The CIR59 detects the presence of infrared (IR) beacons or sources.

The SENSITIVITY control sets the threshold at which the circuit functions.   There are many natural sources of IR energy such as the sun and incandescent and florescent lights.   The unit contains a Wratten™ optical filter to get rid of most of the annoying energy.  Adjust the SENSITIVITY control until the vibrator just stops.   Expose the CIR59 to the area under test or evaluation.  If the vibrator turns on and runs continuously, that means there is a continuous IR source.  If it pulses, that means an IR beacon is detected.

The unit contains two battery's; one 9 volt Alkaline for the detection circuitry and one AAA 1˝ volt Alkaline for the vibrator.   The LED on the front panel indicates the condition of the 9 volt battery.  If it goes out or flickers, replace the battery.   If the vibrator becomes sluggish, replace the 1˝ volt AAA battery.   Always use Alkaline battery's.

As with any piece of sophisticated electronic equipment, remove the battery's during storage.