Caladena Group fabricated a four-layered PCB for Defence R&D Canada. We also needed to use a special heating process to mount a GPS module (BGA chip).

The following is an exerpt from:

Defence R&D Canada – Valcartier Technical Report

DRDC Valcartier TR 2005-272; January 2007

Page 33 of - Design and test results of AMIGO: A novel remote ground sensor system (U) PCB design and fabrication.

"The design and fabrication of the final PCB was done using Protel 98 SE. The schematics

shown in Annex A.1, A.2, and A.3 are the final circuit of the system. From these three

schematics, a four-layered PCB was fabricated by Caladena Group.

Most components on the PCB are surface-mounted. With the exception of the GPS module,

they were mounted by DRDC personnel. The GPS module is a BGA chip that must be

mounted on the PCB with a special heating process. This was performed at Caladena.

The resulting PCB with all the parts soldered and major bugs corrected is shown in Figures 16

and 17. As the photos show, minor bugs in the original design were corrected with wirewrapped

cable. Most bugs were corrected on the final schematic as well.

Figure 17. AMIGO PCB (top side)"

(Figure 17 shown here)