Confused by Audio Frequencies

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dd0ul's picture
Last seen: 2 months 1 day ago
Joined: 2014/02/08 - 17:20
Confused by Audio Frequencies

I'm just experimenting with WSPR at 2m.The FT290RII (it seems that the drift is to high) is transmitting, I use a WebSDR ( in 5km distance to decode my own signal.

But I'm confused by the frequencies. The tranceiver is tuned to 144.489 MHz, wsjt-x (version 1.7.0, the release that can also operate wspr, running at a raspberry pi version 3) is configured to use 1500Hz as it's audio frequency.

On the receiver side I have to tune the WebSDR to 144488kHz (!) to get my audio signal with 1560Hz. But the wspr-x shows "Dial 144.489000" and "Tx 144.490500" while the spectrum scale start at 400Hz and stop at 600Hz.

All these frequencies does not match for me. The difference from 1500Hz is comprehensible, the labeling is confusing as well as the tuned frequency in the WebSDR.

Grateful for any explanation