The Phaser-Strobe pbx incorporates the unique design features of the Nova-Strobe dbx with an increased operating range of 30 to 50,000 flashes per minute, as well as external phase- shifting. The unique digital adjustment knob can select the decade for adjustments, so coarse and fine adjustments of flash rates are made quickly and with significantly better resolution than competitive units. The memory feature of the Phaser-Strobe pbx allows nine flash rates to be stored - displayed in flashes per minute or flashes per second. Phaser-Strobe pbx operates with internal rechargeable batteries or continuously from AC line power with the power supply/recharger.