| русский | rus-000 |
| служебный канал | |
| English | eng-000 | engineering channel |
| English | eng-000 | engineering circuit |
| English | eng-000 | engineer’s circuit |
| English | eng-000 | information bearer channel |
| English | eng-000 | order wire |
| English | eng-000 | order wire circuit |
| English | eng-000 | orderwire |
| English | eng-000 | recording trunk |
| English | eng-000 | service channel |
| English | eng-000 | service circuit |
| English | eng-000 | speaker circuit |