| 摘要 |
The loudspeaker is housed inside an outer casing, e.g. of a subscriber telephone set, which also contains printed circuits for transistors, capacitors, resistances, etc. The casing also houses a resonance box (1,2,3) for the loudspeaker comprising a sealed and vibration-damped compact unit. The resonance volume of the box is limited by a lower printed circuit (2) as base, and a similar circuit (1) at the top as cover. The box has an all-round frame (3) between the circuits (1,2) serving as side walls, and the loudspeaker (6) is fitted, vibration-damped, in one (1) of the circuits. There are also reinforcement components (12-14) between the circuits (1,2). These components comprise a stay (12) fitted centrally between the walls, and legs (13,14) counter-directed relatively to the stay, and locating against the upper and lower printed circuits (1,2). (Provisional Basic advised Week 84/17) |
