The envelope technique for trigger amplifiers

The author describes the envelope technique as a method for accommodating widely different magnetron RRV (rate-of-rise voltage) requirements for hard switch modulators. The configuration discussed has two trigger amplifiers whose outputs are summed on the grid of the switch tube(s) or on the magnetron to provide adjustable optimum drive voltage levels and time relationships. In the suggested configuration the first solid-state circuit drives the switch tube into conduction at the pulse voltage required to just bring the magnetron into oscillation. After a predetermined time required to build up an electron cloud needed for the proper mode of operation, a second pulse is applied which drives the magnetron into full peak operating conditions. The configuration provides full reproduction of incoming to output RF time fidelity with a nearly constant delay