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HP Forum Archive 17

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HP97 fault
Message #1 Posted by Michael Tortorella on 11 Sept 2007, 4:22 p.m.

Greetings, all: recently acquired 97, has fault as follows. Display seems normal, all numbers can be entered from keypad in usual way and they display correctly. But pressing "Enter" or any other key besides a number causes display to read "Error" and a tone to sound which cannot be removed except by powering down. I beg you to tell me this is not fatal, and would appreciate any hints on how to solve this problem. BTW, power supply is OK, machine does this even when operated on external power. Thanks in advance for any help. Mike T.

      
Re: HP97 fault
Message #2 Posted by Etienne Victoria on 11 Sept 2007, 4:48 p.m.,
in response to message #1 by Michael Tortorella

Put the printer mode selector on "MAN" and try again.

Let us know the outcome.

Etienne

            
Re: HP97 fault
Message #3 Posted by Michael Tortorella on 11 Sept 2007, 6:11 p.m.,
in response to message #2 by Etienne Victoria

Hello Etienne, I can't find the printer mode switch (if it's the unmarked button to the right of the printer paper roll, when I press it the tone comes on and the unit needs to be cycled off to make the tone go away). I do seem to be able to enter programming instructions OK (!?) Does this give you any clues? Thanks Mike

                  
Re: HP97 fault
Message #4 Posted by Walter B on 11 Sept 2007, 6:22 p.m.,
in response to message #3 by Michael Tortorella

Hi Mike, do you find the OFF-On switch? Then carefully look to the right: there are two more switches just 3cm away -- one for PRGM-RUN and another one above for MAN-TRACE-NORM. The latter is the printer mode switch.

HTH, Walter

                        
Re: HP97 fault
Message #5 Posted by Michael Tortorella on 11 Sept 2007, 6:45 p.m.,
in response to message #4 by Walter B

Hi Walter, Ah! In that case, the problem is present no matter what position the printer mode switch is in. Mike

                              
Re: HP97 fault
Message #6 Posted by Eric Smith on 12 Sept 2007, 11:25 a.m.,
in response to message #5 by Michael Tortorella

If an HP-97 is making noise, it's either a printer or card reader problem, since those are the only moving parts. If you've already tried disabling the printer (setting the switch to MAN - do this *before* it starts making noise, as in before you power it on), then most likely either the the printer mode switch is broken, or the noise is coming from the card reader (which would be due to a card reader switch being broken).

                              
Re: HP97 fault
Message #7 Posted by Etienne Victoria on 12 Sept 2007, 3:12 p.m.,
in response to message #5 by Michael Tortorella

Hi!

If the noise comes from the printer, it could be a malfunction of the reed switch and/or magnet telling the printhead it has reached the end of the line.

Then the printhead gets stuck at the eol and the printer motor keeps trying pushing it.

Is the printhead on the right side or on the left ?

Before trying something else, are we sure the noise doesn't come from the card reader ?

Etienne

Edited: 12 Sept 2007, 3:13 p.m.

                                    
Re: HP97 fault
Message #8 Posted by Michael Tortorella on 12 Sept 2007, 8:09 p.m.,
in response to message #7 by Etienne Victoria

I'll check the print head. However, it's not a "noise", it's a tone (about 700 Hz, I'd guess). It seems that it was intended to come on when "Error" shows on the display. Thanks Mike

                                          
Re: HP97 fault
Message #9 Posted by Eric Smith on 12 Sept 2007, 11:03 p.m.,
in response to message #8 by Michael Tortorella

There is nothing in the HP-97 that is intended to produce a tone. If it's making a tone, something is wrong that is causing unintended operation of the card reader or printer mechanisms. The "Error" display is a result of the firmware recognizing that one of those mechanisms is misbehaving.

                                                
Re: HP97 fault
Message #10 Posted by michael tortorella on 14 Sept 2007, 11:15 p.m.,
in response to message #9 by Eric Smith

Hi Eric, thanks, that makes some sense. I'll dig into it and see if there's anything hanging up the printer or reader. - Mike

      
Re: HP97 fault
Message #11 Posted by Eric Smith on 12 Sept 2007, 11:28 a.m.,
in response to message #1 by Michael Tortorella

Quote:
BTW, power supply is OK, machine does this even when operated on external power.

Applying external power via the charger is NOT necessarily sufficient. The printer requires more power than the charger can provide, and depends on having a good, charged battery.

While a charged battery pack should measure around 5V, a battery pack that measures around 5V with no load is not necessarily good.

            
Re: HP97 fault
Message #12 Posted by Michael Tortorella on 12 Sept 2007, 8:08 p.m.,
in response to message #11 by Eric Smith

Hi Eric, the external power is coming from a 5V, 30A supply. Should be enough current. Thanks, Mike

                  
Re: HP97 fault
Message #13 Posted by Chan Tran on 13 Sept 2007, 4:46 p.m.,
in response to message #12 by Michael Tortorella

It seems that it tried to print but the printer is defective. However, why does it want to print if the printer switch is in MAN position.


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