 The first low-cost junction transistor available to the general public was the CK722, a PNP germanium small signal unit introduced by Raytheon in early 1953 for $7.60 each.In the 1950s and 1960s, hundreds of hobbyist electronics projects based around the CK722 transistor were published in popular books and magazines.Raytheon also participated in expanding the role of the CK722 as a hobbyist electronics device by publishing "Transistor Applications" and "Transistor Applications- Volume 2" during the mid-1950s.