Transient1
Mechanical
A previous engineer put forth an FEA analysis of an electrical chassis. For simplicity, imagine that it is a box with a cover and two levels. There are two circuit boards mounted to the base with standoffs. On the second level there is one board mounted with standoffs directly to the mid-plate. Also, on the second plate is a stack up consiting of circuit board/Rectangular metal RF shield/Circuit board. Each of those components are connected by standoffs.
Assume that the natural frequency of the chassis is 2600 Hz, and that the boards have various frequencies within 200 Hz of each other. The chassis experiences random vibration in the 20-2000Hz range.
An issue has been raised that those boards with frequencies near each other will couple dynamically through the chassis. This just does not seem right. The mass of the PCBs are much less than the chassis. Is it correct that the chassis mounted boards will not couple but the stack up can couple? Any advice and resources are welcomed.
Assume that the natural frequency of the chassis is 2600 Hz, and that the boards have various frequencies within 200 Hz of each other. The chassis experiences random vibration in the 20-2000Hz range.
An issue has been raised that those boards with frequencies near each other will couple dynamically through the chassis. This just does not seem right. The mass of the PCBs are much less than the chassis. Is it correct that the chassis mounted boards will not couple but the stack up can couple? Any advice and resources are welcomed.
