Manufacturing Notes
Mandatory mechanical verification before fabrication
The current PCB outline and all existing component and connector placement are to be preserved. However, the present five nominal 3.2 mm circular NPTH mounting holes and the board slot geometry have not been verified as exact matches to the original JBL Charge 3 I/O board.
Before releasing fabrication files, verify against an original JBL I/O board using direct measurements or a trusted mechanical drawing:
- Mounting-hole count, shape, diameter, and plated/non-plated status
- Hole-center coordinates and edge offsets
- Whether any circular holes must instead be elongated slots
- Slot width, length, corner radius, orientation, and center coordinates
- Clearance/keepout boundaries associated with the enclosure and mounting features
Fabrication status: Mechanical mounting-hole and slot geometry is provisional and requires verification before ordering PCBs.
Applied photo-derived mounting correction
The five temporary identical 3.2 mm circular NPTH holes were removed. Three round mounting features supported by the JBL drawing and PCB photograph were added using the user-approved provisional 2.75 mm NPTH diameter:
- Upper-left NPTH: X 3.2 mm from the left PCB edge, Y 5.6 mm from the top PCB edge
- Lower-center NPTH: X 35.2 mm from the left PCB edge, Y 21.0 mm from the top PCB edge
- Upper-right NPTH: X 61.8 mm from the left PCB edge, Y 5.4 mm from the top PCB edge
- Drill diameter: approximately 2.75 mm for all three holes
- Visible surrounding mechanical clearance in the source drawing: approximately 5.5 mm diameter
The left/right semicircular features in the hatched region were not converted into drilled slots because their exact physical type is not confirmed. The existing hatched/mechanical keepout is preserved where practical.
Fabrication status: All three hole centers and their shared 2.75 mm provisional diameter remain MECHANICAL VERIFICATION REQUIRED. The type and exact dimensions of the left/right semicircular board-edge features must also be checked against an original board before fabrication.