This signals puzzling galore with Phi - source of happiness? (10)

I believe the answer is:

heliograph

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'this signals' is the definition.
The definition suggests a singular noun which matches the answer.

'puzzling galore with phi source of happiness?' is the wordplay.
'puzzling' indicates an anagram.
'with' means one lot of letters go next to another.
'source of' says to take the initial letters.
The first letter of 'happiness' is 'h'.
'galore' after 'phi' is 'phigalore'.
'phigalore' with letters rearranged gives 'heliograp'.
'heliograp'+'h'='HELIOGRAPH'

Can you help me to learn more?

(Another definition for heliograph that I've seen is " Device signalling by reflected sunlight".)

I've seen this clue in The Independent.

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