Federal Signal SD-10, Growl, Palo Alto, California. 

i didn't have my tripod with me so i held it as steady as i could

I figured it would still work. All of Palo Alto’s sirens are fresh looking.

First! 30 seconds ago! Nice video ! I love sd-10s they sound like ACAs a lot because the port ratio

Not a surprise that it still works. Electro-mechanical sirens ftw!

That's awesome! SD-10s are pretty cool man.

Wow, I thought these "Cold War Era" Sirens in California did not work anymore! Here in Illinois we have lots of active SD-10's

Good video. Glad to know it works.

Wasn’t this the same place that had that supposed hedberg siren? Like the horizontal single head thingy

0:19 is this Like a Old Cold War era siren

These things were built to last. its probably its first activation in like 2 decades.

I didn't think they would do a growl test when asked.

Firefighter that activated it said it hadn't been used in over 20 yrs!

WTF