Your homebrew Noise Source is only as good as the provided ENR value. Here we show how to achieve that. The drawback : you need a good Spectrum Analyzer. We used the FSP-3 from Rohde & Schwarz. This is our calibrated Reference.

Set the attenuator of the Spectrum Analyzer in manual mode to 0 dB. Connect your Noise Source and power it up. As this is a noisy thing, some averageing mayst be necessary. Set a marker on the frequency of interest and note the power. With the calculator below, you can then calculate the ENR value.

Starting with the (averaged) Power in dBm, we go to dBm/Hz by compensating for the RBW (resolution bandwidth). Adding the thermal noise of a resistor @ 300 K, we get the ENR value of the Noise Source.

If the amplitude response of your Noise Source is not that horizontal, several values mayst be a good idea to fully describe it.

The webmaster does not read these comments regularely. Urgent questions should be send via email. Ads or links to completely uncorrelated things will be removed.