I got a new SDR and my LCD computer monitor really creates some interference. When I turn off the monitor, the interference goes away. Monitor is connected via serial type cable.
My SDR has one cable, its a USB that goes to the computer. I obtained 4 toroid ferrites, stacked them, and wrapped the USB cable about 8 times around them. This made the noise go down a lot. And it refined the noise.
The noise appears in 60hZ increments.
I use an 8-plug surge protector on my computer. If I plug the monitor and computer directly into the wall socket the noise is still there.
Is this a ground loop? How can I alleviate this? Thanks.