Hey there.
If I remember my high school science textbook correctly, your dad was correct. Don't quote me on this, but I think it has something to do with the lower air temperature, at night, causing less distortion to electomagnetic waves than during the warm day.
So I would guess it should have an impact. Of course, the higher the frequency, the smaller the distortion.
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Ro:10:9 - If you confess with your mouth, "Jesus is Lord", and believe in your heart that God raised Him from the dead, you will be saved.