The man who knew everything

Pst! This is top secret. Don't let it get around, but we've got the Russians right where we want them. They haven't got a secret left to their name. We know every detail. You see, the Russians were pretty sure their inner circle was leakproof, that no one could penetrate their vaults. But they reckoned without—
By RANDALL GARRETT
He was sure of only one thing—he had a headache.
Dr. H. Wolstadt sat in a small, very secret laboratory in Arlington, Virginia, and twisted the dials on an oscilloscope. A pale green line wriggled up and down on the screen, and Dr. Wolstadt watched it with anticipation.
If this works, he muttered softly, more to himself than to his assistant, we will have a communication beam that will be better than radio.
The green line wriggled and changed form. Slowly, as the physicist manipulated the controls, the green line stopped moving.
There! shouted Wolstadt, that is the wave form we want! He reached over toward a switch. Check your meters, Magruder!
The assistant carefully adjusted the recording instruments of the huge machine that filled half the laboratory. All right, Dr. Wolstadt, we're ready.
Good! Wolstadt pressed the switch.
The assistant watched the meters and automatic graphs.
I'm afraid it didn't work, sir, he said at last. The instruments aren't reacting as you expected.
Wolstadt shrugged resignedly. Nevertheless, I think we are on the right track. Come, my boy, we will try again.