5ed4b506_CB_vs__MCM_c_Comparison_Matrix__1
[0] Tuning passive elements to design specifications [2] Potentiometers and variable capacitors are used frequently to compensate for active device variability in applications where precise circuit performance is required [3] Filter response can be optimized by actively trimming critical components in the filter [1] 
Parasitic capacitive effects of tools and operators' hands degrade precision
Appendix A: A PCB vs. MCM-c Comparison Matrix
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