Nothing current in old transmission (7)

I believe the answer is:

podcast

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'transmission' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'nothing current in old' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'current' becomes 'dc' (abbreviation for direct current).
'in' indicates putting letters inside.
'old' becomes 'past' (similar in meaning).
'o'+'dc'='odc'
'odc' placed inside 'past' is 'PODCAST'.

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(Other definitions for podcast that I've seen before include "Audio file distributed over the internet" , "Downloadable sound file" , "Downloadable programme" , "digital recording" , "Web feed" .)

I've seen this clue in The Times.

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