Latitude and Longitude: 
 Decimal Degrees eg: 43.50  -77.50
 D:M:S eg: 43:30:00 -77:30:00
 Use - for Western and Southern

MGRS Grid: 
 Nine Character Minimum, eg: 18TTN8878
Maidenhead Grid: 
 Four Character Minimum, eg: FN13
 Six Characters is typical 
US ZIP code: 
 Five Digits, eg: 14610
 At station location
US Telephone Area Code: 
 Three Digits, eg: 585
 for the station location 
 (not your own telephone number)

ZIP and Area Codes use the coordinates of the approximate middle of the area

Optional SSN (default=Current WWV Value):

Enter 0 for current Monthly Predicted Value
or any value greater than 1 for User Specified


Location: US State or 3 Character ISO country code 
Mode: Groundwave, GW/NVIS (may have multipath), NVIS, or Skywave
FOT: Optimum Frequency
MUF: Maximum Usable Frequency
TOA: Take-off Angle (use to select antenna type)

Solar Condition References: Other References:
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