Following the callsign, either the suffix -AM or -OC (Onda Corta, the Spanish term for shortwave) are included.
Sometimes, FM or television stations also have “XE” callsigns, but these are typically old (e.g., XETRA-FM and XETV-TDT).
The IFT issues call signs in the XE and XF series for amateur use, the latter mainly for offshore use.
[3] The call sign must be given always as enumerated on the permit, and the operator's location must be stated in Spanish.
Occasionally, other special call sign prefixes have been briefly allowed, such as XA5T, XB9Z, and XE0DX during amateur radio contests.