This log describes the recommended assembly instructions for the Buoy A V1.0 PCB. The following image shows all the required components, with an identification number that will be used in the log.

Components List:

1. ESP32-DEVKITC-32D
2. TB6612FNG MOTOR DRIVER BOARD
3. CONN HDR 5POS 0.1 GOLD PCB
4. CONN HEADER VERT 3POS 2.54MM
5. CONN HDR 6POS 0.1 TIN PCB
6. CONN HDR 8POS 0.1 TIN PCB
7. CONN HDR 8POS 0.1 TIN PCB
8. CONN HDR 8POS 0.1 TIN PCB
9. CONN HDR 19POS 0.1 TIN PCB
10. CONN HDR 19POS 0.1 TIN PCB
11. Buoy A V1.0
12. CONN HEADER R/A 3POS 2.5MM
13. TERM BLK 3P SIDE ENT 5.08MM PCB
14. TERM BLK 2P SIDE ENT 5.08MM PCB
15. CONN HDR 9POS 0.1 GOLD PCB
16. CONN HDR 9POS 0.1 GOLD PCB
17. 2 CONN HDR 2POS 0.1 GOLD PCB
18. CONN HDR 9POS 0.1 GOLD PCB
19. CONN HDR 10POS 0.1 TIN PCB
20. CONN HEADER VERT 3POS 2.54MM
21. Adafruit Ultimate GPS
22. RFM95W LoRa Radio
23. SIM7600CE-T 4G(LTE) Arduino Shield

It is possible to solder the components in many different orders, I'll describe the one that I followed, it can used as a reference.

Instructions

a.Solder the female headers 9 and 10 used to connect the ESP32-DEVKITC-32D to Buoy A V1.0.

b.Solder the female headers 7 and 8 used to connect the TB6612FNG MOTOR DRIVER BOARD to Buoy A V1.0.

c. Solder the female header 17 to Buoy B V1.0.

d. Solder the 3POS Horizontal JST-XH connector (12).

e. Solder the male header 4.

f. Solder the female headers 3 and 16 used to connect the RFM95W LoRa Radio to Buoy A V1.0.

g. Solder the female headers 15, used to connect the Adafruit Ultimate GPS to Buoy A V1.0. 

i. Solder the male connector 20 to Buoy A V1.0. 

j.Solder the female headers 5, 6, 18 and 19 used to connect the SIM7600CE-T 4G(LTE) Arduino Shield to Buoy A V1.0.

k. Solder the terminal blocks 13 and 14 to Buoy A V1.0.