Kok Chen wrote: > > So, I would like to suggest that Jim try using a stronger noise source > than band noise. >
Yes, think about this using common sense. Assuming typical band noise might typically be -120 to -130 dBm, and the internal noise floor of the radio is -137 dBm, you cannot expect to measure 60-70 dB down from such a low level noise source without running into internal noise floor problems. KS7D's swept measurement program does a much better job and requires only a signal source such as the XG1 or XG1. http://www.ks7d.com/Downloads.htm It also removes typical mistakes such as: 1. Not remembering to turn AGC Off. 2. Not remembering to lock the DSP filter much higher than the filter being measured so that there is no cascading effect. 3. Not adjusting Pitch to a frequency such that the low end is not truncated at 200 Hz by the MCU shifting the lower cutoff at low Pitch settings. 4. Not remembering the effect Mode (CW vs Data A) can have on measurements 73, Bill -- View this message in context: http://elecraft.365791.n2.nabble.com/250-Hz-and-400-Hz-Filter-Measurements-tp5300671p5308596.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
