Dec 10, 2019 · Updated on December 10, 2019 - New Active vs. Passive Infographic. Introduction. There are two kinds of RFID systems that exist- passive and active. If you're new to RFID, you might be wondering what the difference is between these types, and which one is best for your application. If you're really curious about the nitty-gritty internal details of I2C and SPI, you might want to read the source code of Wiring Pi, which you can clone from here. Additionally, you can learn about the Linux underpinnings of these interfaces documented at kernel.org. The SPI documentation seems to be more complete than its I2C sibling. Convert external hard drive to GPT without destroying any data by using AOMEI Partition Assistant AOMEI Partition Assistant is a good software that can convert MBR to GPT without destroying any data. Even there are many data on the external hard drive, you can convert it to GPT, which breaks out the limitation of Windows built-in tool. Mobile vs fixed, HF vs VHF, stand alone tracker, digipeater, gateway--there are many ways of using a TNC. Some people act as if choosing a TNC was akin to choosing a religion. I have used all brands of TNC's, and have found they all work well. The differences are mostly in the features, and that is what this page will concentrate on.