Voice activated switch

I'm trying to make a small circuit that emits a sound that is annoying
to a barking dog but can't be heard by people (This is for my dog, to
get him to stop barking at the neighbor's children). So I guess I have
a few questions:

1. I've heard that 25-35 KHz is the ideal range to try with dogs, so
what kind of speaker would I need to buy? Should I just look up any
small speaker that has that range and try that? I would obviously have
to see if it had any effect on the dog before I built the rest of the
circuit, so it would have to have a range of around 30-40 feet and moderately loud.

2. I'm thinking of using a Voice activated switch such as
https://www.electronics-lab.com/projects/sensors/025/index.html . A
dog's bark can be up to 105db I have read. Good idea? bad idea?

Thanks.

The special old Motorola IC has not been made for many years.

A speaker is driven by a power amplifier.
Most speakers have trouble above 5kHz. Many tweeters are very fragile and don't go above 17kHz.
Old guitar speakers had a piezo tweeter that goes up to 20kHz and maybe higher. The piezo tweeters are still available.

Of course such ultrasonic bark preventers are commercially available in many pet stores. Or do you just prefer to build your own?

Don't they just give the dog a shock (high voltage jolt) if it barks?

Sorry for pushing up this old topic, but I want to do the same and there wasn't too much discussion about this.

I am still in the "collecting information stage". A few things I found out before I asked my question:

• A high pitch noise may stop a barking dog
• Dogs don't like the 20-30KHz range
• I have some speakers that give me 100dBa at 25KHz (and go up to 50KHz)
• I like to use a simple 555 based sound generator to find the right frequency
• It will not work on all dogs (never mind that)
• I know that there are solutions on the market, still........

The sound output circuit should be no problem.

But I like to use the barking as a trigger. Therefore I like to get some ideas how to analyze an incoming sound and filter out not-barking noises.

circe said:

• A high pitch noise may stop a barking dog

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many dogs bark at a high pitched noise.

• Dogs don't like the 20-30KHz range

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Old gogs cannot hear high frequencies like old people.

• I have some speakers that give me 100dBa at 25KHz (and go up to 50KHz)

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I doubt it. Most speakers barely go to 20kHz. Maybe you have a piezo "whistle".

But I like to use the barking as a trigger. Therefore I like to get some ideas how to analyze an incoming sound and filter out not-barking noises.

Click to expand...

Audio is audio. How will you detect a dog barking and not somebody hammering on a wooden fence?

audioguru said:

How will you detect a dog barking and not somebody hammering on a wooden fence?

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This was my question. A dogs bark will be different from other noise. In google I can dictate text, so it is possible. The question was how.

Maybe you can use a computer with voice recognition software and the dog barking is a voice.
But maybe it will detect the barking from only one dog.

audioguru said:

Maybe you can use a computer with voice recognition software and the dog barking is a voice.
But maybe it will detect the barking from only one dog.

Click to expand...

Google speech-to-text works as long as it's spoken clearly and the background noise is not too high. A demo of the google online translation app in a bar failed.

But there could be different approaches. Sound spectrum analysis could be complex (= expensive). A simple 'clap switch' could be used based on a sound-silence sequence. A dog will usually bark several times with a few 10ms silence inbetween.

I think I go from there for now.....

PS: After a bit of googleing, I think NJU 7507 could be used as a sound analyzer:
**broken link removed**