21st century problem

[Richard]

What!? No points for trying? :(

[F Murtz]

Don't usually pick on misspelling but you have two fluorescents both wrong

[Harry Bloomfield]

I can be relied upon to ALWAYS misspell it when I'm in a rush. lol

[Jeremy Nicoll - news posts]

Is this a terminology problem? Mains is generated at around 50 Hz, but that means 50 /cycles/ per second; each full sinusoidal cycle crosses 0 twice in that time, so in 50 Hz we'd have 100 no-volt conditions, and hence the strobe would happen 100 times per second.

[Dave Preston]

Rod Speed brought next idea :

I've still got all my original Led Zeppelin, Rolling Stones, Deep Purple, Emerson Lake and Palmer, King Crimson, Yes, The Moody blues etc., etc., etc vynil from my teenage days in the seventies and still play them. Nowt wrong wi vinyl - much better than intangible mp3 downloads or even CDs. And you got proper cover art as well!

[Bob Eager]

Copy it to a CD.

[Richard]

A pox on you, sir! I had to abandon mine many years ago :(

[Andrew Gabriel]

You reminded me of something I long since forgot about from my childhood; a couple of metal disks marked with strobe lines to sit on the turntable. One was same size as a 7" record and had lots of speed gratings on it - 33,

45, 78, and a couple of others IIRC. The other only had 33, and was designed to sit in the middle of an LP on top of the label.

Not seen them for decades, so I suspect long since lost.

[Richard Tobin]

Google "printable turntable strobe" (without the quotes).

-- Richard

[dennis]

They hardly ever flickered at 50Hz. A true audiophile would turn in his grave at the thought of using mains as a reference frequency.

[Richard Tobin]

They're all dead then?

-- Richard

[meow2222]

They're all dead, all male, and all agree with Dennis.

NT

[polygonum]

And if they are not dead, they buy this:

[Mr Pounder]

Brian:

I understand that Rod Speed is Australian. Australians are quite a stupid breed. However, I have never seen him post this way before. Perhaps it is not him?

[John Rumm]

Yup, its what mine has...

[John Rumm]

A LED, 1N4007 (or any similar rectifier style) diode and a 100K 1W resistor can be wired across the mains and will strobe at 50Hz

[Johny B Good]

ITYM "100Hz Flicker".

[Johny B Good]

GIYF :-)

[Johny B Good]

Use a small desklamp with a tungsten filament lamp fitted. A tungsten filament lamp will still flicker at 100Hz (assuming 50Hz nominal mains frequency).

If your turnatable has an actual speed adjustment feature built in, it's a little unusual that it doesn't also include a built in 100Hz strobe lamp (usually neon).

Whilst the mains provides an accurate long term reference such that old fashioned electric wall clocks can remain within a minute of true time day by day 7 days a week for all 52 weeks of the year, year in year out (assuming no outages), it's not a very stable reference in the short term (minute by minute) so you need to resist the urge to chase these short term changes of 'apparent' turntable speed' (assuming the turntable speed stability is any good in the first place).

[Johny B Good]

The variation is normally kept within +/- a tenth of a Hertz (+/-

0.2%) but can vary up to half a Hertz (+/- 1%). Any greater than that and you're just as likely to end up in the dark (turntable speed accuracy becomes a rather academic consideration when it stops spinning for lack of mains power unless you're running of a power outlet protected by a UPS).