Abstract: Systems, methods, and probe devices for electronic monitoring and characterization using single-ended coupling of a load-pulled oscillator to a system under test.

Abstract: Diversity reception apparatus includes a number of receivers each having a distortion detector. There is a common output channel. A comparator compares the signals detected by detectors and provides a control signal to a selector or switching circuit that couples that receiver having the preferred received signal to the common output channel.

Abstract: A powered loudspeaker system has a cabinet. The cabinet has at least one electroacoustical transducer and a power amplifier coupled to the electroacoustical transducer. Dynamic equalization circuitry coupled to the power amplifier provides a predetermined desired dynamic equalization for the electroacoustical transducer in the cabinet when normally positioned in a listening room.

Abstract: A duct tape having a non-depositing pressure sensitive adhesive, wherein said duct tape can be removed after application to a surface of a substrate, the duration of the application being indefinitely extended for multiple weeks, without leaving an adhesive residue on the surface of the substrate, where the non-depositing adhesive is a hot melt adhesive based on a SIS Styrenic Block Copolymer rubber having around 40% diblock, that is tackified with an aromatic C-5 resin, and wherein said adhesive has an excellent antioxidant system.

Abstract: A receiver for receiving a stereophonic signal with upper and lower sidebands carrying a modulating signal includes independent sideband circuitry for providing upper and lower sideband signals. Selector circuitry responds to the level of audible noise in each of the upper and lower sideband signals for selecting that one of the sideband signals having a lower level of audible noise relative to the other. An ISB highpass filter filters the latter sideband signal to provide a highpass filtered sideband signal. Stereo detector circuitry provides left and right stereophonic audio signals. At least one audio lowpass filter filters the left and right stereophonic signals to provide corresponding lowpass filtered left and right stereophonic audio signals. At least one signal combiner combines the highpass filtered sideband signal with each of the lowpass filtered left and right stereophonic audio signals to provide corresponding composite left and right audio signals.

Abstract: Apparatus for demodulating information signals frequency-modulated on an RF carrier signal carrying spectral components within the audio frequency range, a pilot carrier signal having an imparted phase shift from the phase of the transmitted pilot carrier signal, and amplitude-modulated spectral components having another imparted phase shift in a subcarrier channel frequency range above the audio frequency range. The apparatus includes a demodulator for demodulating the frequency-modulated information signals to provide a detected composite signal which includes a detected pilot carrier characterized by an imparted phase shift due to the effects of multipath reception, and detected amplitude modulated spectral components exhibiting another multipath induced phase shift.

Abstract: A method and apparatus for reducing the number of errors generated when reading digital data stored on a recording medium such as film, the method comprising passing light of two different frequencies (i.e., two different frequency bands) through the film, one frequency being modulated by digital data stored on the film and the other being unaffected by the stored data. The light that is unaffected by the stored data is modulated by debris on the film such as dirt and is used to flag data bits that may be in error to thereby facilitate an error correction process. In the first disclosed embodiment the two frequencies of light are processed separately to obtain the digital data and error flags. A second embodiment combines all light passing through the film to produce digital information that includes error flags.

Abstract: A system for reducing audible noise in a stereo receiver includes a stereo demodulator having a monophonic signal output and a difference signal output. There is a left signal combiner and a right signal combiner. At least one filter having a controllable variable cutoff frequency intercouples at least one of the difference signal output and the monophonic signal output with the left and right combiners. A control signal generator has a control signal output coupled to the control signal input of the variable cutoff frequency filter.

Abstract: A receiver for receiving a transmitted signal comprising first and second bandwidth limited component signals modulating a single high frequency carrier in phase quadrature with the first component signal as originally transmitted including an identification signal has a source of a reference signal subject to phase error. Circuitry combines the received transmitted component signals with the reference signal to provide first and second demodulated signals characteristic of the first and second component signals respectively. A detector responds to the first and second demodulated signals to provide first and second detected components of the identification signal. Feedback circuitry responds to the detected components of the identification signal by providing a correction signal that is applied to the source of reference signal to reduce the phase error.

Abstract: A system and method for monitoring conditions in a fluid medium. A stream of the fluid medium is flowed through a fluid container which is electrically configured as a transmission line segment and which is electrically connected to load to UHF or microwave oscillator. The oscillator is not isolated from the load, and is operated free-running, at a starting frequency which is chosen to provide a particularly strong shift in permittivity of the fluid medium, as the chemical reaction progresses. Preferably the frequency and insertion loss of the oscillator are monitored, to gauge the progress of the reaction.

Abstract: A receiver for receiving an amplitude modulated signal with upper and lower sidebands, comprising: an independent sideband decoder for providing demodulated upper and lower sideband audio signals, a combiner for differentially combining the upper and lower sideband audio signals to provide a noise signal, a quality detector apparatus for providing upper and lower quality signals representative of undesired noise in the upper and lower sideband audio signals respectively, and a selector responsive to the quality signals for processing the upper and lower sideband audio signals to provide an output audio signal with reduced noise. The quality detector includes a correlator for correlating the noise and audio signal in the associated sideband to provide the quality signals.

Abstract: Marksmanship training apparatus is used with air guns or weapons firing blank cartridges and comprises a housing member with an attached muzzle alignment tube for insertion into the bore of the barrel of the weapon and includes sealing apparatus around the muzzle alignment tube to minimize leakage of gas between the bore and the muzzle alignment tube and to prevent the gas from pushing the muzzle alignment tube out of the bore. The housing member includes a switch which is activated by the gas to complete an electrical circuit positioned in the housing to cause light energy to be emitted from the housing member.

Abstract: A mechanically refrigerated chiller system for a process coolant has a process coolant circuit which includes a coolant reservoir with refrigerant evaporator coils in it. Coolant returns from the process to the reservoir through several and alternate paths. An additional coolant path is provided through a heat exchanger. An extra hot-gas line from the high pressure side of the refrigerant compressor is coupled through the heat exchanger to the refrigerant condenser. When the temperature of the coolant is too low, adjustment is made by adding heat to some of the coolant in the heat exchanger. Coolant temperature is sensed in an area where coolant returns from the process through a direct path and in another area where the coolant is leaving the evaporator through the aforementioned heat exchanger are mixed with a portion of the reservoir coolant.

Abstract: A mechanically refrigerated chiller system for a process coolant has a process coolant circuit which includes a coolant reservoir with refrigerant evaporator coils in it. Coolant returns from the process to the reservoir through several and alternate paths. An additional coolant path is provided through a heat exchanger. An extra hot-gas line from the high pressure side of the refrigerant compressor is coupled through the heat exchanger to the refrigerant condenser. When the temperature of the coolant is too low, adjustment is made by adding heat to some of the coolant in the heat exchanger. Coolant temperature is sensed in an area where coolant returns from the process through a direct path and in another area where the coolant is leaving the evaporator through the aforementioned heat exchanger are mixed with a portion of the reservoir coolant.

Abstract: A mechanically refrigerated chiller system for a process coolant has a process coolant circuit which includes a coolant reservoir with refrigerant evaporator coils in it. Coolant returns from the process to the reservoir through several and alternate paths. An additional coolant path is provided through a heat exchanger. An extra hot-gas line from the high pressure side of the refrigerant compressor is coupled through the heat exchanger to the refrigerant condenser. When the temperature of the coolant is too low, adjustment is made by adding heat to some of the coolant in the heat exchanger. Coolant temperature is sensed in an area where coolant returns from the process through a direct path and in another area where the coolant is leaving the evaporator through the aforementioned heat exchanger are mixed with a portion of the reservoir coolant.

Abstract: An automatic dynamic equalizer includes left and right input terminals, an input adder and left and right output adders. The left and right input terminals are connected to inputs of the input adder and inputs of the left and right output adder, respectively. The output of the input adder is connected to the input of a 2:1 compressor. The output of the 2:1 compressor is connected to the input of a bandpass filter having a transmission in the low bass frequency region centered at a frequency of about 60 Hz. The output of the bandpass filter is coupled to inputs of the left and right output adders.

Abstract: Marksmanship training apparatus which provides for simulated firing of projectile-type weapons is disclosed and comprises a substitute cartridge and a receiver/detector target device. The substitute cartridge is self contained and includes a power source, an energy emitting device which emits a pulse or pulses or energy with predetermined characteristics, a lens device to concentrate the emitted energy, an energy activation device and a transfer device to transfer the energy from the firing mechanism of the weapon to the energy activation device to activate same. The receiver/detector target device includes devices to detect the presence of the pulse or pulses of energy while ignoring the ambient light level surrounding the target device. The target device initiates a time cycle and provides a display of the elapsed time from initiation to the receipt of a hit from the pulse or pulses of energy emitted from the substitute cartridge in the weapon. An audio indication is also provided when a hit occurs.

Abstract: A loudspeaker driver has its front surface adjacent one end of a low loss acoustic waveguide and its rear surface adjacent to one end of a second acoustic waveguide that is one third the length of the first. The other openings of the waveguides face air and couple acoustical energy substantially uniformly over a relatively broad range of frequencies extenting into the bass frequency region. An equalizer includes a notch filter so that the frequency response of the equalizer below a bass cutoff frequency is sufficiently low to prevent audible distortion.

Abstract: Photosensitive flexographic element comprising(A) a flexible support,(B) a photosensitive elastomeric layer comprising (a) butadiene/acrylonitrile copolymer having a no. average molecular weight of 20,000 to 75,000 and optionally up to 15% by weight carboxyl content, (b) ethylenically unsaturated monomer and (c) free radical generating system, and between (A) and (B) an adhesive blend of at least two of the following polymers (1) polyester resin, condensation polymer of ethylene glycol, terephthalic acid, isophthalic acid and azelaic acid, 0 to 78% by weight; (2) polyether polyurethane resin having a Brookfield viscosity of 100-1200, 0 to 78% by weight; (3) a polyamide as defined, 0 to 94% by weight; and (4) a polyamide as defined, 0 to 97% by weight, the weight percentages based on the total weight of resin in the adhesive composition. The element is particularly useful for the preparation of flexographic printing plates processed in aqueous or semiaqueous basic solutions.