EVLA Memo 156: Gain Distribution and Frequency Response of the T304 Input Stage
نویسنده
چکیده
This analysis seeks to identify whether (and to what extent) the variation in gain and frequency response observed in the T304 module affects the science results, and if so, how many and which circuit boards in the T304 require replacement in order to bring the variation within acceptable limits. The gain difference between the two types of circuit boards is being addressed by removing 7dB of excess attenuation from the lower-gain boards.
منابع مشابه
EVLA Memo #154 Characterization of the EVLA 1-2 GHz Intermediate Frequency Passband (Updated)
The EVLA 1-2 GHz Intermediate Frequency (IF), as presented to the 8-bit sampler, shows characteristic bandpass shapes that are independent of receiver band, upconverter path, or sideband. The implication is that the T304 baseband converter imprints its own characteristic response on the IF signal. This memo seeks to identify the causes of this characteristic shape, and to identify (where possib...
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تاریخ انتشار 2012