Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
CA828939A
Inventor
E. Birt David
F. Sivyer Raymond
S. Webley Reginald
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electrical and Musical Industries Ltd
Original Assignee
Electrical and Musical Industries Ltd
Publication date
Application grantedgrantedCritical
Publication of CA828939ApublicationCriticalpatent/CA828939A/en