[time-nuts] usb gps devices

[David]

The pulse per second output on the Garmin serial/CMOS interface units
is only specified to be within 1 microsecond.  I guess they are
commonly used to synchronize NTP servers where any extra precision
would be lost in network transport anyway.

I have been thinking of picking one up cheap to test since the
specification is so vague.  1 microsecond makes me think that the
pulse per second output is generated from a 1 MHz asynchronous clock.

On Wed, 26 Sep 2012 14:11:10 -0600 (MDT), "Don Latham"
<djl at montana.com> wrote:

>Have any of the 'nuts hacked one of the very simple very cheap GPS USB
>devices for your car top to see if there is an available 1 sec tick
>inside one of them somewhere? I have one that I intend to look at, but
>I'll have to get a scope and teenyweeny probe outside to do it, so, if
>there is a readily available something, I'd like to know. Thanks!
>Don