r8 - 2012-07-24 - 05:51:57 - DavidTaylorYou are here: NTP >  Support Web > InexpensiveOemGps
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ntp-4.2.8p4 was released on 21 October 2015, and addresses 13 low- and medium-severity security issues and provides about 100 bugfixes and enhancements over 4.2.8p3.

Please see the NTP Security Notice for vulnerability and mitigation details.

Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.

Inexpensive OEM GPS Receivers

With PPS

Garmin GPS-18LVC

Sure Electronics GPS Evaluation board

Without PPS

Globalsat BR-355, BU-353 and other modules using the SiRF chip sets.

These don't work very well. They have two problems.

  1. First is that they have a lot of jitter/wander. (The jitter is too low frequency to easily filter out.)
  2. Second is that they have a strange off-by-a-second bug if there is a leap second pending. This graph shows both quirks.
Topic attachments
I Attachment Action Size Date Who Comment
gifgif leap-gps2.gif manage 15.2 K 2008-11-21 - 05:19 HalMurray Plot of Leap Second glitch in SiRF chip sets
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