I made eight QSOs on my first hour long straight key month shift operating as K3Y/6! Points of note: I'm still operating five watts from the kitchen window in San Francisco. The ' shiny F2 ' cutoff was not disproven. The critical frequency between San Francisco and Utah did go below 7,750 kHz and there was only one QSO that went east of Louisiana out to New York. That happened when the fof2 value was about 8200 kHz. Does the Data Fit with ND7K in Arizona? I noticed that while Utah had disappeared again, I was still being spotted in Arizona at 01:00 UTC. Looking at the fof2 values to the spotting station, ND7K revealed that this spot conformed to my evolving rule of thumb. The midpoint fof2 is at about 8,000 kHz at the time, so above 7,750 kHz. Note for future use: The rig's freuqncy/fof2 = 14.0574/7.750 = 1.8138 The factor is for use with this figure.