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Electronics => RF, Microwave, Ham Radio => Topic started by: Circlotron on May 12, 2018, 11:26:11 am

Title: Accuracy of 774 ABC Melbourne frequency?
Post by: Circlotron on May 12, 2018, 11:26:11 am

Trying to zero beat the function generator by ear to the above station. Fades to a minimum every 1 minute 8 seconds with f/g set to 773,999.832 Hz. That set frequency is about 0.2ppm difference from the nominal 774KHz. How accurate might that particular station have it's carrier frequency set to?

Title: Re: Accuracy of 774 ABC Melbourne frequency?
Post by: dave_k on May 12, 2018, 11:48:41 am

Broadcasting Services (Technical Planning) Guidelines 2007, Appendix 1

"Unless otherwise specified, the frequency of the carrier shall be maintained within ±10 Hz."

Seems as though they are well within spec...

Title: Re: Accuracy of 774 ABC Melbourne frequency?
Post by: German_EE on May 13, 2018, 08:12:16 am

10 Hz, try harder, I can measure down to 0.1 millihertz at home.