Recovery Alarms!!!

[sandman]

Hey!!!

Look what I found at my local $1 store!!

OK they were $3.99 but you get 3 of them and the batteries are included!

These are window/door buglar alarms and they scream really lound like a personal alarm.

They are 1.1" wide but if you open them up (just one screw) and the PC board can be reduced easily to about 0.8" wide by cutting off the magnetic reed switch (that's the burglar alarm swith).

Neat!!

 

[Stones]

What's the weight w/o the outside case? (Batteries, circuit board, etc.)

 

[airwolfe1]

Darn it....that's where they came from. I just bought 1 alarm for 3 bucks plus shipping on e-bay.

 

[sandman]

What's the weight w/o the outside case?

Sorry, I don't have a scale. My guess is under 1 oz. Maybe way under.

The batteries are the heaviest thing and they are the little button cells (three of them).

The piezo buzzer is about an inch across but you may be able to substitute something smaller.

A really simple circuiut.

 

[wwattles]

A buddy of mine recently got a set of those, to use in his HPR models. His plan is to attach both of them to the shock cord, about 12 inches apart, and held together by a small piece of masking tape. When the shock cord is pulled out, the tape is broken, and the alarm goes off. Should be plenty loud enough to be heard from a looooong ways away.

If there's a way to vary the tone, we might want to look into it. Can you imagine being out on the range and 10 of these are going off at once while people are out looking for rockets in high brush/crops? Nobody would be able to find anything!

WW