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Introduction of wireless mobile speed warning

2016-02-18 05:32  
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Here is the speed alarm wireless mobile  unit  briefly. The speed alarm wireless mobile unit to adapt to most internal combustion engine vehicles. There is a strict relationship betw1een engine speed and vehicle speed, so control the speed of the device and start beeping and flashing a leader once per second, when the speed reaches the maximum fixed. Its distinctive feature is that the circuit need not be connected to the engine. This circuit is designed to alert the driver that he has reached the maximum fixed speed limit (ie, at a highway). It eliminates the necessity of looking at tachometer and distracted driving. Figure: IC1 form a differential amplifier electromagnetic pulses generated by the engine spark plugs, recipients through the sensor coil L1. IC2A further amplified pulses and IC2B to IC2F pulse square wave inverter provides clean. The monostable multivibrator IC3A as frequency discriminator, its pin 6 must resolutely high when the speed limit (settled by the R11) was achieved. IC3B, transistors and vice component provides timing signal part by LED D5 and piezo BZ1 sound. D3 introduces a small amount of hysteresis. In this schematic: D1 is necessary to transmit the spark plug in the monitor settings, so you can easily find the best position of the device on the dashboard or close to it. After setting completed, D1 & R9 can be ignored or turned off, the battery savings. In the previous operation must be adjusted R8 better results. The best setting is usually fine when it is obtained where the value betw1een 10 and 20 k.
You must do this in the first set but in the vehicle when the engine is stopped. Finally a simple setting can help a
The second person. Driving the vehicle, reaching speeds needed. This helper must adjust the trimmer R11 until the device is operating pagers and D5. Reduce the speed of the car must be stopped at the beep. L1 can be a 10 mh small inductor usually sold in the form of small rectangular plastic box. If you need a higher sensitivity you can build a special coil, the coil 130-150 rpm 0.2 mm. Enameled in 5 cm. Diameter before (if we can). Extraction coil former and tape with insulation tape manufacturers therefore a separate coils. Circuit current map is approximate. 10 horses. If you intend to use the car's 12 v battery, you can connect the device to the cigarette lighter socket. In this case, R20 to 330 r. Number of cylinders of the engine, can not. R11 The device settings are correct. In some cases, you must use the R11 = 200 k and 100 k or less R12 =. If you need to install the device, a variable sine or square wave generator is required. Calculating the frequency and speed in four-stroke engines can use the following formula: Hz = (Number of cylinders * RPM) / 120. For a tw1o stroke engine formula is: Hz = (Number of cylinders * RPM) / 60. Thus, for a four-cylinder with four-stroke engines and the resulting frequency @ 3000 rpm 100 Hz. Temporarily disconnect C2 from IC1 pin 6. C2 connected to the generator output and ground. Set the generator frequency is 100 Hz. And norms until you hear a beep and leadership D5 R11 flash. Reduced to 99 or 98 hertz, beep, flash must be stopped. This circuit is not suitable for diesel engines.

SpeedAl speed alert wireless portable unit


R1,R2,R19_______1K 1/4W Resistors

R3-R6,R13,R17_100K 1/4W Resistors

R7,R15__________1M 1/4W Resistors

R8_____________50K 1/2W Trimmer Cermet

R9____________470R 1/4W Resistor

R10___________470K 1/4W Resistor

R11___________100K 1/2W Trimmer Cermet (see notes)

R12___________220K 1/4W Resistor (see notes)

R14,R16________68K 1/4W Resistors

R18____________22K 1/4W Resistor

R20___________150R 1/4W Resistor (see notes)

C1,C7_________100?F 25V Electrolytic Capacitors

C2,C3_________330nF 63V Polyester Capacitors

C4-C6___________4?7 25V Electrolytic Capacitors

D1,D5______Red LEDs 3 or 5mm.

D2,D3________1N4148 75V 150mA Diodes

D4________BZX79C7V5 7.5V 500mW Zener Diode

IC1__________CA3140 or TL061 Op-amp IC

IC2____________4069 Hex Inverter IC

IC3____________4098 or 4528 Dual Monostable Multivibrator IC

Q1,Q2_________BC238 25V 100mA NPN Transistors

L1_____________10mH miniature Inductor (see notes)

BZ1___________Piezo sounder (incorporating 3KHz oscillator)

SW1____________SPST Slider Switch

B1_______________9V PP3 Battery (see notes)