摘要:
Multistage RF transmitter and receiver circuits may use independently variable RF and IF local oscillators, allowing the RF and IF local oscillator frequencies for a given RF channel to be selected to have a large common factor with respect to the reference oscillator used by the local oscillator circuits, thus allowing the use of small divisor numbers in the local oscillator circuits and reducing phase noise. Independent high-side and low-side RF local oscillators may be provided and selectively used depending on the RF channel to be transmitted or received.
摘要:
A speaker box mounting structure includes a holder base having a mounting plate for fastening to a wall or ceiling, a swivel arm set coupled to the holder base and adjustable relative to the holder base to a desired direction and angle, a coupling unit coupled to the swivel arm set, the coupling unit having a base, a coupling portion disposed at the base, and two stop faces disposed at two sides of the coupling portion and defining a contained angle, and a speaker box having a coupling portion coupled to the coupling portion of the coupling unit, and two stop faces disposed at two sides and respectively stopped against the stop faces of the coupling unit.
摘要:
First, second, third, and fourth resistors are coupled to first, second, third, and fourth capacitors. A first positive in-phase terminal is coupled to the first resistor and the first capacitor. A first negative in-phase terminal is coupled to the fourth resistor and the fourth capacitor. A positive quadrature-phase terminal is coupled to the second resistor and the first capacitor. A second positive in-phase terminal is coupled to the first resistor and the second capacitor. A second negative in-phase terminal is coupled to the fourth resistor and the third capacitor. A negative quadrature-phase terminal is coupled to the third resistor and the fourth capacitor. The first and fourth resistors, the second and third resistors, the first and fourth capacitors, and the second and third capacitors are equal distances from and on a same side of respective axes, and are equal distances from and on opposite sides of a symmetry axis.
摘要:
A speaker stacking structure includes a speaker, the speaker having two bearing walls at two sides of the speaker cabinet thereof, a plurality of locating blocks respectively symmetrically fastened to the bearing walls of the speaker, each locating block having a plughole, and a plurality of fastening members insertable into the plugholes of the locating blocks to join two speakers in a stack.
摘要:
Multistage RF transmitter and receiver circuits may use independently variable RF and IF local oscillators, allowing the RF and IF local oscillator frequencies for a given RF channel to be selected to have a large common factor with respect to the reference oscillator used by the local oscillator circuits, thus allowing the use of small divisor numbers in the local oscillator circuits and reducing phase noise. Independent high-side and low-side RF local oscillators may be provided and selectively used depending on the RF channel to be transmitted or received.
摘要:
A signal is applied to the body of a MOSFET to enhance the transconductance of the MOSFET. The signal applied to the body of the MOSFET has essentially the same waveform as an input signal supplied to the gate of the MOSFET, and is shifted by approximately 180 degrees with respect to the input signal. The signal applied to the body of the MOSFET may be provided by a phase-adjusting feedback circuit that generates the signal from a signal representing the output of the MOSFET.
摘要:
A modular headboard for a bedstead includes an upper headboard section and a lower headboard section selectively coupled together for convenient storage and transportation. The upper headboard section includes laterally-spaced, vertically-extending upper post sections and a headboard panel extending therebetween. The lower headboard section includes corresponding lower post sections, with cross rails extending between the lower post sections. A laterally-extending slat overlaps adjacent edges of the upper and lower headboard sections to facilitate alignment of the upper and lower headboard sections, and is secured to the headboard sections to form a stable headboard.
摘要:
An audio mixer includes a console, which has a base with an indication face, and different sizes of mounting holes and knob holes, a sound signal processing unit mounted inside the console, a sound signal input zone, which defines multiple sound signal input blocks and has connectors respectively mounted in the sound signal input blocks corresponding to the mounting holes of the console, a sub-control zone, which divides multiple sub-control blocks and has sub-control knobs respectively mounted in the sub-control blocks and the knob holes of the console and electrically connected to the sound signal processing unit, and a main control zone, which defines a main control block, and has an indication provided in the main control block and a main control knob greater in size than the sub-control knobs and electrically connected to the sound signal processing unit and disposed above the indication face of the console.