The 200mW 800m green laser pointer with lock

Visible analog multiplier is the best mixing devices, the design of analog multiplier MC1496 mixer circuit. 3.6.1 The analog multiplier MC1496 introduced according to the double differential made of monolithic integration of analog simulation by multiplying the basic principles of multiplying MC1496 is a four-quadrant multiplier. Shown in Figure 3.16, MC1496 consists of three difference on the tube, the output collector connected to together to balance the multiplier input voltage, so the output signal is the input signal is the product of often several times, including V7, 41 Shandong University of Science and Technology bachelor's degree thesis phase-shift laser rangefinder receiver circuit design of R1, V8, R2, V9, R3, and R5 are composed of multiple current source circuit. The desk charger of  green laser pointer  is very durable.
V7, R5, R1 is the current source reference circuit, V8, V9, respectively, supply the V5, V6 tube constant current I0 / 2, R5 is an external resistor can be used to regulate the size of I0 is / 2, the other two, V5, V6 the emitter leads to terminals 2 and 3, an external resistor RY RY's negative feedback, in order to expand the dynamic range of input voltage U2, RC external load resistance. 8,10-side for the X input, 4,1 end of the Y input, 12,6-side output, 5 termination resistor to adjust the size of the constant current power supply terminal 14 side. Known by the mathematical analysis of linear DC analog multiplier: the scope of the output signal contains only the input signal frequency and difference of two parts. The desk charger of  green laser pointer  is good and durable in quality.
Therefore, the MC1496 can be used in the modulator, mixer, multiplier, multiplier, and other needs similar to the signal characteristics of the signal output of occasions. Low magnification differential amplifier emitter connected to the pins of the chip, so that the external emitter resistance. Similarly, the output at the chip also requires an external load resistance. 3.6.2 mixer circuit analysis mixer circuit analysis of the double differential pair MC1496 Analog Multiplier for the mixer circuit, the main advantage is the mixer gain, the output signal spectrum of pure, mixing interference, the local oscillator voltage transformer the size of the strict limits, and high isolation between ports [17]. And because of the multiplier output voltage does not contain the signal frequency components, thereby reducing the filtering requirements. It is to charge the battery of green laser pointer .
The substance of the mixer for multiplication of two input signals, to extract the difference frequency signal to achieve mixing. 3.14 as follows: the design needs to be 15KHz difference frequency signal, you need to design oscillation frequency of the RLC resonant circuit to 15KHz were two of the input signal difference frequency signal. The mixer circuit design, see Appendix III. RLC resonant circuit design RLC resonant circuit is only one loop of the oscillation circuit is called a simple oscillator circuit inductors and capacitors in series or parallel line into the loop, or the single-oscillator circuit. In a particular frequency, the impedance of a simple oscillator circuit has a maximum or minimum feature called the resonance characteristics of this particular frequency called resonant frequency. It is the desk charger of  green laser pointer .
Simple oscillator circuit has a resonance characteristics and frequency selection, which is the design choices it's important reason to set the resonant frequency of 15KHz, you can obtain the difference frequency signal of the two input signals. Simple resonant circuit including the series resonant circuit with parallel resonant circuit, a series resonant circuit for low-power resistance or low impedance circuit, when the frequency is not very high, the most widely used parallel resonant circuit. The design of 15KHz is not very high frequencies, so choose a parallel resonant circuit. The resonant frequency is f0 = 15KHz, retrieve Road capacitance value of C72 = 0.01uF, then the loop coil inductance value: L1 = 1 w0, C = 11.2mH, 2 loop resonant resistance: R86 = Qw0, L = 1K. The desk charger of  green laser is black color.