These recorders were installed in Aeradio around 1960s as a record of air traffic conversationsNot certain if these units were installed at Nhill10 channel Magnetic Tape Recorder, has two recording decks each with two 12" spools containing 3600' 1/2" tape Has power supply and monitor with amplifier and speaker. Includes several spare spools and instructin manual. Model No. TR1710 10 Channel Magnetic Tape Recordertape recorder, aeradio