- Date: September 27, 1921-March 1925... ( Note: According to published sources,[1]the station was converted from experimental amateur to commercial in 1923. However, this call appears in a March 1925 listing.)
- Frequency:
- 1053 khz (...March 1925...)
- Location:
- Monterrey, Nuevo León, Mexico (...March 1925...)
- Owner of license:
- Tarnava & Co. (...March 1925...)
- Subsequent call letters: CYO
The station was created in 1921 by Constantino de Tárnava Jr.[1]