OMA (time signal) - Wikipedia

OMA was the callsign of a Czech time signal station. The station was operated by the Astronomical Institute of Prague and the transmitters were located at RKS Liblice 1.

The station transmitted in the LF band on 50 kHz with a power of 7 kW and in the HF band on 2500 kHz with 1 kW.^[1] A reserve LF transmitter was located at Poděbrady.

OMA, which could be also used for synchronizing radio controlled clocks, was shut down in 1995.

OMA time signal transmitter was used to synchronize radio clock. The transmit time protocol was changed multiple times. Periodic service maintenance outages lasted for days. The decoding was done in discrete hardware. Commercial use of OMA time signal was limited by absence of highly integrated receiver and decoding chip.

OMA was synchronized by Cesium Reference clock run by CSAV Czech Academy of Sciences, Kobylisy, Prague. Limited series of secondary 5MHz references with thermostat were manufactured by the institute. The secondary reference employed single transistor crystal oscillator with XF filter. The institute was under keen eye of communist party, dictating the R&D direction. They had there their devoted people. TV broadcasting and high reliability services were synchronized from the Cesium Reference. Today (2020) there are calls to resurrect the transmitter for resilience case. Performance of WWV beacon confirms the importance.

References

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^ Gerd Klawitter (1980). List of Time Signal Stations (9th ed.).

External links

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v t e Time signal stations
Longwave	BPC BPL BSF Beta DCF77 JJY RBU RTZ TDF time signal Time from NPL WWVB
Shortwave	BPM CHU HD2IOA HLA JN53DV ROA Time RWM WWV WWVH YVTO
VHF/FM/UHF	Radio Data System
Satellite	BeiDou DORIS GLONASS Galileo Global Positioning System IRNSS Quasi-Zenith Satellite System
Defunct	BSF HBG NAA OLB5 OMA Radio VNG WWVL Y3S

Time

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v t e Time measurement and standards
Chronometry Orders of magnitude Metrology
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50°04′22″N 14°52′47″E / 50.0728°N 14.8797°E / 50.0728; 14.8797