The Siren Board

The same siren as before, I've just added a protective screen and hooked up my 555 wail timer.



Since this vid I've tweaked the timer so that it cuts back on quicker during the wail. The timer assembly is shown at the end

http://www.youtube.com/watch?v=Yto68JCk4g4

Turn your speakers up for this one and listen for the echo, it's very faint. That's what you get for filming with a cell phone.

http://www.youtube.com/watch?v=K4-PMwRx8k0

Hopefully I will get a decent recording device that really captures the sound of this siren.
Any questions just ask.

The siren looks homemade. Is it? (You only state that the timer's homemade.) Reminds me of those mechanical car alarms, with the quick wind-down and fast wind up.

I like the timer... as "homemade" as it apparently is. Ever considered getting a shoebox? Seems like that's very vulnerable to flying water from the sky if taken out of that garage-like protective building! (Sorry, going crazy tonight for some reason.)

The siren is a $13.50 ebay unit that has been "slightly" modified (here is what it used to look like http://www.airraidsirens.com/forums/vie ... 03&start=0)

The timer is still in the experimental phase (that is why it's still on a breadboard). The whole thing is based around the 555 timer. I have the wail timer nailed down and I also have one for a one minute alert tone. You simply press the button, it sounds for one minute in whichever mode you choose and shuts off automatically.

Once I get it working like I want it will be transferred to a circuit board and mounted inside the gray(soon to be yellow) weatherproof box that can be seen under the bee flag in the photo.

I hooked up three 100,000uf caps to the siren today and the winddown is SO much better.

Here's a vid

http://www.youtube.com/watch?v=wSaOekaEko0

Sounds nice. Have a name for the siren?

Looks like a baby Erick or Decot.

how exactly did you hook up the caps? i bought that same siren.

thunderbolt69 wrote:Sounds nice. Have a name for the siren?

I haven't really thought about naming it yet, have any ideas?

cyclonesthebest wrote:how exactly did you hook up the caps? i bought that same siren.

Look at this picture closely, shows all the caps hooked up and will explain most of the concept.



Line up your caps with all the terminals like this

- - - -
+ + + +

Tie all the caps together with jumpers (do NOT wire them up backwards, electrolytic, capacitors WILL explode if wired incorrectly) and basically hook the caps up inline with the siren and power source. Run the positive wire from the power supply to the positive terminal on the capacitor, and then hook the positive wire from the siren to the positive terminal on the capacitor. Hook the negative wire from the power supply to the negative terminal on the capacitor, and then hook the negative wire from the siren to the negative terminal on the capacitor.

haha Looks like a mini Decot siren. Nice job on the casing.