Two 90° mini-hybrid 3-dB couplers from Narda combine high isolation with compact size and the ability to meet military specifications for temperature, shock, and vibration. Model 4031C operates from 500 MHz to 1 GHz with isolation of at least 30 dB, insertion loss of less than 0.2 dB, and maximum voltage standing wave ratio (VSWR) of 1.25:1. The coupler maintains amplitude balance of ±0.6 dB and phase balance of 5°. Model 4034C operates from 4 GHz to 8 GHz, with isolation of at least 20 dB and insertion loss of less than 0.3 dB, and maintains amplitude balance of ±0.6 dB and phase balance of 10°. Both models have a maximum VSWR of 1.25:1, handle 50 W average and 5 kW peak RF input power, and have SMA female connectors.