And the air protection service, manufactured in the 1930s / 40s and still fully functional. As soon as the siren is operated by means of the crank, the air that is drawn in goes through. A rotating paddle wheel at the front.
Then the air is forced out through the openings on the. This creates a low hum / boom tone. When the crank is turned faster, the pitch of the.The volume can be adjusted with the lever on the top. Handy for you to know for the device, on top is a handle if you move it, you can open or.
Close the grille for a louder or softer sound, do not turn in the opposite direction and always. Allow the unit to turn off to avoid damage. The item "German WW2 Air Raid Siren HSM7 Hand Alarm Anti Aircraft Military Army (11.601)" is in sale since Sunday, March 28, 2021.This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\Other WWII Original Items". The seller is "buzzzmad" and is located in Heerhugowaard. This item can be shipped worldwide.