[limpkin] writes us to show a line injector they’ve designed. The principle is simple — if you want to measure how much PSU noise any of your electronic devices let through, known as PSRR (Power Supply Rejection Ratio), you can induce PSU noise with this board, and then measure noise on your device’s output. The board is likewise simple. A few connectors, resistors, and caps, and a single N-FET!
This is a companion discussion topic for the original entry at https://hackaday.com/2024/04/05/a-simple-line-injector-shows-you-the-wonderful-world-of-psrr/