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HP Forum Archive 02

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Help! HP 75D has lost its voice !
Message #1 Posted by Don Williams on 7 Mar 2000, 11:49 a.m.

Just disassembled an HP 75 D I recieved. The speaker is missing. Since I have no schematics, or the missing part, I'm not sure about what to use to replace it. Does anyone have a suggestion for a replacemant part ? Does anyone have a hopelessly dead 75D they would be willing to cannabilize ?

      
Re: Help! HP 75D has lost its voice !
Message #2 Posted by Viktor Toth on 8 Mar 2000, 5:00 a.m.,
in response to message #1 by Don Williams

Does the HP-75D have a voice? I thought its voice output is connected to an external jack?

Viktor

            
Re: Help! HP 75D has lost its voice !
Message #3 Posted by Don Williams on 8 Mar 2000, 10:22 a.m.,
in response to message #2 by Viktor Toth

There was some kind of speaker. About 1/2" diameter. The wires are just cut off on my unit, and hanging there. I do not know what type of speaker it was. There are some pictures, on this site, of the exposed circuit boards and one can see the speaker element, but that doesn't help me identify it.

                  
Re: Help! HP 75D has lost its voice !
Message #4 Posted by george on 8 Mar 2000, 11:48 a.m.,
in response to message #3 by Don Williams

The HP-75s not supplied in the accessory pod had a piezoelectric speaker element wired to one of the boards. 75s supplied in the pods didn't have the speaker - the wires were connected to a mini phone jack on the pod. The wires had to be cut to completely remove the 75 from the pod.

Probably any piezoelectric speaker element will work as a replacement (they should all behave in a similar fashion electrically). Radio shack used to sell one, though it may be physically too large. One about the right sized might also be cannabalized from a dead or cheap watch with alarm features.

Be careful when tightening the screws holding the back on. If they are overtorqued the plastic standoffs into which they screw may split, rendering that screw useless.

                        
Re: Help! HP 75D has lost its voice !
Message #5 Posted by Don Williams on 8 Mar 2000, 12:01 p.m.,
in response to message #4 by george

Thanks for the info. I'm on the right track again. I have the pod. I could relate a long story about testing the wand with a program that issued an audio prompt with a successful bar code scan, but that comedy of errors would be too embarassing for me to admit to. It taught me a few things about the 75D I didn't know before. Would rather have avoided the lesson though.


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