The time code generator GEN170 has been designed to generate all signals required to control or simulate a DCF77 compatible long wave transmitter or provide the reference time for an NTP server:
- 77.5 kHz carrier frequency
- Second marks to modulate the carrier’s amplitude
- PRN sequence and PRN window to modulate the carrier’s phase
- Pulse-per-Second (PPS) output
Additionally, an IRIG or AFNOR time code signal is generated, and a serial time string can be transmitted which includes the generated absolute date and time.
Internal date and time is always based on UTC (Universal Time, Coordinated; formerly GMT, Greenwich Mean Time). A configurable time offset can be applied to the UTC time base to compute a local standard time. Beginning and end of a period of daylight saving time can either be computed year by year based on a simple, configurable algorithm, or can be configured for the current year. GEN170 generates the proper changeover announcement flags as required by the DCF77 coding scheme.
Additionally, a date for insertion of a leap second can be configured. GEN170 automatically generates the coding sequences to announce the leap second as required for DCF77 and NTP, and also inserts the leap second correctly.