众所周知,脉冲管子的栅极调制比阴极调制和阳极调制具有更多优越性,因此得到很大发展。但是通常的控制栅极要截获一部份阴极电流,比如15％左右。这使控制栅极发热,从而限制了它只能在小功率管范围应用。对大功率管来讲,就需要无截获的控制栅极。为了达到高放大系数和无截获的栅极控制,方法是紧挨着阴极的地方另加一个电极——阴影栅。 我国过去在行波管中,使用的控制栅极多是球面方格网孔钼栅极,这种栅极截获面 It is well known that the modulation of the gate of a pulse tube has more advantages than that of the cathode modulation and the anode modulation. Therefore, great progress has been made. However, the usual control gate to intercept a portion of the cathode current, such as about 15%. This heats up the control gate, limiting its use only to small power tubes. In terms of high-power tube, you need to intercept the control gate. In order to achieve high amplification factor and no interception of the gate control, close to the cathode plus an additional electrode - the shadow grid. China in the past in the traveling wave tube, the control grid used mostly spherical grid cell molybdenum grid, the grid intercepting surface