Patents Assigned to Roberts Retrovalve, Inc.
  • Patent number: 7482863
    Abstract: Methods are provided for solid-state implementation of a vacuum tube replacement device that supplements the functional performance of the target replacement device, i.e., a traditional glass vacuum tube. Example functions may include OEM or user adjustable parameters such as gain and/or frequency response (e.g. transfer function), current and/or voltage saturation thresholds, bias condition, input and/or output impedance, linear-to-non-linear transfer function(s) (e.g. soft clipping parameters), power dissipation, communication protocols, and audio/visual indication parameters such as signal limiting detection, safety, stress, or wear-out conditions, and tube emulation model type to name a few. The methods presented for the vacuum tube replacement device system(s) are equally useful for non-vacuum tube systems such as audio amplifier circuits.
    Type: Grant
    Filed: August 9, 2007
    Date of Patent: January 27, 2009
    Assignee: Roberts Retrovalve, Inc.
    Inventors: Douglas H. Roberts, Brett A. Hertzberg
  • Patent number: 7408401
    Abstract: A system is provided for a solid-state implementation of a vacuum tube replacement device. The system may derive power from a target amplifier filament supply. The system may include active or passive functions for noise reduction, voltage isolation, servo biasing, and other functions. The vacuum tube replacement device is pin-for-pin compatible with standard vacuum tube circuit pin configurations. The vacuum tube replacement device system architecture is equally useful for non-vacuum tube systems such as audio amplifier circuits.
    Type: Grant
    Filed: February 23, 2007
    Date of Patent: August 5, 2008
    Assignee: Roberts Retrovalve, Inc.
    Inventor: Douglas H. Roberts
  • Publication number: 20070285156
    Abstract: Methods are provided for solid-state implementation of a vacuum tube replacement device that supplements the functional performance of the target replacement device, i.e., a traditional glass vacuum tube. Example functions may include OEM or user adjustable parameters such as gain and/or frequency response (e.g. transfer function), current and/or voltage saturation thresholds, bias condition, input and/or output impedance, linear-to-non-linear transfer function(s) (e.g. soft clipping parameters), power dissipation, communication protocols, and audio/visual indication parameters such as signal limiting detection, safety, stress, or wear-out conditions, and tube emulation model type to name a few. The methods presented for the vacuum tube replacement device system(s) are equally useful for non-vacuum tube systems such as audio amplifier circuits.
    Type: Application
    Filed: August 9, 2007
    Publication date: December 13, 2007
    Applicant: Roberts Retrovalve, Inc.
    Inventors: Douglas Roberts, Brett Hertzberg
  • Patent number: 7286060
    Abstract: A vacuum tube replacement device includes an indicator. The indicator can be arranged to provide audible and/or visual indication of system performance, function, status, or any other desired indication. The vacuum tube replacement device is pin-for-pin compatible with standard vacuum tube circuit pin configurations. The replacement device may be a solid-state tube emulator device, a traditional glass envelope vacuum tube device, or some other hybrid device. The visual indicator is equally useful for non-vacuum tube replacement devices such as audio amplifier circuits.
    Type: Grant
    Filed: August 12, 2005
    Date of Patent: October 23, 2007
    Assignee: Roberts Retrovalve, Inc.
    Inventors: Douglas H. Roberts, Brett A. Hertzberg