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English: Christian Lindberg valve in default (A) and engaged (B) positions. 1. airflow, from mouthpiece; 2. airflow, to bell; 3. valve tubing; 4. valve casing; 5. internal rotor; 6. valve ports; 7. spindle. Simplified illustration based on patent diagrams. US Patent 5965833 (1999) assigned to C.G. Conn, marketed on Conn trombones as the "CL2000" valve.
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Author
Jonathan Harker
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