The staff records interviews using Marantz PMD661 digital recorders and Audio Technica AT835b shotgun microphones. It includes digital voice recorders and tape recorders. Included to allow connection with televisions, DVD players, video recorders and video game consoles. Akai produced consumer video cassette recorders (VCR) during the 1980s. In the 1990s, some boomboxes were available with minidisc recorders and players. This allowed the MiniDisc to better compete with HD recorders and MP3 players. Operators typically monitored charts drawn by recorders that plotted data from instruments. The higher capacity is incompatible with some recorders and recording software. Around age 9, diatonic recorders and orchestral instruments are introduced. Fan videos made using videocassette recorders soon followed. Sony began producing popular magnetic tape recorders for government and public use. There are many tape speeds which are in use in all sorts of tape recorders. Measurement is performed by instruments called sunshine recorders. In the past magnetic or DAT tape recorders were used. Most contemporary tape recorders use AC bias.