Ionosondes, or Chirpsondes, sweep from about 2000 kHz (2 MHz) to about 28000 kHz (28 MHz), depending on the exact station. It is not very often that I see one for more than about 6 to 10 MHz.

During the impact of the CME debris on August 3, 2010, from the C3 solar flare on August 1, conditions went very "wide". At the tiem I took this screen shot the SF was 81, A was 16, K was 5, and nT was 80.