If someone installs a pinhole or a monitor at home, will it affect the cell phone signal or something? How can we find it and find it?

No, because the transmission frequencies of various devices are different. The frequency of wireless routing and wireless mouse is 2.4GHz, the frequency of walkie-talkie is between 400 and 500 MHz, and the working frequency of wireless camera is generally 1200MHz, which are not in the same frequency band and will not cause interference. You might as well buy a professional detector, such as a hound detector, and you can find the hidden camera in ten minutes. I have a deep understanding of this. I used to take a netizen to stay in a hotel and was photographed and blackmailed, and finally spent money to eliminate disasters. Later, I got scared and bought a hunting dog detector with a micro-pattern net. Every time I stay in a hotel, I always check it out first, and then nothing happens.