- Key fob only works on battery and not power supply. What's going on here?
Yesterday the batteries died on my key fob and I didn't have the appropriate batteries to replace them. I thought I could use my power supply to operate the key fob to open the car door but it did not work. I thought that it may be caused by a noisy power supply at the higher frequency range of 432MHz but when I got my hackRF to investigate the waveform with the battery and then with the power supply, I was shocked to find no signal at all. I have since replaced the batter and everything works great, but as a recently graduated EE I am at odds with what is going on. Can anyone help me figure out this mystery. Here is a youtube link of the issue