Chapter 2 — Building GPS Data Cables and Power Cords

39

If you don’t, then you must have the wrong settings. Go back and try some alternative settings. Once you can successfully see data, you know it’s working right.

Making Combo Cables

By now you’ve probably figured out how to make combo cables. First make one cable and then attach the other kind of cable to the spare pins, joining them together. It’s really quite simple.

Many people seem confused about what to do with the two grounds that they end up with (a data ground and a power ground). The answer is simple: connect them together. That configuration works perfectly.

Another question that people have is how they should join the two cables together robustly, so as not to strain the joints. Over the years, I’ve found the best solution involves a combination of tape (both electrical and duct tape), followed by a few well-placed plastic ties (to take the strain). Another way to keep cables under control is to use a strip of shrink wrap.

Note that if you are making a combo cable, keep an eye on the wiring and make sure that it is both tidy and sound, as the last thing you want is a wire coming loose and causing a short circuit that could kill your GPS receiver.

Making Multi Cables

By now you also probably know how to make a multi-ended cable. All you need are the appropriate connectors and enough wire. The more you add, the more complex the cable will look, so you will need to keep track of which wires and parts go where — the last thing you want to end up with is a cable with a GPS connector at both ends (unless, that is, you want to transfer data between two GPS receivers).

I would suggest that for more complex cables, you make detailed notes and use your multimeter regularly during construction of the cable to ensure that everything works right.

Summary

This chapter has been all about cables — types of cables, making cables, and using cables. It’s amazing what you can do with a GPS unit on its own, but add a cable and a PC or mobile device to the equation and the horizons really open up! In addition, GPS receivers need a lot of power, so making a cable that enables you to save a little battery power when you are in the car is always welcome. This enables you to save the battery power for when you are on foot and away from a 12-volt supply. In the next chapter, you’ll find out that you are never too far away for a 12-volt supply, no matter where you are!

Have fun creating custom cables!