Jim Lux wrote:
The soundcard program I used, Argo, permits a frequency calibration coefficient to be entered. I used the 1800 Hz third harmonic of the WWV/WWVH 600 Hz tone as demodulated by the TS-870S in its AM mode as a calibration standard. When ionospheric fades null the carrier, the demodulator distortion peaks and makes the audio third harmonic visible in the Argo spectrogram.
Argo is a really excellent tool; one of the guys who does the "multi-multi" FMT with me uses it and it has some very cool features for this application. And cool idea about using the distortion to get a calibration source!
John
