Increased rate of rise of voltage on high power cathode pulsed crossed field devices

This paper discusses the maximum rate of rise of voltage (RRV) which can be applied to the cathode of a crossed field device. Recent developments in high peak power, narrow pulse width transmitters have indicated that the established criteria for RRV are not completely valid. Experience has shown that the RRV specified by crossed field tube designers is not a limitation inherent in the devices themselves but rather a function of the matching of the pulser to the tube. Attempts to achieve narrow pulse widths from magnetrons with conventional line type pulsers have tended to confirm the specified maximum RRV. However, when a Darlington or a Blumlein pulse forming network is used in place of the conventional network and pulse transformer, RRV´s two to three times higher than the maximum specified have been successfully applied with stable operation. The results indicate that RRV is relatively unimportant as long as overshoot of the modulator pulse is avoided.