HP Forum Archive 08

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broken 'speaker' HP41C Message #1 Posted by Peter Vanderpoorten on 22 June 2002, 4:46 p.m. The speaker of my 'old' HP41C has broken... Where can I find such a speaker or what type could I buy in an electro-shop? Maybe that's the reason why I lose all my battery-power in about two weeks.

Re: broken 'speaker' HP41C Message #2 Posted by Hans Brueggemann [GER] on 23 June 2002, 1:34 a.m., in response to message #1 by Peter Vanderpoorten peter, the broken speaker is called a 'piezo-element'. you can find these in electronic stores and online-shops (for example www.conrad.de ). the price is something between 50c and 1 eur. cheers, hans

Re: broken 'speaker' HP41C Message #3 Posted by Ellis Easley on 23 June 2002, 2:45 a.m., in response to message #2 by Hans Brueggemann [GER] There are at least two types: two wire and three wire. The third wire is for feedback, so the element can be used at its resonant frequency (the response is quite sharp). The 41 only needs the two wire.

Re: broken 'speaker' HP41C Message #4 Posted by David Smith on 23 June 2002, 3:46 p.m., in response to message #1 by Peter Vanderpoorten Your battery life problem is almost certainly NOT related to your beeper problem. Most likely cause of short battery life is a leaky main power supply capacitor (one of the two big electrolytic units near the upper left hand side of the fullnut CPU card).

Re: broken 'speaker' HP41C Message #5 Posted by John Robinson on 25 June 2002, 2:28 a.m., in response to message #1 by Peter Vanderpoorten What about trying the speaker in one of those annoying musical greeting cards. They look the same, therefore it must be the same !. At least it will kill one of those lame cards.

Re: broken 'speaker' HP41C Message #6 Posted by David Smith on 25 June 2002, 1:14 p.m., in response to message #5 by John Robinson It is certainly worth a try. You might also try Radio Shack. I think they have small piezo beeps enclosed in plastic. Most modern piezo elements have a feedback (third) connection that the HP units do not have. The mounted ones also include a transistor and some associated drive circuitry. I don't know how well they would work in the HP machine though. But on over 100 '41 sereis machines I have found never found a bad beeper. They are very rugged. About the only way to kill them is with a too hot soldering iron. Speaking of which, did you inspect the leads to the piezo element? They are very thin and fragile (especially in the halfnut machines) and like to break at the solder joints.

Re: broken 'speaker' HP41C Message #7 Posted by Peter Vanderpoorten [BEL] on 29 June 2002, 6:25 p.m., in response to message #6 by David Smith Thanks everyone for the tips. (The element itself is broken due to a dropdown, the toplayer is fallen into pieces)

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