The most common and most likely answer to this crossword clue is the 5 letter word MODEM
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More clues leading to the result MODEM
- Fashion initially marvellous computer device
- Lines bridging tiny distance forming connector
- Computer device rejected in some domiciles
- Network data device in its thirteenth configuration?
- Electronic device — type spymaster used
- Following fashion, Mike gets computer device
- Poem written in 2000 with outdated IT device
- It transmits miles over lines
- Shackled by flipping extreme dominatrix’s device
- Number of lines in program ultimately repeated in bit of IT kit
Buddy explains!

The straight part
We know that "data transmission device" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case data transmission device = modem.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MODEM mean?
MODEM noun- A device that encodes digital computer signals into analog/analogue telephone signals and vice versa and allows computers to communicate over a phone line.
- To transmit by modem.