[time-nuts] Why are 1PPS signals so skinny?

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As most PSs for digital circuitry include a regulator, it's output 
impedance at 1Hz is low enough to "filter" most out of it - see the load 
transient response diagram of the used regulator - as the open loop gain 
of the regulator's internal error amplifier at such a low frequency is 
practically equal to that of DC gain.
While the 1Hz component is of no concern (power consumption left aside), 
the fast edges pose a higher demand on proper decoupling.

On 5/15/2012 9:45 PM, shalimr9 at gmail.com wrote:
> The narrow pulses are easily filtered by the power supply because the frequency distribution of the power consumption has a much smaller component at 1Hz.
>
> At 1Hz, the power supply filters nothing.
>
> Didier KO4BB
>
> Sent from my BlackBerry Wireless thingy while I do other things...
>
> -----Original Message-----
> From: Mike S<mikes at flatsurface.com>
> Sender: time-nuts-bounces at febo.com
> Date: Mon, 14 May 2012 20:44:04
> To:<time-nuts at febo.com>
> Reply-To: Discussion of precise time and frequency measurement
> 	<time-nuts at febo.com>
> Subject: Re: [time-nuts] Why are 1PPS signals so skinny?
>
> On 5/14/2012 8:21 PM, Tom Van Baak wrote:
>> one day during an experiment where I was
>> comparing a large set of clocks I noticed my lab's digital AC power
>> meter was jumping by tens of watts every second.
>>
>> The last thing you want
>> in a precision timing lab is to load your AC line down exactly once a
>> second.
>
> How does a short pulse help? It's still "tens of watts every second,"
> but instead of lasting 0.5 seconds, it lasts 0.00005 seconds. Less power
> used overall, but still the same sudden change on the second.
>
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