Hace meses escuché un test de audio de 55 segundos en 6185 Khz y me llega la confirmación y la explicación:
Thank you for your report and I confirm the details are correct. These transmissions were to fault-find on a 300 kW sender at the UK HF transmitter station at Woofferton.
The engineers needed a long test time as the fault was of an intermittent nature.
Babcock, Woofferton is the only remaining UK HF sender broadcast station and also is the only one with this transmission test audio and email address.
The audio is contained in a file playout system and incorporates non-copyright music and voice announcements from one of the employees at the transmitter site.
Thanks for your interest.
Dave G4OYX, (Retired) Senior Transmitter Engineer Woofferton 1982-2012.
Check out the video presentation of Woofferton on https://www.youtube.com/user/wooffertonuk
There is also the history of WOF on http://www.bbceng.info/Technical%20Reviews/technical_reviews.htm