[time-nuts] Re: Does cm accurate GPS via RTK give more accurate time?

[Ed Marciniak]

The LEA-M8F is the uBlox you’re referring to.

It features a 30.72 MHz VCXO that is steered to a clock bias of zero. The pulse per second is derived from a clock edge. (This is per their documentation).

It has been said that the phase noise of the 30.72 MHz source isn’t very impressive.

My gut says that phase locking a very high quality 10MHz ovenized oscillator with millihertz loop bandwidth is about as clean as you’ll get without spending thousands.

For what it’s worth, the M8F would be single band. There isn’t a 9 or 10 series frequency module.

The unicore timing module UT-982 doesn't specify how they get their 5ns one sigma specification for PPS.

For currently produced components or modules under 1500 USD, there is the LEA-M8F(single band), a couple part numbers from Furuno (all single band I think), and the Septentrio Mosiac-T for options that steer a clock rather than merely provide a PPS.