What does radio timecode sync do?
Radio Timecode Sync generates browser audio that follows common long-wave radio time signal formats: JJY, BPC, DCF77, MSF, and WWVB. It is useful when a compatible radio-controlled clock cannot receive the real transmitter indoors, or when you want to test how a clock reacts to a known station format.
How to use it
Select the station that matches the clock, then place the clock's antenna area close to the device speaker or a wired headphone driver. Start with the built-in speaker; if the clock does not detect the signal, try over-ear headphones and rotate the clock to improve coupling. Keep the volume low and do not wear headphones while transmitting.
Accuracy and limitations
The generated time comes from this device's system clock plus the optional offset, so synchronize the device clock before using the tool. Browsers cannot emit the real long-wave carrier directly; this tool uses a lower-frequency square-wave approximation that may work through harmonics on some devices. Hardware, speaker or headphone driver placement, antenna alignment, and clock firmware all affect results, and JJY call sign audio is intentionally omitted.