WWV 5 MHz fom EM74vc

Festival of Frequency Measurement 1 October 2019

Jim Farmer, K4BSE  EM74vc

Started recording 20 Sept. 23:29:12, went well past the end of the day because I wasn't home to stop it earlier.  Decided to send all, so didn't cut it.

Antenna was a G5RV modified to favor WARC bands.  It gave a bit better performance than my 80M inverted VEE.  Receiver was K3 tuned to 4.999 MHz, USB.  It is stabilized by a GPS disciplined oscillator.  GPSDO had been running for months with no known interruptions.  RX had run for about 5 hours before the measurement period.  RX was set to a bandwidth of about 400 Hz centered on the 1 kHz beat.  The AGC seems to respond to what is in the total IF passband, not what comes through the crystal filter.  The receiver fed a SignalLink USB, feeding an HP laptop.  WWV calibration shortly before the start of the measurement period showed no significant frequency error.  HP laptop was running the current release of fldigi.

The large anomalies started around noon local time.  There was no discernable signal in the speaker then.

Enjoyed taking part.  Thanks; I had wondered what the WWV and Measurement modes in fldigi did - information is hard to come by.