Linking method: Connect the electric needle instrument of plus or minus pole respectively on the needle handle, and exchange poles every time.

连接方法：将电针仪的正负极分别接在针柄上，每次将正负极交换连接。

youdao

Note that two two-pole relays are used to connect each diode to the Model 2400.

注意，使用了两组双刀继电器将每个二极管连接到2400。

youdao

Experiment is performed and the result shows that the sharp electrode is the best and power supply should connect the negative pole.

荷电电极接电源不同极性时荷电效果亦不同，接电源负极所能够达到的最大荷质比较大。

youdao

The revised cabling setup allows 3.5mm cables to plug directly into the headsets, making for easier replacements and swapping (previous versions had you connect to a short cable hung from the earcup, with a dual-pole connector).

ENGADGET