It knocked unconscious the two soldiers guarding the entrance to the shed the Army Engineers had built around the spaceship...
8 seconds sound clip from the The Day the Earth Stood Still (1954) classic radio play.
You can hear this line at 00:36:49 in the radio play.
Quote context
[...]
- At a conference table in Washington, a hasty council of the armed services was held.
- I wish I could be more specific, but all communications are out.
- In all likelihood to signal for this demonstration of his planet's power.
- Now, gentleman... Until now we've agreed on the desirability of capturing this 'man' alive.
[...]