The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

Are they susceptible to damp in the air? My guess would be they were
designed not to be, since they're common on kitchen appliances. or perhaps
once were.

--
*Stable Relationships Are For Horses.

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...

The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

Are they susceptible to damp in the air? My guess would be they were
designed not to be, since they're common on kitchen appliances. or perhaps
once were.



Mallory 'Sonalert' were the originals - robustly made with encapsulated
electronics - quite pricey. I've just replaced one on my Benford single drum
vibrating roller with an eBay £2.50 jobby that seems to do all that is asked
of it and has the exact same mounting requirements as the Mallory type which
I've been familiar with since the late 1960's

Andrew

Dave Plowman (News) brought next idea :
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

The ones which work on a DC supply, have a built in oscillator, some
are just the sounder, needing an external oscillator.

In article ,
Harry Bloomfield wrote:
Dave Plowman (News) brought next idea :
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

The ones which work on a DC supply, have a built in oscillator, some
are just the sounder, needing an external oscillator.

Yes. The one in question has that built in oscillator, so works from plain
DC.

Basically, it's gone intermittent for no apparent reason I can find.
Sometimes bleeps, sometimes just clicks. Could be a dry joint in the
electronics, but does seem to depend on the weather.

--
*Therapy is expensive, poppin' bubble wrap is cheap! You choose.

Dave Plowman London SW
To e-mail, change noise into sound.

On Monday, 4 June 2018 16:30:14 UTC+1, Dave Plowman (News) wrote:
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.
Are they susceptible to damp in the air? My guess would be they were
designed not to be, since they're common on kitchen appliances. or perhaps
once were.

A quick google suggests that Rochelle salt piezo crystals can be affected by moisture. They can even be used as humidity sensors.

Owain

Some tend to die for no apparent reason. Most are a pietzo device in the
main I think. Very cheap as chips, but you need the right voltage one. Often
find them in old computers.
Brian

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"Dave Plowman (News)" wrote in message
...
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

Are they susceptible to damp in the air? My guess would be they were
designed not to be, since they're common on kitchen appliances. or perhaps
once were.

--
*Stable Relationships Are For Horses.

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Harry Bloomfield wrote:
Dave Plowman (News) brought next idea :
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

The ones which work on a DC supply, have a built in oscillator, some
are just the sounder, needing an external oscillator.

Yes. The one in question has that built in oscillator, so works from plain
DC.

Basically, it's gone intermittent for no apparent reason I can find.
Sometimes bleeps, sometimes just clicks. Could be a dry joint in the
electronics, but does seem to depend on the weather.

Dry joints can be weather sensitive. Seen with phone street cables.

On Monday, 4 June 2018 19:00:31 UTC+1, Dave Plowman (News) wrote:
In article ,
Harry Bloomfield wrote:
Dave Plowman (News) brought next idea :
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.

The ones which work on a DC supply, have a built in oscillator, some
are just the sounder, needing an external oscillator.

Yes. The one in question has that built in oscillator, so works from plain
DC.

Basically, it's gone intermittent for no apparent reason I can find.
Sometimes bleeps, sometimes just clicks. Could be a dry joint in the
electronics, but does seem to depend on the weather.

I've brought sounders that have a bit of tape over then that you remove after soldering and washing (for automated process).
I don;t think there's an officail technical differnce for whether an device can be referred to as a buzzer or sounder, then there's Piezo transducers that we use either to make sound or used as a simple microphone to sense vibrations.


--
*Therapy is expensive, poppin' bubble wrap is cheap! You choose.

Dave Plowman London SW
To e-mail, change noise into sound.

on 05/06/2018, whisky-dave supposed :
I've brought sounders that have a bit of tape over then that you remove after
soldering and washing (for automated process).
I don;t think there's an officail technical differnce for whether an device
can be referred to as a buzzer or sounder, then there's Piezo transducers
that we use either to make sound or used as a simple microphone to sense
vibrations.

I would call a buzzer one of those electro mechanical devices, with
contacts which make and break, like an old fashioned bell, but lacking
the dome/ bell.

On Monday, 4 June 2018 20:01:03 UTC+1, wrote:
On Monday, 4 June 2018 16:30:14 UTC+1, Dave Plowman (News) wrote:
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.
Are they susceptible to damp in the air? My guess would be they were
designed not to be, since they're common on kitchen appliances. or perhaps
once were.

A quick google suggests that Rochelle salt piezo crystals can be affected by moisture. They can even be used as humidity sensors.

Owain

they can indeed. Of course no piezo disc uses rochelle salt.


NT

On Tuesday, 5 June 2018 11:06:10 UTC+1, Harry Bloomfield wrote:
on 05/06/2018, whisky-dave supposed :
I've brought sounders that have a bit of tape over then that you remove after
soldering and washing (for automated process).
I don;t think there's an officail technical differnce for whether an device
can be referred to as a buzzer or sounder, then there's Piezo transducers
that we use either to make sound or used as a simple microphone to sense
vibrations.

I would call a buzzer one of those electro mechanical devices,

I don't think that is how they are classified.

https://www.amazon.co.uk/Cylewet-Ele...eywords=buzzer


https://www.rapidonline.com/catalogu...h?Query=buzzer


with
contacts which make and break, like an old fashioned bell, but lacking
the dome/ bell.

but that isn't how piezo devices work and the vast majority of them are called buzzers.

Are speakers electro-mechanical .
when a student asks me for a buzzer, sounder, speaker, or piezo or transducer I always ask them what they want it for before I'll supply one to them.
Unless it;s on their list of parts then I order what they have asked for usually.

On 05/06/2018 11:21, wrote:
On Monday, 4 June 2018 20:01:03 UTC+1, wrote:
On Monday, 4 June 2018 16:30:14 UTC+1, Dave Plowman (News) wrote:
The sort of smallish round sounder you get in myriads of things that
bleep. Just fed with DC and produce that bleep.
Are they susceptible to damp in the air? My guess would be they were
designed not to be, since they're common on kitchen appliances. or perhaps
once were.

A quick google suggests that Rochelle salt piezo crystals can be affected by moisture. They can even be used as humidity sensors.

Owain

they can indeed. Of course no piezo disc uses rochelle salt.


NT


what do HGVs use as reversing warnings ?. They are exposed to
all manner of weather, salt and crap.