95GHZ SPECTROMETER PULSED EXTENDED-INTERACTION KLYSTRON

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 随着我们最近完成对集成的95 GHz频谱仪扩展相互作用速调管(EIK)脉冲调制器的升级(在子项目0252中详细说明)，Acert进入了显著改进高功率脉冲HF ESR波谱的新时代。初始高功率射频。在整个光谱仪中的测试表明，现在可以调整EIK管偏置和选通光束的“开启”时间，以达到基本上不可测量的功率下降，间隔最高可达800 ns。然而，从我们最初的升级后经验调整和观察中可以明显看出，我们在高功率脉冲下的EIK偏置要求与制造商(CPI，Inc.，加拿大)的规格有所不同。因此，我们启动了一个适度的计划，以获得在不同偏置和驱动条件下更完整的管子性能图景。 在最近的升级计划之前，我们已经发现EIK在(当时固定的)1？S光束“开”时间内表现出显著的功率下降。在饱和模式下，测得的下垂为初始输出功率的21%的容许值，但非饱和下垂的测量表明，在束流脉冲间隔内有极高的78%的功率损失。在加入调制器升级和修复由于元件故障导致的调制器焦点电极偏置电源偏置之后，观察到大致相同的下垂值。然而，随着H.V的调整，EIK功率下降特性显著降低。开关电源高于之前的3KV限制。这一观察表明，最佳R.F.所需的聚焦电极电势。射束“开启”时间内的功率提取可能比CPI提供的0？20V规格更积极。我们将在短期内研究最好的即时偏置调整，以同时最大限度地减少功率下降和调制器昂贵的高压过电压风险。换个位置。这些研究将在正常范围的运行参数条件下进行。从长远来看，我们将拆除调制器盒，目的是确定对调制器进行必要的修改，以完全消除下垂效应。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. With completion of our recent upgrades to the integrated 95 GHz spectrometer extended-interaction klystron (EIK) pulse modulator, detailed in Subproject 0252, ACERT has entered a new era of significantly improved high-power pulse HF ESR spectroscopy. Initial high-power r.f. tests in the complete spectrometer indicate that the EIK tube bias and gated beam "on" time can now be adjusted for essentially unmeasurable power droop for intervals up to approximately 800ns. It has become evident from our initial post-upgrade empirical adjustments and observations, however, that our EIK biasing requirements under high-power pulsing are somewhat different than the manufacturer's (CPI, Inc., Canada) specifications indicate. Therefore, we have initiated a modest program for achieving a more complete picture of tube performance under different bias and drive conditions. Prior to the recent upgrade program, we had found that the EIK exhibited significant power droop during a (at that time fixed) 1¿s beam "on" time. In saturated mode the droop was measured to be a tolerable value of 21% of initial output power but the telling measurement of unsaturated droop indicated an extremely high value of 78% power loss over the beam pulse interval. Following incorporation of the modulator upgrades and repair of a modulator focus electrode bias supply offset due to component failure, approximately the same droop values were observed. However, a dramatic reduction of the EIK power droop characteristic was observed with adjustment of the h.v. switch supply above the previous 3KV limit. This observation indicates that the required focus electrode potential for optimum r.f. power extraction during the beam "on" time may be more positive than the 0¿20V specification supplied by CPI. We will in the near term investigate the best immediate bias adjustment for simultaneously minimizing power droop and overvoltage risk the modulator's expensive h.v. switch. These studies will be performed over the normal range of operating parametric conditions. In the long-term we will remove the modulator box with the goal of determining necessary modifications to the modulator to eliminate the droop effect entirely.