I cant figure out what this thing is. Its heavy, probably around 6 lbs. As you can see in the picture, inside the large hole is a semi hard membrane across it. Any ideas?
looks like an old brass Sireno Junior. Or perhaps an older hand crank version.
Shine a light down the smaller hole in the back and see if there are wires or if there is some sort of a cam that a crank handle would have hooked to.
Or just send the thread link to the Dig Gum Up; that fella would win the Who Wants to be a Millionaire of What Is It. dude must hold some sort of record in knowing what old odd looking things are.
I took it apart. Not much left inside after cleaning out the rust and corrosion, but enough to see that at one point it had electric running into it. Do the brass sirens have a membrane across them like this? If so, I'm guessing that this is an old electric siren.
Can you tell us exactly what it says on all the serial numbers? They might show up on a search. It does appear to be some kind of pressure regulator valve.
MICRO SWITCH
A DIVISION OF
MINNEAPOLIS HONEYWELL REGULATOR COMPANY
FREEPORT ILLINOIS USA
Just judging from the heavy bolts holding that thing together, it appears to be something that was subject to a lot of pressure - far beyond what any air horn would produce. Could be wrong, I'm certainly no expert on air horns.
Just judging from the heavy bolts holding that thing together, it appears to be something that was subject to a lot of pressure - far beyond what any air horn would produce. Could be wrong, I'm certainly no expert on air horns.
Looks a little like a MYAT 4-1/16" transmission line cover (as might be used with FM or TV broadcast transmitters).
You'll have to Google what one of those looks like on the MYAT web site. Part# 401-015