If it chirps, it’s armed.
The main portion of Targus’s Defcon 1 Ultra Notebook Computer Security System is a 3-foot covered steel cable that retracts into a plastic alarm housing, and uses a four-digit combination to lock the cable. When engaged, the alarm is sensitive to motion; it also sounds if the cable is cut.
There is a security lock adapter located on the other end that mates with a Kensington lock slot, and connecting it to your laptop is as easy as holding the adapter against the slot and pushing in on the end to attach it. The cable threads through the adapter, then back into the alarm housing, at which point an audible beep and flashing status light let you know whether the batteries still have juice. Finally, you just shuffle the combo lock’s numbers to secure your hardware.
Firm pressure on a button on the alarm housing activates the motion alarm at its low-sensitivity setting. Once active, the alarm chirps whenever it detects motion; even as you move the alarm after pressing the button. After a few seconds of chirping, if it still detects motion, it sounds the siren for about 45 seconds, or until the lock is unlocked.
We found the chirping noise a bit irritating, especially while trying to set the numeric wheels to unlock the cable. We also found it embarrassing when we triggered the alarm while trying to unlock the cable; we had more luck trying to enter the code as quickly as possible rather than trying not to move the housing.
The retractable cable is the thinnest of those reviewed for this feature; while this could make cutting the cable a tad easier, it also makes coiling the cable a cinch.
Prolonged motion activates the alarm. In many cases, however, the primary source of this motion will most likely be you, not a thief. Like other devices, it can be defeated, but not without causing a commotion.
Alarm is loud and unpleasant—exactly what we want would-be thieves to hear.
Chirping noise it makes when armed is irritating—and a bit embarrassing. Cable is on the short side. 
