Sunspot number.

Sunspot number. The 12-month running average of the number of sunspots for any month as indicated in the U.S. Department of Commerce Telecommunications Research and Engineering Report No. 13 - available from the Superintendent of Documents, Washington, DC 20402. The sunspot number varies in an approximate 11-year cycle.


47 CFR § 73.701

Scoping language

The following definitions apply to terminology employed in this subpart:

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