IF Bandwidth setting / dBm accuracy in measurements
As a test, I have a known calibrated noise source of 68 MK @ 20 MHz. This gives me 9.4E-10 mW, and a calculated dBm of -90.3. I've tried every combination of settings but the closest measurement I can get my settings is -87.3 dBm. That is a pretty big difference between -90.3 dBm and -87.3 dBm (a 3 dB difference). Either my settings are incorrect, or the SA is not as accurate as I need it to be. I'm thinking that my IF bandwidth is not set correctly, or, I don't know for sure what number IS the IF bandwidth for my calculations.