#400: Measuring the Minimum Discernable Signal and bandwidth of the 40m Direct Conversion receiver. @w2aew

Uploaded June 2025 | Updated September 2026, 2 weeks ago

This video shows the measurement of the Minimum Discernable Signal level (MDS) of the Soldersmoke Challenge Direct Conversion 40m receiver - which is a decent measurement of the sensitivity. I also show the measurement of the receiver bandwidth, and then use that to "correct" the MDS value so that it can be basically compared to the standard measurement of MDS which uses a 500Hz receiver BW. More information on the receiver I'm testing, see video #398 and the notes shown for that video:
youtube.com/watch?v=XmUsA62CSuA

#400: Measuring the Minimum Discernable Signal and bandwidth of the 40m Direct Conversion receiver.

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