The K144XV module's specifications include an input noise figure of about 1 dB. This figure should be used when comparing the K144XV to external 2-meter transverters such as the Elecraft XV144 (which is about the same). This is the traditional way transverters are specified.
When the K144XV (or an external transverter) is connected to an HF transceiver used as a 10-meter IF, the composite receive noise figure is nearly always a little worse. This is because the HF transceiver's noise figure is typically lower than that of the transverter, and the transverter's own preamp has finite gain. (There's a "cascade" formula for determining the exact composite NF based on NF and gain of each stage -- left to the reader as an exercise :) For a typical combination of a low-noise transverter and its IF radio, the composite NF will be about 1 dB worse. That is the case for the K144XV+K3. We measure a noise figure of about 2 dB. If a transverter had a preamp with much higher gain, the effect of the IF receiver would be negligible. But the transverter would then be much more susceptible to IMD. 73, Wayne N6KR ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
