|Frequencies||5748, 7250, 8188|
The traffic format is given below. The speed was 19 words per minute. Standard five dashes were used for zero.
|U||LOLO LOLO LOLO / 01723||LOLO / 01723||BT BT||89261 12616 ... 31657||AR SK|
|Tuning signal||5-figure message header||5-figure message header||Fixed-length message of 100 5-figure single groups|
|Repeated for 3 minutes||Repeated for 5 minutes||Repeated twice||Repeated twice|
Full transmissions always took roughly 26 minutes.
Prior to April 1998, M04 used the following schedule. The counting of the weeks started on the first Saturday of the month.
|Day||UTC||Freq||Week 1||Week 2||Week 3||Week 4||Week 5|
The U's at the beginning were initially repeated for 10 minutes. In April 1998, it was shortened to 3 minutes.
On 1 April 1998, the schedules above were replaced, and the following schedules came into use. The transmissions from now on only took place on the second Monday, Wednesday and Thursday, with the same message repeated throughout all the transmissions during the week. The counting of the weeks still started on the first Saturday of the month.
|Monday, Wednesday, Thursday|
The final M04 transmission was on 14 September 2000, however, blank carriers were transmitted for the length of E23 transmissions on its former schedules until 2002.
- Numbers & Oddities #32 (December 2000) [accessed September 13th, 2014]
- ENIGMA Newsletter #10 (January 1996), p. 7-8 - read a scanned version here
- Simon Mason, G2/E23 [accessed September 13th, 2014]
- Numbers & Oddities #8 (December 1998) [accessed September 13th, 2014]
Recording courtesy of Numbers & Oddities