tight-beam n.

He’s putting it on a tight beam—that’s fine, we can chase it up.

‘Observation Officer of the Z12Q, attention!’ snapped from the tight-beam headquarters communicator. ‘Cut off those spy rays and report yourself under arrest for treason!’

This came on our own private, tight[-]beam, scrambled phone hook-up, just before the interference broke it up.

‘It’s not exactly code. All you need to do is record it and slow it down. They're not broadcasting at us. If a star has planets, inhabited planets, and there is broadcasting between them, they would send it on a tight beam to save power.’ He looked for comprehension. ‘You know, like a spotlight. Theoretically, a tight beam can go on forever without losing power. But aiming would be difficult from planet to planet. You can’t expect a beam to stay on target, over such distances, more than a few seconds at a time. So they'd naturally compress each message into a short half-second or one-second-length package and send it a few hundred times in one long blast to make sure it is picked up during the instant the beam swings across the target.’

I need to use your tight beam.

There was a snap of connection. No crackle of old-fashioned static this time. Sally had given me a tightbeam laser cluster.