smallest lightest beeper

[Blarg]

where can I find parts to make a beeper/tone generator that weighs less than
a gram? I know the parts exist
in nearly every electronic watch (e.g. watch alarms), but I cannot find
anything under a half inch diameter.

 

[mike]

where can I find parts to make a beeper/tone generator that weighs less than
a gram? I know the parts exist
in nearly every electronic watch (e.g. watch alarms), but I cannot find
anything under a half inch diameter.

If you only need one, it's probably cheaper to buy a watch than to buy
one mail order, pay minimums + shipping.
You might want to firm up your specs. First you talk about weight, but
then you need size too. What else? Efficiency? Sound level? Frequency?
mike

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[Blarg]

good points. The output specs for my purposes need not be precise, just
audible from 10-20 feet away with normal human ears.
I need more than one. Potentially hundreds or even thousands. That's why
I've been asking about where to get the parts for a watch
alarm. In terms of size, the smallest possible. The smallest that exist.
Sizewise, I have tone emitting transducers that measure 1cm by 1cm, but I
know there are much smaller beepers. I just can't seem to find anyone that
has even a clue as to how to get the components/circuit.

 

[Jeff]

Look at this. I remember seeing this from when I was researching a part for
a product. They advertise it as "The World's Smallest Audio Transducer"
http://www.starmicronics.com/components/components_pages/prod_series/nft_series.html

Jeff

 

[mike]

good points. The output specs for my purposes need not be precise, just
audible from 10-20 feet away with normal human ears.
I need more than one. Potentially hundreds or even thousands. That's why
I've been asking about where to get the parts for a watch
alarm. In terms of size, the smallest possible. The smallest that exist.

I understand where you're coming from, but specs like "smallest
possible" are simply not helpful.
Would you pay $50 more each to make 'em a millimeter smaller?
If you would, I've got a grinder and some free time ;-)

At the risk of sounding like a soapbox...
The ABSOLUTE MOST IMPORTANT PART OF A PROJECT IS THE SPECIFICATION!!!
Many project problems can be traced directly back to poor specification.

If you approach a vendor with a statement like, "just
audible from 10-20 feet away with normal human ears"...
An excellent vendor will ask, "What does that mean?"
A typical vendor will try to sell you something.

By "just audible," do you mean "barely perceptible?" Probably not...
but I can't tell. You're too close to the problem. You have
preconceived notions that are different from mine. You know what you
meant, I heard what you said, but communication didn't happen.

Getting down off the soapbox,
Sound is all about air pressure. If the transducer is smaller, it needs
to have more displacement. Depending on the frequency, it might be
quite directional. Think about ways to increase the coupling to the
air. Resonance with the packaging can be your friend.
Do some research on horn loudspeakers. There's been some interesting
research on vibrating the plastic case on computers to produce sound.
MIT Technology Review...I think...is where I read it.
mike

Sizewise, I have tone emitting transducers that measure 1cm by 1cm, but I
know there are much smaller beepers. I just can't seem to find anyone that
has even a clue as to how to get the components/circuit.

--
Return address is VALID but some sites block emails
with links. Delete this sig when replying.
..
Wanted, PCMCIA SCSI Card for HP m820 CDRW.
FS 500MHz Tek DSOscilloscope TDS540 Make Offer
Wanted 12" LCD for Compaq Armada 7770MT.
Bunch of stuff For Sale and Wanted at the link below.
MAKE THE OBVIOUS CHANGES TO THE LINK
ht<removethis>tp://www.geocities.com/SiliconValley/Monitor/4710/