Abstract: An explosion-venting door structure includes a doorframe having a top rail, a middle rail, and a bottom rail, a first door panel, which has a top mounting flange hinged to the bottom side of the top rail and a beveled bottom edge matching a beveled top edge of the middle rail, and a second door panel, which has a top mounting flange hinged to the bottom side of the middle rail and a beveled bottom edge matching a beveled top edge of the bottom rail.

Abstract: An electronic service reminder to automatically notify a user as to when and what type of maintenance should be performed on the garage door operator, based on a variety of factors, including time, materials and operating environment. The garage door operator is configured to automatically generate an electronic service reminder in the form of an audible or visual alert based on one or more operating parameters of the garage door operator meeting or exceeding a predefined threshold. The predefined threshold is variable based on the values of the operating parameters.

Abstract: A movable barrier operator (10) has a wireless status condition data transmitter (15) that wirelessly transmits status condition messages to one or more remote peripherals (20). The latter can in turn use this status information to effect their own functionality and supported features.

Abstract: A garage monitoring system for use with an automatic garage door opening mechanism that includes a carbon monoxide detector configured to sense the presence of carbon monoxide within the garage and generate an audible alarm when carbon monoxide reaches a predetermined level in the garage. A heater is positioned adjacent the carbon monoxide detector for maintaining the carbon monoxide detector above a minimum operational temperature. The garage monitoring system further includes a garage door position sensor for determining the position of the garage door and generating a signal corresponding to the position of the garage door.

Abstract: A method, system and computer program product for adaptively tracking the position of an entry portal, such as an automatic garage door. In accordance with the present invention a transmitter assembly senses and transmits the sensed position of the door position in a periodic manner at a predetermined transmit interval. A receiver assembly including a receiver module receives the transmitted door position signals and synchronizes the activation of the receiver module with the transmit interval such that the receiver receives the door position signals transmitted at the predetermined transmit interval. A receiver output indicator is then updated in accordance with the entry portal position determined by the received door position signal.

Abstract: There is described a profiled sash section for a window sash holding a window pane and intended for being installed in an outer frame of a blast resistant window. The sash section includes a main member enabling inter-engagement between the profiled sash member and the outer frame a window pane holding member for accommodating and securing an end portion of said window pane in the profiled sash member, and a reinforcing member designed to support the end portion of the window pane and to transmit blast pressure, if incidentally applied to the window pane, to the main member. For at least partially absorbing blast pressure energy applied to the window pane, the sash section is provided with damping means for deforming up to predetermined limit. Also described is a blast-resistant framework for a casement window, including the window sash assembled from the mentioned profiled sash sections and adapted for rigidly and air-tightly securing the window pane in the holders of the profiled sash members.

Abstract: An MCU determines whether a backlash over a predetermined value exists in a driving system including a motor and a window driving mechanism. Then, when it is determined that the backlash over the predetermined value exists in the driving system, the MCU sets the time passed from the detection of the peak of the number of rotations of the motor to a predetermined additional time as a termination time of a start cancellation period. When it is determined that the backlash over the predetermined value does not exist in the driving system, the MCU sets, as the termination time of the start cancellation period, the time when the rate of change of the number of revolutions of the motor reaches a predetermined value or the time when the rate of change of a motor input ratio reaches a predetermined value.

Abstract: An electrically operated fast-food service window with a plurality of upwardly focused infrared emitter/receivers mounted on the fast-food service window in a manner such that the emitter/receivers emit infrared beams at an angle slightly askew of an imaginary vertical plane. The sensors are used to reliably detect an employee in the immediate proximity of the fast-food service window as the employee bends over the horizontal service shelf adjacent to and attached to the fast-food service window as the employee begins to reach towards a customer. The sensors, although focused towards the interior of a building, do in not detect employees or traffic in the immediate vicinity of the fast-food service window thereby virtually eliminating the unintentional opening of the window. The uniquely oriented sensors are connected to an electric motor operator which opens the window as an employee prepares to deliver merchandise or other items to a customer.

Abstract: A movable barrier operator having a motor controller (10) and motor (11) that control selective movement of a movable barrier (12) also has an obstacle detector (14) that utilizes an automatically determined excess force threshold value to permit reliable detection of an obstacle under a wide variety of operational circumstances, including changing physical circumstances, aging components, temperature variations, and motor runtime. In a preferred embodiment, a characteristic force value for the system is frequently updated as a function of actual measured force requirements (and further compensated, pursuant to various embodiments, with respect to other conditions such as temperature and motor runtime). This characteristic force value is then utilized to determine the excess force threshold value.

Abstract: A method is provided for monitoring and mitigating exhaust gas emitted from a vehicle in a closable structure. A remote monitoring device within the closable structure is trained in response to a training signal transmitted from a remote transmitter device. A remote engine start signal is intercepted within a receiving circuit of the remote monitoring device during an actual remote engine start operation. The exhaust gas emitted from the vehicle is monitored in response to receiving the remote engine start signal. A determination is made if an exhaust gas concentration level is greater than a predetermined threshold. A control signal is transmitted to a mitigation device for mitigating the exhaust gas within the closable structure when the exhaust gas concentration level is greater than the predetermined threshold.

Abstract: A method, system and computer program product for adaptively tracking the position of an entry portal, such as an automatic garage door. In accordance with the present invention a transmitter assembly senses and transmits the sensed position of the door position in a periodic manner at a predetermined transmit interval. A receiver assembly including a receiver module receives the transmitted door position signals and synchronizes the activation of the receiver module with the transmit interval such that the receiver receives the door position signals transmitted at the predetermined transmit interval. A receiver output indicator is then updated in accordance with the entry portal position determined by the received door position signal.

Abstract: A movable barrier operator can use (11) a first technique to prevent an excess application of force during controlled movement of a movable barrier (43) and at least a second technique (12) to similarly prevent an excess application of force during such movement. Both techniques can then be utilized to determine (13) when an application of excess force may nevertheless occur and not be reasonably avoided. In one embodiment, two techniques (21 and 22) can be used to detect force as applied during movement of the movable barrier and such information can be used to determine (23) whether applied force is being reliably indicated. In another embodiment, travel limit information (51), travel information (52) and travel history information (53) are utilized to assess whether normal operation of the movable barrier operator should be over-ridden (54) due to a possibly expression of undue force.

Abstract: A sensor arrangement for monitoring a spatial area of least one motor-driven wing of a door includes a plurality of primary transmitters emitting beams of radiation toward a spatial area, and a plurality of primary receivers arranged to receive radiation from the primary transmitters which is reflected in the spatial area, the receivers generating a signal to actuate the motor driving the wing. A plurality of auxiliary transmitters are arranged next to respective primary receivers and emit auxiliary beams of radiation toward the spatial area, and a plurality of auxiliary receivers are arranged next to the primary transmitters to receive radiation from the auxiliary transmitters. A transmitter emits radiation and a receiver reacts to a reflection of the beam differing in intensity and produces a signal which controls the actuation of the door.

Abstract: An operator system and related methods (10) for sensing forces on a movable barrier (12) includes a motor (52), a trolley (30), and a trolley arm (34) having a first end slidably supported by the trolley (38) and a second end coupled to the movable barrier. The motor moves the trolley arm which in turn moves the movable barrier. A force detection mechanism (68) is coupled to the motor to determine a first component force value applied by the motor. A controller (54) receives the first component force value and determines a detected force value by scaling the first component force value with a second component force value derived from an angular position of the trolley arm's first end with respect to the trolley. The angular position of the trolley arm may be fixed or variable. An angle potentiometer (72) is coupled to the trolley arm to generate an angle signal for use as the second component force value when the trolley arm's angular position is allowed to vary.

Abstract: A movable barrier operator having a motor controller (10) and motor (11) that control selective movement of a movable barrier (12) also has an obstacle detector (14) that utilizes an automatically determined excess force threshold value to permit reliable detection of an obstacle under a wide variety of operational circumstances, including changing physical circumstances, aging components, temperature variations, and motor runtime. In a preferred embodiment, a characteristic force value for the system is frequently updated as a function of actual measured force requirements (and further compensated, pursuant to various embodiments, with respect to other conditions such as temperature and motor runtime). This characteristic force value is then utilized to determine the excess force threshold value.

Abstract: The vehicle security inspection system may include multiple automated detection devices for detecting explosives, weapons, contraband, etc. which may be contained on or within a motor vehicle. The system includes a tunnel or enclosure with a moving conveyor therein. A motor vehicle is driven into the entrance to the enclosure, and conveyed past the series of sensors by the conveyor belt. One or more surveillance cameras may be installed in the enclosure, as well. The various sensors incorporated therein check the vehicle for illegal articles, and the vehicle is released from the enclosure. A control gate may be provided as a door at the exit of the enclosure, and/or as a gate guiding vehicles along their intended route or to a detention area, as appropriate. The system may be provided either as a portable device or as a permanent installation, and/or may be configured as a multiple lane inspection system.

Abstract: A clutch control system for moving an object, such as a vehicle door, lift gate or trunk, compares the motor speed with the object speed and engages the clutch when the motor and object speeds are almost equal. Controlling engagement based on the object and motor speeds ensures smooth transitions into a power assist mode and between the power assist mode and a power release mode without causing clutch shock.

Abstract: Movement of a movable barrier (10) such as, for example, a vertically-dropping fire door, can be controlled in an informed manner and with greater flexibility regarding the manner of movement via, in one embodiment, use of a motor (20) as a generator to resist the downward movement of the barrier. One or more dummy electrical loads (22) can be used in combination with the generator mode of operation to influence the degree of braking proffered by the motor. In various embodiments, one or more sensors (25, 26, 27) can be used to detect local and remote conditions of interest to thereby at least partially inform the barrier movement decision process. A display (90) (or displays) can serve to provide various kinds of information to authorized personnel and an operator control (120) can serve, at least under some operating circumstances, to permit a person to locally cause a closed barrier to move to at least a partially opened position.

Abstract: A device for detecting an obstacle in the opening range of a movable closure element (13), more particularly an electrically powered window pane (13) or sunroof of a motor vehicle (10), comprises a sensor electrode (20), a base electrode (21) spaced away from the sensor electrode (20), and a control unit (40) connected to the sensor electrode (20) and the base electrode (21). The sensor electrode (20) and the base electrode (21) generate an electric field (F) in the opening range of the closure element (13) and are spaced away at a constant distance from each other in a first operational mode. The control unit (40) detects in the first operational mode a change in capacitance caused by the presence of an obstacle in the electric field (F) and providing at least one control signal (Is, Ip) for a drive (50) powering the closure element (13). The device is characterized by high reliability in operation and availability.

Abstract: A device of automated closure, and of locking, comprising a mobile closure or locking element (2), an actuator (3) electrically controllable for the motion of said element, a sensor (4), a programming and control device, the program of which comprises at least a mode of delayed action and a means of transition to that delayed action mode, wherein, when placed in the delayed action mode, the programming and control device delivers a complete closure instruction only on activation of a sensor.

Abstract: A power closure system (40) for a vehicle panel (22, 24) includes position initialization techniques that ensure accurate position initialization. According to this invention, any slack in a coupling (62) between the vehicle panel and a motor (42) for moving the vehicle panel is removed prior to obtaining an initialization position reading when the panel (22, 24) is in a closed position. The inventive arrangement also includes determining a desired torque at which to operate the motor (42) during a position initialization procedure.

Abstract: An extendable astragal system (40) includes a housing (47), an actuating member (48) located in and slidably engaged with the housing (47), and an astragal (50) located in the housing (47) and slidably engaged with the housing (47) and the actuating member (48). A latch mechanism (80) retains the astragal (50) within the housing (47) when an ambient temperature is below a predetermined temperature. The latch mechanism (80) enables sliding movement of the actuating member (48) and resultant movement of the astragal (50) to an extended position outside of the housing (47) when the ambient temperature is at the predetermined temperature.

Abstract: An apparatus for shutting off power to a gate motor is disclosed when the gate to which the gate motor is connected is opened or closed manually. In a preferred embodiment a sensor is activated that immediately shuts off power to the gate motor upon insertion of a crank into a receptacle on a pulley of the power driven gate movement system to commence manual opening or closing of the gate with the crank. Rotation of the crank in the appropriate direction either opens or closes the gate. Power is restored to the gate motor when the sensor determines that the crank has been withdrawn from the pulley.

Abstract: A security entrance system for controlling access from an infeed area (98) to a protected area (100) has a structure (24) defining a chamber disposed between the infeed area, the protected area and a temporary containment area (201), with a first door (38) at the infeed area portion of the chamber, a second door (46) at the protected area portion of the chamber, and a third door (47) at the temporary containment area portion of the chamber. A person entering the protected area must pass through a contraband detector such as a metal detector (90,92) and enter the chamber. If no alarm was provided by the detector, the doors allow exit from the chamber into the protected area. If an alarm was provided by the metal detector, the doors only allow the person to enter the temporary containment area. The chamber is weighed or otherwise examined after at least some cycles of operation to assure that no contraband was concealed within the chamber.

Abstract: The invention relates to a decompression unit for equalizing an explosive air pressure between pressurized areas of an aircraft, which have different air pressure conditions and are separated by a wall structure. An air chamber, whose shape alters by contraction (1), is located inside an exterior zone of the cabin (6) and is subjected to an ambient air pressure (p1), said chamber constituting the decompression unit in concrete terms. The wall of the air chamber (1) is perforated. The air chamber is mounted in the vicinity of the periphery of an air pressure equalization flap (2), which is fixed inside an air equalization cavity (9). Said air chamber is connected to a locking device (4), which likewise fixes the air pressure equalization flap in the air equalization cavity.

Abstract: An electronic service reminder to automatically notify a user as to when and what type of maintenance should be performed on the garage door operator, based on a variety of factors, including time, materials and operating environment. The garage door operator is configured to automatically generate an electronic service reminder in the form of an audible or visual alert based on one or more operating parameters of the garage door operator meeting or exceeding a predefined threshold. The predefined threshold is variable based on the values of the operating parameters.

Abstract: A drive system for closing devices, for example gates or shutters, with a variable speed output drive and a device for detecting a given characteristic of the drive, and is varied to maintain a substantially constant speed of the closing device as it moves between the open position and the closed position.

Abstract: An apparatus for shutting off power to a gate motor is disclosed when the gate to which the gate motor is connected is opened or closed manually. In a preferred embodiment a sensor is activated that immediately shuts off power to the gate motor upon insertion of a crank into a receptacle on a pulley of the power driven gate movement system to commence manual opening or closing of the gate with the crank. Rotation of the crank in the appropriate direction either opens or closes the gate. Power is restored to the gate motor when the sensor determines that the crank has been withdrawn from the pulley.

Abstract: A method and an apparatus for testing the unlatching torque of a cassette pod door in order to determine whether a cassette pod door is completely unlatched by latch keys of a door opener in a loadport. When a failure of unlatching operation is indicated, the apparatus reverses the rotational direction of the DC motor and thus, turning the latch keys in an opposite direction to re-latch the cassette pod door onto the cassette pod so that the pod can be securely removed from the loadport without danger of accidental opening of the door.

Abstract: The present invention distinguishes door closing actions between the one effected when an object leaves a prescribed area (i.e. the door closing action resulting from “signal discontinuation due to the exit of an object”) and the one effected when an object remains stationary within the area for a certain period of time (i.e. the door closing action resulting from “forced signal discontinuation in the presence of a stationary object”). Regarding the latter case, the present invention protects a person who stops in the area, by setting the door to close at a low speed and/or issuing a vocal warning. This door closing action can reduce the risk of hitting the person with the door.

Abstract: In a door closing procedure, an aircraft passenger door is pivoted from an open position to a pivoted-in position, shifted to a closed position, locked into a locked condition, and then secured into a secured locked condition. A control method and arrangement for controlling the closing procedure includes sensors that respectively each sense the completion of a respective allocated one of the steps of the closing procedure, and then responsively initiate the next following step of the procedure. The closing procedure is carried out in an automatic sequential step-wise manner using a simple robust arrangement, without requiring a computer control.

Abstract: A seismic sensor controlled door unlocking system which has a vibration sensor and a control system. The vibration sensor is configured to detect heavy vibrations such as those made by an earthquake. The control system maintains the locked state of, and has the ability to unlock, a door to which it is connected. Upon detection of a large vibration by the vibration sensor, the control system unlocks the door.

Abstract: The invention relates to a method and an arrangement for driving door installations as a function of the presence of person wherein the region of the door installation is continuously observed by at least one videocamera. According to the invention through the videocamera and/or suitable sensors, object motions within the space to be monitored are acquired with an analysis being carried out in conjunction with the video image of whether or not the moving object is a person. If this is the case, its location and/or direction of movement is determined and the door installation is driven as a function thereof. The videocamera is preferably disposed approximately diametrically opposite the door installation with its angle of view being directed as steeply as possible onto the region to be monitored. The videocamera is connected to an electronic image processing device.

Abstract: A security entrance system for controlling access from an infeed area (98) to a protected area (100) has a structure (24) defining a chamber disposed between the infeed area and the protected area, with first doors (38) at the infeed end of the chamber and second doors (46) at the protected area end of the chamber. A person entering the protected area must pass through a contraband detector such as a metal detector (90, 92) and enter the chamber. If no alarm was provided by the detector, the doors allow exit from the chamber into the protected area. If an alarm was provided by the metal detector, the doors only allow the person to pass back from the chamber into the infeed area and away from the protected area. The chamber is weighed or otherwise examined after at least some cycles of operation to assure that no contraband was concealed within the chamber.

Abstract: An access device for a materials depository includes a panel member having opposing front and rear faces with a return aperture disposed therethrough, a door having size dimensions capable of fully blocking the return aperture, and a door actuator coupled to the door for causing the door, in response to a command signal, to selectively slide between a blocking position where the return aperture is blocked by the door, and an unblocking position where the return aperture is not blocked by the door. The access device also includes a materials sensor for providing a materials alarm signal that is indicative of a presence of materials intended to be passed through the return aperture. The access device further includes a control system that is responsive to the materials alarm signal, for providing the command signal.

Abstract: A control method of sliding a vehicle door by a powered sliding device with a clutch mechanism comprises the steps of stopping a motor in a state that a rotation of a wire drum is restricted by an auxiliary brake when the slide door reaches at a desired semi-open position; displacing the clutch mechanism into a second coupled state by the motor while the auxiliary brake is actuated; releasing the restriction by the auxiliary brake when a predetermined time has elapsed.

Abstract: A movable barrier operator having improved safety and energy efficiency features automatically detects line voltage frequency and uses that information to set a worklight shut-off time. The operator automatically detects the type of door (single panel or segmented) and uses that information to set a maximum speed of door travel. The operator moves the door with a linearly variable speed from start of travel to stop for smooth and quiet performance. The operator provides for full door closure by driving the door into the floor when the DOWN limit is reached and no auto-reverse condition has been detected. The operator provides for user selection of a minimum stop speed for easy starting and stopping of sticky or binding doors.

Abstract: A maintenance station monitors and maintains a plurality of automatic door systems at remote locations. Each door system includes a control unit for controlling the operation of an automatic door, and a self-diagnosing arrangement which operates in conjunction with the control operation of the control unit, to inspect the automatic door system for malfunctioning or broken part of the door system. When a failure is found in the automatic door system, the self-diagnosing arrangement of that door system sends information identifying that door system and information identifying the malfunctioning or broken part to the maintenance station via modems and telephones.

Abstract: The invention relates to a sliding door with two outer side-pieces extending from a building wall and surrounding a building entrance/exit, with at least one moving panel associated with the two side-pieces which closes or opens an entrance/exit as a result of its movement into a closed or open position, and with a ventilation system which, by means of at least one blower nozzle that is located so that it can pivot between the interior and exterior of the building, blows air into the building entrance/exit area, whereby the blower nozzle is coupled with a air speed indicator so that the pivoting angle of the blower nozzle can be adjusted as a function of the outside pressure on the outside of the building as measured by the air speed indicator.

Abstract: The invention relates to a device for preventing insertion from the outside of instruments that could pivot the control bar situated on the inside of the skylight. The device is constituted by a box and two narrow strips positioned in an offset manner so as to form a baffle preventing any instrument being inserted while leaving a free passage for ventilation air. Spacers serve to stiffen the assembly. A cap protects the control lever for opening the lock of the skylight, and a fork enables the latch existing on the skylight to be moved.

Abstract: A platform sensing and control system including a wireless sensor (10, 12) for sensing at least the presence of a platform (26) opposite a door (32) of a railcar and providing an output indication of at least a platform presence in response thereto, and a door control controller (14) operative in response to the output indication of at least platform (26) presence for enduring that normally a door (32) is not opened other than when a platform (26) is located opposite such door (32).

Abstract: A movable barrier operator includes a wall control switch module having a learn switch thereon. The switch module is connectable to a control unit positioned in a head of a garage movable barrier operator. The head unit also contains an electric motor which is connected to a transmission for opening and closing a movable barrier such as a garage door. The switch module includes a plurality of switches coupled to capacitors which, when closed, have varying charge and discharge times to enable which switch has been closed. The control unit includes an automatic force incrementing system for adjusting the maximal opening and closing force to be placed upon the movable barrier during a learn operation. Likewise, end of travel limits can also be set during a learn operation upon installation of the unit.

Abstract: A collapsible panel forming a separation structure between a generally closed inner environment and an outer environment, for instance consisting of a motorvehicle stratified window, incorporating within its mass at least one explosive charge to which an igniter/detonator device is operatively associated to produce detonation of the explosive charge so as to shiver the panel in a controlled way substantially within the plane thereof.

Abstract: The invention concerns a drive for closing devices, for example gates or shurrers, with variable speed output drive and a device for detecting a given position of the closing device. According to the invention, the drive speed output depends on the position of the gate and can be controlled depending on the given mechanical closing characteristic of the closing device.

Abstract: An automatic-shutter system functions as a counter-measure to the in-band frequency agile laser threat posed to the eyes of pilot(s)/operator(s). Ideally it is desirable to protect the operator from every laser pulse including the first. However, the lack of fast shutters or optical gates (faster than a micro-second) suitable for visible usage has prevented the protection from a first pulse threat. The automatic-shutter system detects the first pulse and provides protection against any subsequent pulses. This is achieved by a multi-directional detector system for actuating shutters on the aircraft/vehicle. The detector, after detecting a pulse of laser light, further comprises processing means in electrical communication with the multi-directional detector for processing a detected pulse of laser light and to generate a signal responsive thereto. A plurality of shutters can be individually or group dropped in response to shutter actuating means to provide protection against subsequent pulses of laser light.

Abstract: A power drive system is adapted for a sliding door mounted on at least one side of a vehicle for sliding movement forwardly and rearwardly of the vehicle. The system includes a reversible motor. A bracket is guided within a guide along a fixed path between the opened and closed positions of the door. An elongated drive member is slidably disposed within the guide and connected to the bracket at one end for driving the bracket along the fixed path. A translator mechanism operably engages with the drive member for powering movement of the door. The translator mechanism can include a rotatable hub, operably engageable with the drive member, a gear transmission for driving the hub, and a clutch mechanism for connecting the motor to the transmission. The translator mechanism preferably has sufficient power to pull the sliding door into a primary latch position with respect to the corresponding portions of a latch mechanism attached to the door and frame defining the door opening.

Abstract: An improved motor vehicle roof is provided which includes a roof opening provided in a fixed roof surface, at least one closing element for selectively at least partially closing the roof opening, an electrical adjusting drive for driving the closing element and a sensor engineering system for detecting a situation which adversely affects the safety of the passengers and for producing a corresponding danger signal. Importantly, the roof includes a quick-action closing device coupled to the sensor engineering system which causes the closing element to close from its open or partially open position when a danger signal is present. The closing device includes means for producing an electrical voltage which exceeds the normal feed voltage (rated voltage) of the adjusting drive by several times, and for applying the voltage to the electric adjusting drive.

Abstract: Method and apparatus for automatically controlling the opening and closing of a door by: (a) ultrasonically monitoring a predetermined approach area located in front of the door for the entry of an object into the approach area and the movement of the object towards the closed door; (b) ultrasonically monitoring a predetermined opening-door protect area laterally outwardly of the outer end of the closed door, and a predetermined closing-door protect area inwardly of the inner end of the door for the presence of an object in the opening-door and closing-door protect areas; and (c) controlling a drive in response to the above monitoring operations.

Abstract: A movable barrier operator having improved safety and energy efficiency features automatically detects line voltage frequency and uses that information to set a worklight shut-off time. The operator automatically detects the type of door (single panel or segmented) and uses that information to set a maximum speed of door travel. The operator moves the door with a linearly variable speed from start of travel to stop for smooth and quiet performance. The operator provides for full door closure by driving the door into the floor when the DOWN limit is reached and no auto-reverse condition has been detected. The operator provides for user selection of a minimum stop speed for easy starting and stopping of sticky or binding doors.

Abstract: A movable barrier operator system includes a barrier-motor electrical driver, a first input device for receiving operating commands, a second input device for developing system status and a controller for storing a record of all input commands received and a record of all events occurring to the movable barrier and for enabling operation of the electrical driver in response to an input command. The first input device may be a DTMF receiver or a telephone entry system. Events stored include barrier obstructions and barrier operator failures. The controller, responsive to a stored event, enable the telephone entry system to contact a service provider. For facilities with multiple barriers and a DTMF receiver at each operator, a special circuit normalizes the amplitude of a transient analog tone burst (such as from a DTMF transmission) without any transient level overshoot.