| 摘要 |
<p>A frequency analysing circuit e.g. for testing frequency convertors or quadripoles, uses a frequency generator such as a decade emitter to send a measuring voltage through the measured instrument to a selective heterodyne receiver and an analyser which can be tuned to a frequency different from the measuring frequency by a frequency source which produces the heterodyne frequency. The frequency generator is divided into two or more identical, mutually interpolating stages supplied with staggered reference frequencies. A switch divides the stages into two functional, non-interpolating groups, the second of which produces the measuring frequency or one of its components, whilst the first is used as the frequency source for the heterodyne frequency or one of its components.</p> |
