AFX Slot Car Lap Counter

AFX slot car sets are very enjoyable but you can increase the fun with a lap counter. This circuit will count from 00 to 99, with independent counters for each track. The sensing device used is a Hall effect sensor (UGN3503; available from Dick Smith Electronics). One of these sensors is glued under a section of each track (printed side up); between the slot and one of the track rails is the best spot. In this position, it will allow the ground effects magnets on the cars to pass over them. The sensor will provide a voltage of about 3V when a car passes over it and about 2V without a magnetic field. Both counter circuits are identical, with dual op amp IC5 handling the signals from both sensors.

Circuit diagram:

 AFX Slot Car Lap Counter Circuit diagram

IC5a and IC5b are wired as comparators, with a 2.5V reference derived from zener diode ZD1 via the 10kO and 12kO resistors. Each time the output of IC5a goes high it clocks IC1a, a 4518 BCD counter. NAND gates IC2a & IC2b provide a carry out to the other half of IC1 for a 2-digit display. More counters may be cascaded this way to provide extra digits. The BCD outputs of IC1 drive 7-segment decoders IC3 & IC4 which drive common cathode LED displays. Push-button S1 resets the counters to 00 for both tracks for the start of a new race.

Author: Placid Talia - Copyright: Silicon Chip Electronics

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High Power Car Battary Eliminator

To operate car audio (or video) system from household 230V AC mains supply, you need a DC adaptor. DC adaptors available in the market are generally costly and supply an unregulated DC. To overcome these problems, an economical and reliable circuit of a high-power, regulated DC adaptor using reasonably low number of components is presented here.  Transformer X1 steps down 230V AC mains supply to around 30V AC, which is then rectified by a bridge rectifier comprising 5406 rectifier diodes D1 through D4. The rectified pulsating DC is smoothed by two 4700μF filter capacitors C1 and C2. The next part of the circuit is a seriestransistor regulator circuit realised using high-power transistor 2N3773 (T1). 

 

Fixed-base reference for the transistor is taken from the output pin of 3-pin regulator IC1 (LM 7806). The normal output of IC1 is raised to about 13.8 volts by suitably biasing its common terminal by components ZD1 and LED1. This simple arrangement provides good, stable voltcuit age reference at a low cost. LED1 also works as an output indicator.Finally, a crowbar-type protection circuit is added. If the output voltage exceeds 15V due to some reason such as component failure, the SCR fires because of the breakdown of zener ZD2. Once SCR fires, it presents a short-circuit across the unregulated DC supply, resulting in the blowing of fuse F1 instantly. This offers guaranteed protection to the equipment connected and to the circuit itself.

 

This circuit can be assembled using a small general-purpose PCB. A goodquality heat-sink is required for transistor T1. Enclose the complete circuit in a readymade big adaptor cabinet as shown in the figure.

Streampowers

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USB Car Charger Adapter

This USB car charger adapter project is a DC DC power converter that safely converts the 12V car battery voltage into stable 5V. This USB car charger circuit can be used to supply power from a car cigar lighter socket to a portable device that require a 5 volts . This circuit makes it possible to power/recharge any USB power-operated device, using in-dash board cigar lighter socket of your car.

USB Car Charger Adapter Circuit diagram

The DC supply available from the cigar lighter socket is fed to an adjustable, three-pin regulator LM317L (IC1). R1 and R2 resistors regulate the output of IC1 to steady 5V, which is available at the ‘A’ type female USB socket. Red LED1 indicates the output status and zener diode ZD1 acts as a protector against high voltage.As you can see in the circuit diagram , the circuit is very simple and require just few common cheap components .Because this circuit not require many components , you can put all components in the cigar plug socket .

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100W Quad Car Amplifier circuits

This quad final amplifier is actually intended to be used in a car, but it can naturally also be used for a variety of other medium-power applications. The TDA7375A can be successfully used in all situations in which a reasonable amount of audio power is desired and only a relatively low supply voltage is available. This IC is the successor to the TDA7374B, which forms the heart of the active loudspeaker system described earlier this year. Such a quad IC amplifier is naturally an excellent choice for this application, especially since the individual amplifiers can be connected in pairs in the bridge configuration, which allows them to provide approximately four times as much power.

 In addition, all inputs have RC networks (R1/C1, etc.) to block possible RF interference. The function of R6 is to separate the grounds of the input and output stages, in order to avoid possible ground loops that might arise with the use of multiple modules. A 5-W type is used for this resistor, in order to prevent it from going up in smoke if the ground connection of the power supply comes loose. C10 decouples the internal voltage divider, which biases the internal amplifier stages to half of the supply voltage. RC network R5/C9 provides a delayed, plop-free switch-on.

 C15 and C16 are local bypass capacitors for the supply voltage. The power supply ripple rejection of the TDA7375A is approximately 50 dB. If you want to use only a transformer, bridge rectifier and smoothing capacitor for the power supply, the minimum requirement is a transformer rated at 12 V / 30 VA in combination with a 10,000-µF electrolytic capacitor (remember that the maximum allowable supply voltage is 18 V). One of the few drawbacks of this quad amplifier is that two of the channels are inverted with respect to the other two. For this reason, the polarity of each loudspeaker terminal is marked on the circuit board layout (e.g., +LS1 and –LS4) to indicate which terminal of the loudspeaker should be connected where.


Radial electrolytic capacitors rated at 3300µF/16V and having a diameter of only 12 mm are used for the output capacitors, which allows the circuit board to remain relatively compact. Our preferred type of electrolytic capacitor is a member of the Rubycon ZL series, which can handle no less than 3.4 A of ripple current. The maximum current consumption of the circuit with all four channels driven to the clipping level (with 4-Ω loads) is approximately 2.1 A. The TDA7375A can also be used with 2-Ω loads. However, in this case the internal temperature rises considerably, since the Multiwatt 15V package has a rather large thermal impedance of 1.8 ºC/W.
In the interest of the service life of the IC, it is thus a good idea to use a somewhat larger heat sink. A 4 A/T fuse has been selected in consideration of possible 2-Ω operation. If you limit the load to 4 Ω, the fuse value can be reduced to 2 A/T. The output terminals of the amplifiers can be found on the circuit board next to the associated electrolytic capacitors. The related ground connections for LS1 and LS2 are located next to the LS1 and LS2 terminals, but the ground connections for LS3 and LS4 are located on the left, next to the IC, since this gives the best current paths on the circuit board and the least distortion. Vertical car connectors (spade terminals) are used for the power supply connections.
Resistors:
R1-R4 = 100Ω
R5 = 10kΩ
R6 = 0Ω1, 5W
P1-P4 = 10 k preset
Capacitors:
C1,C3,C5,C7 = 15nF
C2,C4,C6,C8 = 220nF
C9 = 10µF 63V radial
C10 = 47µF 25V radial
C11-C14 = 3300µF 16V
C15 = 100nF
C16 = 1000µF 25V radial, max. diameter 13mm
Semiconductors:
IC1 = TDA7375A (ST)
Miscellaneous:
F1 = fuse, 4A/T (time lag), with PCB mount holder 2 fast-on (spade) terminal, male, vertical, solder type (2-pin version)
Measurement results
Supply voltage = 14.4 V
Quiescent current = 100 mA
Pmax. (0.1% THD) = 4 × 5.3 W/ 4Ω
Input sensitivity = (5.2 W/4 Ω) 0.5 V
THD+N (B = 80 kHz, 1 kHz 1W/4 Ω) = < 0.04 % Bandwidth = 28 Hz to 55 kHz

100W Quad Car Amplifier circuits.

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The Pursuit of Superior Taste With Th Cool Car Electronic Accessories

BMW Car - Base iPad

Buying a iPad is a very simple for vehicle owners, but where to put the iPad is a problem. Recently, the luxury brand BMW has released the base of ipad in the car first, it can combine seamlessly with Apples products, including text messages, memos, E-mail and so on.
BMW said that in 2011 all its new products, these will be the standard base with the sale, BMW will be the first comprehensive introduction of Apples automotive OEM manufacturers.
Rolls-Royce portfolio picnic tableware
With the car, the radius of human activity is expanding, and weekend outdoor activities Hupenghuanyou is many peoples regular operations. So, if you have an appropriate combination of picnic utensils, driving some to be the most wonderful time. Recently, Rolls-Royce for the Phantom (quotations picture parameters
Number) with introduction of a special combination of select --- 4 picnic. This set of 4 aluminum alloy used in combination with a picnic, wood, leather and other materials, containers are also sterling silver, crystal and other material, there is no published price, but can be worth the price of a domestic car is for certain. It is reported that
A limited edition of 100 sets of cutlery set will be issued.

Ferrari - H4D Camera
Travel driving, how the line without a camera? Ferrari also buy a camera or tighten their belts it. Recently, Ferrari Hasselblad camera company co Sweden introduced a very luxurious product --- the red Ferrari H4D digital camera. The aircraft is equipped with a
Support 80mm lens and a 50 million pixel digital back, with the Ferrari factory rossofuoco body paint, the most seductive eyes and ears have to be rocket logo, highlighting the elegant look. Current aircraft specifications and price were not disclosed, is said to direct inquiries to the Ferrari, not
Price certainly had a lot of money, the world is only limited sale 499 units.

Lamborghini - Super Performance "Notebook"
With moving car, and the car owner move ultimately the office at any time, it is necessary to have a super-performance notebook for yourself. Recently, as son of the Lamborghini car company founder Ferruccio Lamborghini, Tonino Lamborghini push out of a latest Lamborghini Slim Notebook. This notebook is equipped with Intel Ultra Low Voltage processor, and it is up to 500GB hard drive configuration with wireless LAN and Bluetooth, 13.4-inch LED screen with a resolution of 1366 × 768, Windows7 system pre-installed, configured 4-cell lithium-ion battery. At the same time with VGA, HDMI, USB, headset microphone, multi-card reader and other interfaces to meet the daily needs, the weight of 1.3 kg.

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