My engineering degree is over 20 yrs old and I haven't used those skills in 20 yrs.

I'm trying to make a "beacon" that will operate at around 3Khz using an integrated circuit.

I've been bopping around digikey and am getting confused with which components to choose.

Basically I need:

120vPS -> AC-DC converter -> tone Generator -> Amp -> Speaker.

I'm good with the converter, but the gen & amp combo is confusing me. The tone generator can be fixed frequency (by design) or variable, I don't care, but I do need to control the volume (probably 60db - 100db).

Any help is appreciated.

I think a simple 555 timer, maybe with a transistor to boost the speaker output, and the correct pot would work just fine. You’d have to scope the output or at least test it close as possible with a tone generator app for comparison.

(not shoe size thread. Backs out meekly)

isn't there an app for that? I'm serious. If all you need is a 3 kHz tone, I'm sure there's an audio generator app.

Failing that, get an R-Pi and just program it up using a USB speaker. Or a regular speaker, since the R-Pi has an analog speaker output jack.

I majored in it for one quarter back in 1983. I don't think I can help much though.

Just use a piezo siren- some have volume controls and can reach over 100db. Much simpler. I’ll see if I can find one that meets your specs.

quote:

Originally posted by radioman:
isn't there an app for that? I'm serious. If all you need is a 3 kHz tone, I'm sure there's an audio generator app.

Failing that, get an R-Pi and just program it up using a USB speaker. Or a regular speaker, since the R-Pi has an analog speaker output jack.

be cheaper & easier with an arduino
cheap 5Vac adapter, 3$ arduino nano, amp/speaker of your choice. wouldn't even need a breadboard, just solder direct.

tone library
Syntax
tone(pin, frequency)

tone(pin, frequency, duration)

this is what you need-
https://www.ebay.com/itm/105dB...b:g:w14AAOSwnHZYlV7G

^^^ Uh yeah, pretty much.

quote:

Originally posted by striker1:
I think a simple 555 timer, maybe with a transistor to boost the speaker output, and the correct pot would work just fine. You’d have to scope the output or at least test it close as possible with a tone generator app for comparison.

Not a bad way to go either. I hate pots though, and since freq doesn't need to be variable, find the divide ratio by tuning it in on the scope and then throw it away and put down resistors to divide the voltage down to the right level.

quote:

Originally posted by nshumway:
this is what you need-
https://www.ebay.com/itm/105dB...b:g:w14AAOSwnHZYlV7G

Thanks!

So I just need to put an AC-to-DC converter in front and I'm all set? (It has to work off AC)

Since its 6-16V, do I put a potentiometer in between to manage volume or db level?

Even easier than the pot for volume- I'd go with a 12 regulated power supply. Just connect it to the buzzer and you are done. The siren in the link has a volume control- you rotate the top and the opening becomes bigger or smaller, allowing more oe less sound out.