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Contact Information:

Resources:

dbx Professional Products

8760 South Sandy Parkway
Sandy, Utah 84070
Phone: (801) 568-7660
Fax: (801) 568-7662

Web: http://www.dbxpro.com/
Email: support@dbxpro.com

 

THAT Corp: A Brief History of VCA Development

History:

Patents:

Founded: 1971 by David Blackmer

Sold to BSR in 1979

 

 

* U.S. Patent No. 3,714,462, 01/30/1973: Multiplier Circuits Blackmer, David E. [ abstract ] [ DjVu 82 KB ]

U.S. Patent No. 4,234,804, 11/18/1980: Signal correction for electrical gain control systems Bergstrom, Gary (assignee dbx, Inc.) [ abstract ] [ DjVu 198 KB ]

U.S. Patent No. 4,331,931, 05/25/1982: Gain control systems Adams, Robert W. (assignee dbx, Inc.) [ abstract ]
[ DjVu 126 KB ]

U.S. Patent No. 4,403,199 , 09/06/1983: Gain control systems Blackmer, David E. (assignee dbx, Inc.) [ abstract ]
[ DjVu 179 KB ]

U.S. Patent No. 4,454,433 , 06/12/1984: Multiplier circuit Welland, David R. (assignee dbx, Inc.) [ abstract ]
[ DjVu 100 KB ]

Unprocessed Patents

4,101,849 Blackmer & Jaeger Adaptive filter
4,112,254 Blackmer Signal compander system
4,124,784 Johnson, Blackmer & Mosely Motion picture sound system
4,136,314 Blackmer & Jaeger Adaptive signal weighting system
4,177,356 Jaeger & Blakely Signal enhancement system
4,182,930 Blackmer Detection and monitoring device
4,182,993 Tyler Signal amplitude compression system
4,220,929 Talbot & Blackmer Signal expander
4,316,060 Adams & Tyler Equalizing system
4,316,107 Talbot Multiplier circuit
4,329,598 Welland Bias generator
4,368,425 Adams System for and method of testing transistors
4,377,792 Blackmer & Welland Compander system
4,409,500 Welland Operational rectifier and bias generator
4,425,551 Blackmer & Welland Differential amplifier stage having bias compensating means
4,430,626 Adams Networks for the log domain
4,434,380 Welland Compensation for VCA OP amp errors
4,445,053 Jaeger & Seale Square law charger
4,467,287 Aylward Signal expander
4,471,324 Welland All NPN variably controlled amplifier
4,473,793 Blackmer & Welland Bias generator
4,503,553 Davis Loudspeaker system
4,503,554 Davis Stereophonic balance control system
4,539,526 Davis Adaptive signal weighting system
4,588,979 Adams Analog-to-digital converter

 

Alumni:

 

Adams, Robert W.

Aylward, Joseph R.

Blackmer, David

Blakely, Lawrence E.

Davis, Mark F.

Jaeger, C. Rene

Johnson, Keith O.

Mosely, John deS.

Purple, Dave

Seale, Joseph B.

Stiernberg, John

Talbot, Daniel B.

Tyler, Leslie B.

Welland, David R.

 

 

 

 

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