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A comment on What Happened in the UK Blackouts?. Parent comment

Re:What Happened in the UK Blackouts? by circular_logic on Sunday September 01, 2019 @07:25AM (#20851691)
That makes me wonder, if you were standing next to these turbines would you be able to here them slow down?
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Re:What Happened in the UK Blackouts? by fanf2 on Sunday September 01, 2019 @07:48AM (#20851775)
The change in pitch from 50Hz to 48.8Hz was 0.4 semitones.

12 * ln 50 / ln 2 = 67.7

12 * ln 48.8 / ln 2 = 67.3

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Re:What Happened in the UK Blackouts? by kalleboo on Monday September 02, 2019 @11:56AM (#20859855)
This is kinda unrelated (it involved a line frequency slowdown from 60 Hz to 51 Hz), but I always found this radio recording of the US northeast blackout of 1965[0] fascinating as the DJ is grappling with records/tape cartridges slowing down and lights dimming live on the air https://www.musicradio77.com/images/ing11-9-65blackout.mp3

[0] https://en.wikipedia.org/wiki/Northeast_blackout_of_1965#Rad...

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Re:What Happened in the UK Blackouts? by mnx on Sunday September 01, 2019 @01:06PM (#20853317)
If I listen carefully, I can tell the difference between 48 and 50hz using a sine generator (although it's very subtle), so I'd guess that you possibly could.
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Re:What Happened in the UK Blackouts? by bsder on Sunday September 01, 2019 @04:47PM (#20854791)
Probably, although you are more likely to hear the 3000Hz to 2880Hz change in the generator RPM than the 50 to 48.8 change in the output.
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Re:What Happened in the UK Blackouts? by Iwan-Zotow on Sunday September 01, 2019 @10:49AM (#20852562)
Yes
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