With the help of Wei Chaopeng, a member of Qing-Hong Brotherhood, Tu Zuochao and Li Xiangwu were back in Shanghai. After that, through a secret channel, Tu Zuochao arrived at the Red Army Headquarters located at Qingtang, Ruijin County, Jiangxi Province on March 20, 1931.

During his time in Jiangxi Base Area, besides his job as the radio engineer building and maintaining the radio stations, he was also responsible for the radio training class there. It was because of this, he became acquainted with Li Bai, the original figure of the hero Li Xia in the movie The Eternal Wave. They therefore had had a friendship between the master and the apprentice ever since. In Autumn, 1935 when the 5^th Anti-annihilation campaign failed, the Red Army had to begin its Long March. However, Tu Zuochao was not included in the Long Marchers. He was left in the Soviet Base Area for the guerrilla war. In February, 1935, Tu Zuochao was assigned to work in West Hunan Province. The KMT blockade kept him from reaching his destination. By this time, his way back to Jiangxi Base Area was blockaded. In his desperation, Tu Zuchao wandered eastwards to Shanghai. After one year’s endeavor, he eventually found the CCP underground connections. By this time, the Red Army had arrived in North Shaanxi Province.

In Autumn, 1936, Tu Zuochao suddenly received a CCP secret order asking him to rush to Xi’an.

Zhang Yi: Before the Xi’an Incident, you father had been in Xi’an already, really?

Shenghua: Yes. CCP did not have their own transceiver in Xi’an. Had to use the radio facility of Lt General Wang Yizhe, an army commander of the Northeastern Army. But CCP needed their own radio and so CCP sent Tu Zuochao to Xi’an. He made the first CCP transceiver in Xi’an. It was a 5-Watt one. He spent about a dozen dollars and bought a second-hand Japan-made radio set. He modified this radio set and made it a transceiver with an output power of 5 Watts. Right after the first radio station he had made the second one. The output power of this second radio station remained 5 Watts but this radio station could use either AC or DC. This AC-DC radio station played its role on the day when the Xi’an Incident took place. On December 12, 1936 when the Double 12 Incident took place, electricity supply in Xi’an stopped. The news that Jiang Jieshi was arrested was sent by the DC section of this AC-DC transceiver.