Why Hai Yung's long-range radio was unreliable

What was wrong with the quality of Hai Yung's long-range radio?

As recalled, the radio combined poor construction and limited power with poor maintenance of the particular set aboard ship.

Hai Yung's long-range radio is remembered as a poorly built system. It also lacked power. The particular unit aboard ship is recalled as poorly maintained. Both the equipment's construction and the condition of the installed set therefore contribute to this qualified explanation of its shortcomings.