[ntp:questions] site with lots of GPS's and accessories

Chris Albertson albertson.chris at gmail.com
Mon Mar 19 18:01:10 UTC 2012

On Mon, Mar 19, 2012 at 10:25 AM, Alby VA <albyva at empire.org> wrote:

> On Mar 19, 12:12 pm, unruh <un... at invalid.ca> wrote:
> > The actual PPS signal at the PPS pin has a rise time of about 10ns, and
> > the Sure has a normal sawtooth timing signal, so that would indicate a
> > few 10s of ns accuracy from the Sure, but the conversion to RS232 washes
> > that out

Does the conversion to rs232 add uncertainty or simply a fixed delay.   I
can't believe the conversion is so noisy.  it can be done with a single
2n2222 transistor or if you care about speed find a faster RF transistor
that works at UHF.

I guess I could measure a or simulate a level converter but my guess is
that it adds only a few nano seconds of noise.   Fixed delays don't matter

Chris Albertson
Redondo Beach, California

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