I ignored him and turned my attention to Army business. The meteorological equipment was functioning perfectly, but our orders read that one of us had to check it every twelve hours. So I checked and tried to keep my eyes from wandering as Rizzo tinkered with a photocell and oscilloscope.
"There we are," he said, at length. "Now let's see what they're telling us."
In spite of myself I looked up at the face of the oscilloscope. A steady, gradually sloping greenish line was traced across the screen.
"No message," I said.
Rizzo shrugged elaborately.
"If you leave the 'scope on for two days, you'll find that the line makes a full swing from peak to null," I informed him. "The star pulsates every two days, bright to dim."
"Let's turn up the gain," he said, and he flicked a few knobs on the front of the 'scope.
The line didn't change at all.
"What's the sweep speed?" I asked.