[time-nuts] Why are PPS pulses so narrow? (was: 53132A triggering)

David davidwhess at gmail.com
Sat Sep 17 15:35:21 EDT 2016

I would not use such a narrow pulse for any of those reasons except
for power if that was an issue.  I would and have however used narrow
pulses simply because it allows for a lower volt*time product on a

On Fri, 16 Sep 2016 21:03:12 -0400, you wrote:

>It is sort of an " everybody does it " sort of thing. Various justifications:
>        Less power is used / less heat in the drivers and terminations.
>        Transformer coupling works better ( lower delay ) with narrow pulses
>         Anything over 1 us has been "really long" in terms of logic speeds since the 1960's
>         A definite duty cycle "bias" let's you detect an inverted pulse.
>The only real reason is "that's the way it's done". Big Customers ask for it that way. Suppliers deliver what is asked for. Nobody complains, nothing changes.
>> On Sep 16, 2016, at 7:44 PM, Peter Vince <petervince1952 at gmail.com> wrote:
>> Can I ask why PPS pulses are so narrow?  It makes them difficult to see on
>> a 'scope, and difficult to detect on a PC.  And, as Bob said, far less
>> obvious if you trigger off the wrong edge.
>>     Peter

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