Re: Newbie material on HF+

David Eckhardt

If you have an S-9 signal which is -73 dBm and you have set dBFS to 0 dBm, the dBFS should read -73 dBm.  If you have set full scale to -20 dBm, the dBFS should read -53 dBFS.  Likewise, if you set the dBFS to -73 dBFS, the dBFS should read 0 dBFS. 

Dave - WØLEV


On Thu, Apr 5, 2018 at 8:23 PM, Pete Smith <n4zr@...> wrote:

Please pardon the extreme newbie questions - I bought an Airspy HF+ recently, intending to use it on the IF of my K3 for spectrum display.  Of course, the K3 is off at Watsonville, so I've been experimenting, comparing the Airspy with a Red Pitaya and a QS1R.

From what I've seen I like SDR# a lot.  Is there anywhere an SDR# manual specifically for the HF+?  I keep running into things in the Quick Start that are not germane to my HF+, running the latest firmware.

Also, can anyone point me toward an explanation of the dBFS scale used for signal strength with the Airspy HF+?  I've established that my Elecraft XG-3's S-9 signal equates to 20 dBFS on SDR#, and its -33 dBM (equivalent to 40 over 9) more than "pins the meter" on SDR#.  Is this normal?  


73, Pete N4ZR
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Dave - WØLEV
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