Massive MIMO (mMIMO) phase and amplitude controlled networks are the key RF technology of 5G. However, available phase shifters and attenuators that provide phase and amplitude control are narrowband, with typical bandwidths of only 200 MHz and have control resolution no more than 7 bits for sub-6 GHz and 6 bits for the mmWave bands. So building test systems to cover the 5G bands requires a significant investment in narrowband equipment, with performance insufficient to meet high test accuracy requirements. This article describes wideband designs for controlling phase and amplitude, offering the widest bandwidth--1.7 to 6 and 24 to 40 GHz--and highest resolution and accuracy commercially available. Two modules cover the 5G microwave and mmWave frequency bands with full 360 degree control and dynamic range to 50 dB and a resolution and accuracy of 0.1 dB and 1 degree sub 6 GHz and 0.2 dB and 2 degrees at mmWave. These phase and amplitude control modules serve as building blocks for beamforming, mMIMO, over-the-air (OTA) and multichannel signal simulator test systems. With their wideband coverage, resolution and accuracy, building test scenarios is simple and fast, reducing cost. [ABSTRACT FROM AUTHOR]