I’ve learned this solution during my 1-year stay at the Signal Processing Laboratory of the University of the Algarve as an R&D engineer. The trick is to always have a common connector in every cable that you do, which can be of several types, such as BNC, RCA or others. Besides the connectors you will also need to have the junction connectors.
- Cut a cable containing a USB A connector on one end;
- Solder a male RCA connector to the VDD and GND wires of the cable with the USB A connector. As a rule, always put the VDD in the middle pin and the GND on the outside;
- Get the cable with the barrel connector and solder a male RCA connector to the other end. Once again, VDD in the center pin and GND in the outside;
- Now that you have both cables with RCA endings, you can connect them using a Female to Female RCA junction.
If you always do this to all the leftover cables that you can get, you’ll be able to do any cable to power your devices in no time, since you’ll only have to unplug one end and connect it to another cable 🙂 . This way, you won’t have to make a new cable for every single combination of connectors that you can imagine. If you want, you can also use two junctions and put an extension cable in middle 🙂 .