A free CD-ROM from Keithley Instruments, "Making Quality RF Measurements That Save Time, Money, and Effort," is a useful resource for any engineer or technician involved with making RF device or component measurements. The CD contains a library of application notes, white papers, and even a link to an on-line seminar to help improve the quality of RF measurements. Copies of the disk are free, but require a log-in procedure. For more information, visit the Keithley website at: http://www.keithley.com/