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HP Forum Archive 14

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HP 33C PR error
Message #1 Posted by Ronald on 10 Oct 2004, 4:18 p.m.

Hello,

I have a HP 33C (Spice) which give's an error "pr error".

The battery is fully charged. I switch it on. It is oké. Then you switch it off for 30 secinds and when you switch it on again it gives the above mentioned error. The other functions are 100%.

Any idea were to look for the make the memory again continious ?

Thank you

Ronald

      
Re: HP 33C PR error
Message #2 Posted by Thibaut.be on 11 Oct 2004, 4:10 a.m.,
in response to message #1 by Ronald

Are you sure that your battery pack is good ? You can try with 2 AA batteries (beware of the polarity) and connect them with a paper clip...

      
Re: HP 33C PR error
Message #3 Posted by Michel Beaulieu on 11 Oct 2004, 9:31 a.m.,
in response to message #1 by Ronald

I got this trouble on a HP-34C once after installing a power board coming from another calculator of that series without constant memory. Someone here explain me that these board looks the same but don't give power to memory when switch off.

I you donT' suspect that, it's perhaps a bad component on the power board... If the battery is ok at least...

            
Re: HP 33C PR error
Message #4 Posted by Ronald on 11 Oct 2004, 3:01 p.m.,
in response to message #3 by Michel Beaulieu

Hi,

The battery is fine, just rebuild and charged with a full 1600 MH NiMH battery.

The power board could be the case, I bought it as defective with some other stuff like keyus, chips, displays, the works, so It could very well be the board. I will make a check if the board make proper contacts.

Thank you.

                  
Re: HP 33C PR error
Message #5 Posted by Jon on 11 Oct 2004, 3:38 p.m.,
in response to message #4 by Ronald

Hi:

With 33C, 34C and 38C models it is important the position of the small ICs. I have some experience (not all have the same ICs). If you make me know the id. number I can check my notes. If they are in wrong position the calculator works but not the continuous memory.

Regards

Jon

                        
Re: HP 33C PR error
Message #6 Posted by Ronald on 11 Oct 2004, 4:40 p.m.,
in response to message #5 by Jon

Hi Jon,

I will open him tommorrow evening and take notes on the position.

Ronald

                        
Re: HP 33C PR error
Message #7 Posted by Ronald on 12 Oct 2004, 4:39 p.m.,
in response to message #5 by Jon

Hi Jon,

There is next to the large IC only one (1) small IC. marked with LB901, 79364, SGP 01. The mark on the IC is, if you look from the back with the display on top in left top corner.

Ronald

                              
Re: HP 33C PR error
Message #8 Posted by Tony Duell on 13 Oct 2004, 7:05 a.m.,
in response to message #7 by Ronald

It's possible there should only be one 8 pin chip (I believe there are several versions of some of these machines), but it _must_ be in the position closest to the display end of the calculator (and with the notch towards the display). On the -C models, the 8 pin chip nearest the display gets the backup supply to maintain continuous memory.

                                    
Re: HP 33C PR error
Message #9 Posted by Jon on 13 Oct 2004, 12:38 p.m.,
in response to message #8 by Tony Duell

Hi:

Just to confirm that Tony is right. My own 33C has only one 8pin IC.

Regards

Jon

                                          
Re: HP 33C PR error
Message #10 Posted by Ronald on 13 Oct 2004, 4:28 p.m.,
in response to message #9 by Jon

Yes, in my HP33C is only one small chip and is located closest to the display.

I think I have to look into more detail to the powersupply, maybe there is a broken line which shoul keep power to the memory chip. Do you have any idea to which pin of the chip the always present power is connected, so I back trace ?

Thank yoy


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