High Speed Measurements on Modulated Signals:This paper deals with the design and construction and measurement principles of a new high speed dual display channel power meter, the ML2480A series from Anritsu.Wideband modulated signals have historically been used in radar and microwave telecommunication systems. Developments in recent years have seen the application of high modulation rates to a number of new systems reaching commercial deployment, amongst these are Wideband CDMA and Wireless LAN.A key characteristic of these signals is a high degree of AM in the power envelope. Designers and manufacturers need to be able to measure and verify the peak and average power of the transmission power envelope. This paper outlines the design of a new power meter, which is able to accurately measure the real time variation in the power envelope.