The coverage area for the GOES time service was larger than other time code services in the pre-GPS era (Fig.
Once the time code service had begun, it was obvious that GOES time code receivers must be made available before the new service would acquire any customers.
Complete plans for a GOES time code receiver, including schematics and assembly language source code, were published in NBS Technical Note 681  and widely distributed.
It was noted in 1978 that NBS had been contacted by "more than 18 manufacturers" who were interested in building GOES time code receivers and by then, several commercial models were already available .
Time and Frequency Control and Uncertainty of the GOES Time Code Service
Other incidents that increased the timing uncertainty were satellite maneuvers, where NOAA sometimes moved the satellites to a new position before new orbital elements were available and the position data in the TCGs could be updated; and solar eclipse periods, when the time code was sometimes moved to a spare satellite for periods as long as two hours each day .
Orbit prediction software was always an essential element of the GOES time code service.
GOES time code receivers were once widely found and heavily relied upon at airports, electric power companies, scientific laboratories, observatories, and military installations.
The largest users of the time code were probably the Federal Aviation Administration (FAA) and the electric power industry in both the United States and Canada.
Perhaps more importantly, the experience gained by developing GOES time code receivers [35-37] no doubt played a role in the development of the first GPS common-view timing receiver in 1981 , which is still used today by NIST and other national laboratories for international time comparisons.
After its initial development, the GOES time code service was efficiently operated, with minimal cost to NBS/NIST.
NBS and NOAA signed three MOAs to provide the time code service.