Small Mystery Siren

[tony991]

I just bought a small siren at a swap meet for $15. I apparently have to adjust the rotor out. It's missing the motor housing so there's no ID plate. It's stamped 1973 on the motor and just above the date it has a small shield with two diagonal lines stamped into it. The trumpet is 5.25" in diameter. Does anyone know what make/model this siren is? And if anyone has the motor housing I'll buy it from you.
Thanks!!

[sirendude2012]

That would be one of the most common small sirens ever, the Universal Security Instrument. Ademco also made sirens that looked like this.

What you have there is the complete package. The Relay and the Motor are supposed to be exposed. They were made for 60s burglar alarm systems. They are 12VDC, if you are hoping to run it.

In terms of sound output, expect something less loud than a Model A. $15 is a good price for these in good condition, but from your pictures it looks like you got what you payed for, pitting with rust and all.

Your relay looks like it might be bad, but I'm not a professional on relays so don't quote me on it.

[Daniel]

In the early 80's, sirens like this were sold at Radio Shack as car alarms.

[tony991]

Thanks for the replies and the info! It looked like it had holes for a motor housing but that's even better that it is in fact complete. The rust isn't really pitting. I'll wire wheel it and paint it and it'll look fine. I'll defiantly test the relay at some point.
Thanks again!