As with radio in general, amateur radio was associated with various amateur experimenters and hobbyists. They are discovered by observers or experimenters. Many experimenters in this band are amateur radio operators. Three subjects were eliminated because they failed to comprehend the instructions given by the experimenters. Six subjects were eliminated because they failed to comprehend the instructions given by the experimenters. The procedures were conducted by two male experimenters. Those who were approached by higher-strength experimenters were more likely to contribute money. Other experimenters tried a variety of other minerals as detectors. Other experimenters, including Elihu Thomson and Nikola Tesla, also reported burns. There are various factors not considered by experimenters while implementing the theory. Early vacuum experimenters found a rather surprising behavior. Speaking later that month, Gernsback downplayed the broadcasts, intended for amateur experimenters. The experimenters placed placard in campus toilets to discourage graffiti. This has largely been due to lack of replication of results by independent experimenters. Through February there were 46 experimenters taking up the technique in North America alone.