Steve B wrote in
rec.crafts.metalworking on Sat, 29 Jan 2011 23:32:21 -0800:

I subscribed to some electronics newsgroups, but as of yet haven't passed
through their process to get messages.

In that case it's not a newsgroup. Perhaps you mean an online forum.

I want to build an ultrasonic dog repeller. I do real estate inspection,
and there are times that I encounter either obnoxious dogs or aggressive
dogs. I carry pepper spray, and have almost had to use it, pitbulls both
times.

Why not just use the pepper spray? Bad dog owners/customers get
****ed off?

I have this little blue box that works pretty good on my two dogs when they
raise Cain from a visitor or a knock on the door. But its range is not that
good. It runs on a 9v. battery, and is a Big Lots item.

I would like to build one that is very strong, both for gaining some range,
and gaining the dog's attention.

The only reason they use ultrasonic sound is that people can't hear
it. It doesn't affect the dog any different than any other noise.
Could you use one of those canned air, air-horns?

Researching this, I find the 20,000 - 60,000 hz. range to be within their
hearing. Is there anywhere I can buy a simple tone generator, or kit that
will let me build one of these. Is tone generator what I need to be
searching for, or is there another term?

Long ago, I saw plans for something like that in 'Popular Electronics'
magazine.


--

Dan H.
northshore MA.