You can get a poster of the radio spectrum for a very reasonable price (shipping included!) at https://bookstore.gpo.gov/products/united-states-frequency-alloca

You can get a poster of the radio spectrum for a very reasonable price (shipping included!) at https://bookstore.gpo.gov/products/united-states-frequency-allocations-radio-spectrum-poster https://bookstore.gpo.gov/products/united-states-frequency-a... (it's currently backordered).