This was later identified by a fellow mainland Chinese hobbyist as a test signal from the Jiangsu People's Radio division of the provincial government-owned Jiangsu Broadcasting Corporation, but was later accidentally turned into a temporary infinite loop of personal care adverts, due to STL configuration mistakes at their transmitter in rural Nanjing.An unidentified sine wave located around 1542 kHz has been present in random recent nights.
I have also checked with other fellow DXers in mainland China, and the wave was reportedly audible across most of the country, ranging from Guangdong/Canton to Liaoning (northeast, part of so-called "Manchuria") south to north.
Wild guess: technical mistake by NRTA Station 623*, Changzhou/Changchow, Jiangsu/Kiangsu Province.
QTH - Urban central Beijing; Equipment - Tecsun PL-310ET
*Transmitting site of the only CNR1 on 1593 plus CRI Japanese on 1044
Local authorities admitted that using such contents as test signals are indeed improper, and JSBC was reportedly been notified by authorities to change the testing content consist.
Edit: grammar mistakes
