re-soldering, he corrected an unknown bad solder connection and was able to get his calculator to comply with the above reset procedure.
I think the following is still valid.
You can contact Calculator Support:
1000 N.E. Circle Blvd.,
Corvallis, OR 97330, USA,
8:00 a.m. to 3:00 p.m. Pacific Time, Monday through Friday
Edited: 9 Nov 2003, 3:23 p.m. after one or more responses were posted