[time-nuts] Why a 10MHz sinewave output?
paulswedb at gmail.com
Mon Feb 6 14:14:36 UTC 2012
Indeed the long cable runs are tough. Though today we have differential
cable drivers that do quite well to the Ghz range. But certainly back in
the dark ages the sine wave was a very reasonable way to go.
On Mon, Feb 6, 2012 at 3:56 AM, Attila Kinali <attila at kinali.ch> wrote:
> On Sun, 05 Feb 2012 19:50:28 -0800
> bob grant <bobgrant at fastmail.fm> wrote:
> > Why is 10MHz output of many sources or distribution amps in the form of
> > a sinewave?
> > Is it something to do with signal reflections or ease of isolation?
> > Since zero crossing detectors are susceptible to noise wouldn't a fast
> > TTL square
> > wave be more appropriate for signal distribution within a equipment
> > rack?
> The advantage of a sine wave is that you have a single, bounded frequency.
> A square wave has quite strong components at odd multiples of the base
> frequency, theoretically going up to infinity. To get a "good" shape
> of the signal you need at least the first three of the harmonics, resulting
> in a seven times increased bandwidth need.
> Beside of the more complicated handling of the higher frequency components,
> you also have to think about dispersion of the signal if you go trough
> filters or use longer cables.
> Attila Kinali
> The trouble with you, Shev, is you don't say anything until you've saved
> up a whole truckload of damned heavy brick arguments and then you dump
> them all out and never look at the bleeding body mangled beneath the heap
> -- Tirin, The Dispossessed, U. Le Guin
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to
> and follow the instructions there.
More information about the time-nuts