Funny this should come up as I just came from the field and one of the Pilots was discussing his problem while working in his shop. Now this shop is two hundred feet from the house. This guy was getting all kinds of hits. He has an intercom so he asked his wife if she had turned anything on. To make a long story a little shorter he found that she was using a small (cheaper) paper shreader. When she put paper through it and the shreader started up he was getting al kinds of interference. So, bottom line is yes its possible to get interference. The higher the frequency the more powerful signal is required to cause this interference though.