Cercis Inc.'s 610 series data-logging optical power meters can store up to 1000 records, each including a user-assigned alphanumeric label, power readings, reference value, calibration wavelength, operating mode, date and time. Via an RS-232 port, the records are downloadable to a PC with the aid of Cercis Testworx software. The four models encompass power inputs from 5 to -75 dBm and wavelengths from 350 to 1800 nm. Housed in thermoplastic cases, the 3 x 5 x 1-in. devices can operate for more than 50 h with one 9-V battery.