engine noise

[billy182]

any ideas,started the other day its a noise like interferance through the radio a whizzing sort of noise when i rev the car it gets louder but now its noticable on tickover any ideas,the cars a phase1 172.

 

[AcID ZeR0]

s**t where do I remember this from, I can't actually remember but at a guess I'd say the problem lays with the Alt.
Come across this problem some way before can't remember the outcome or what exactly happened so it's annoying me now.

 

[billy182]

i was thinking alternator matey,but the aux belt goes round allsorts so bit baffled any one any other ideas,cheers.