|Re: Ex-NOS 41, battery compartment modified & ROM?|
Message #2 Posted by Reinhard Hawel on 2 May 1999, 6:39 p.m.,
in response to message #1 by Nick Hayes
I also got one calc from this lot. Mine works without any problems. The small thing in the entrance to the battery compartment is a so-called speed-up. The 41 powers up in fast mode (Try BEEP to hear the difference, should be about twice as fast as the original). If you tip onto the small point on this block, you change the speed. The block is a switch.
Don't try to remove it, you can't switch back into normal mode if you do that. You can change the speed doring operation of the calculator which indicates that the speed up is well done, more than just a switch and a inductivity or capacitor.
Maybe you should clean the battery contacts and remove the ROM. My contacts look excellent, but I remember having problems by inserting the batteries the first time. My pattery pack is somewhat hard to put in and out of the compartment (this is caused by the switch) but fits well. I never had problems with it since that first time.
My suggestion: Remove the batteries and the ROM. Let all of these lie some time (maybe days, but mostly some hours should be enough) without the batteries and then try to reanimate it by putting in new batteries. This will unload the internal capacities in the calculator and cause a complete reset. If the calculator works without the ROM, insert it again to check if the ROM is faulty. I power the 41 with NICADs and I'm rather sure it's a contact problem with the batteries or the module.
I also don't have any information about the ROM and I'm also interested in knowing something about it. I saw that the ROM takes and sets the 41 into USER mode when the machine is powered up. This is a common practice for custom ROMs.
Does your calc also have a green point between USER and PRGM keys?