I realize many people on the list are going to be familiar with the equipment and process, but it's interesting to see write-ups like this receive publicity on a larger scale. Especially when the article cautions "... get sucked into hacking frequency references and you may become a time nut <http://leapsecond.com/time-nuts.htm>" Hacking a Telecoms Frequency Standard for Your Lab <http://hackaday.com/2015/07/23/hacking-a-telecoms-frequency-standard-for-your-lab/> Nortel Trimble GPS DO Hack GPSTM <http://www.shaneburrell.com/?p=1071> -Neil