| 摘要 |
PURPOSE: To improve isolation so as to reduce crosstalk by using a multilayer board for wiring from an input/output connector, using a parts surface as a ground surface and pattern-wiring a signal line in an inner layer. CONSTITUTION: An audio signal from a TV transmission device 1 is applied to an input connector and connected to a signal input terminal 3 and a ground terminal 4. The terminal 3 is wired to the inner layer pattern 6 of a 4-layer board 2 via a through-hole 7 while the terminal 4 is wired to the pattern 5 of the parts surface and connected to a sound signal processing circuit. Thus, shielding is strengthened by inserting a signal line into the inner layer of the 4-layer board and when a number of signal lines are processed on the same board, isolation is improved and crosstalk is reduced. |
