Hal Murray wrote: >>>> So the cable delay should be a multiple of 317.375...ps. >>>> >>> What's the thermal coefficient of coax? >>> >> Typically around 50-100ppm/C depending on the coax. >> High velocity cables have lower tempcos >> > > Handwaving... > > 100 ft of cable is 70ns or 70000ps. > 100ppm is 7ps. > 10C is 70ps. > > So if you start out right, you will stay close but not right-on. > > I'm assuming the cable runs outside where the temperature isn't controlled. > > How much of your gear has a sticker on the front telling you how many ps > between the connector and the internal terminator? > > > Hal
This is why the antenna and cable temperatures are regulated in some geodetic GPS stations. Bruce _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
