You all know how much current can be delivered by a Li-ion battery: it is many times what you need to burn your rig. So, like me, you are using fuses.
But what will you do when the fuses are gone on top of the SOTA peak? or after a 5 hour hike? Yes, you have spare ones but you know that usually you will find the wiring issue causing the fuse to go only when the latest one is gone 🙂
A Polyswitch resettable fuse is the solution: it costs only half a dollar, and SMD’s are only 0.4 in. by 0.1 in. I took some 1.25A/250v for my Mountain Topper Radio as shown here:
What you have to do is just to cut a small piece of PCB, cut the copper on each side to isolate the 2 ends. Solder a Polyswitch SMD and the wires on both side and finish with some heat-shrink tube with glue to protect it against moisture.