Finding Nearby & Previously-Used Frequencies

If you search for a frequency and get no exact match, a popup automatically offers two ways to widen the search:

Nearby Frequency Search

Choose a tolerance — ±5, ±10, ±15, ±20, or ±25 kHz — and the search expands to find anything close to the frequency you searched for. This is useful when you’re slightly unsure of the exact frequency, or a source has rounded it differently.

Previously-Used (Removed) Frequency Lookup

Alternatively, search the removed frequencies table — a historical record of frequencies that used to be assigned at that airport or unit but have since changed or been withdrawn. Results show the airport, service, frequency, channel, and the date it was removed, so you can see what something used to be even if it’s no longer current.