Re: Strobing Message #6 Posted by Tom (UK) on 7 Oct 2003, 12:44 p.m., in response to message #5 by Ed Look
I don't know what rate the HP48G series updates the screen. Does a 'normal' house bulb give the same result as a street light (i.e. pulsing display)? If it doesn't visibly pulse then there is possibly some other effect.
From my recollection of electronics; if a light bulb runs from 60Hz the light will pulse at 120Hz. In the UK the mains electricity is 50Hz so lights pulse at 100Hz.
Light intensity = Power = ((Voltage)^2) / Resistance
If Voltage = V x COS(freq)
Power cx= (V x COS(freq))^2
Power cx= V^2 x 1/2(1 + COS(2 x freq))
(where cx= is 'proportional to')
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