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How a nuclear reactor works

How to Make a LED Circuit with Timer 555

This circuit LED reproduces the first LED sequence at this time used by FISA on behalf of Formula single racing. It may perhaps be alive used with slot car sets (such for example HO shin up AFX/Life Like/Tyco sets) or else means of communication controlled cars. IC1, a 555 timer IC, is used as a watch pulse generator. Its output is fed via NAND gates IC2a and IC2c to IC3, a 4024 binary counter. IC2b inverts the O4 output of 4024 binary counter IC3. originally, IC3 is reset and all its outputs are low, together with O4, which causes IC2b to present-day a rational climax to the pin 8 input of IC2c which after that passes pulses from the 555 timer circuit to the clock input of the 4024. IC3 then begins together with. LED Circuit with Timer 555 Circuit Diagram Following the count has reached binary 1111, the subsequently pulse sends the O4 output of IC3 high, which disables IC2c and IC3 stops with. The four used outputs of IC3 are connected to a resistor ‘ladder’ which acts to the same deg...

How to build Solar Cell Voltage Regulator

Description This device is designed to be a simple, inexpensive ‘comparator’, intended for use in a solar cell power supply setup where a quick ‘too low’ or ‘just right’ voltage indicator is needed. The circuit consists only of one 5V regulator, two transistors, two LEDs, five resistors, two capacitors, and one small battery. Although a 4-V battery is indicated, 4.5 V (3 alkalines in series) or 3.6 V (3 NiCd cells in series) will also work. The specifications of voltage regulator IC1 are mainly determined by the size and number of the solar cells and the current pull of the equipment connected to the output. Here the low-drop 4805 is suggested but other regulators may work equally well as long as you observe the output voltage of the solar cells. Transistors T1 and T2 are complementary types i.e. one each of the pnp and npn variety. Circuit diagram: Although the ubiquitous BC557B (pnp) and BC547B (npn) are indicated, any small-signal equivalents out of the junk box will probably do....

How to Build Unregulated Linear Power Supply

Unregulated power supplies contain four basic components: transformer, rectifier, filter capacitor, and a bleeder resistor. This type of power supply, because of Us simpticity, is the least costly and most reliable for low power requirements. The disadvantage is that the output voltage is not constant It will vary with the input voltage and the load current, and the ripple is not suitable for electronic applications. The ripple can be reduced by changing the filter capacitor to an LC (inductor-capacitor) filter but the cost to make this change would make use of the regulated linear power supply a more economical choice.

How to make an Apple II computer fit on your wrist streampowers

About a year ago I came across an interesting article in Make Magazine about a guy who took his Fossil Wrist PDA and installed an Apple II emulator on it.   He was able to load many of the Apple II software titles and run them at regular speed.   The thought of having a fully functioning Apple computer on my wrist excited me enough to give it a try.      People that are attempting to do this should be familiar with the Palm OS as well as using jot or Graffiti 2 as an input method.   The Fossil Wrist PDA (now discontinued) features a tiny gray 160×160 pixel screen, the same number of pixels as most palm devices up to Palm III, with 16 shades of gray. The watch runs Palm OS 4.1 with its 66MHz processor and has a tiny stylus hidden in the watch clasp. It is able to carry out most PDA functions, and run any normal Palm OS-compatible application (up to 4.1). It features 8 Mb of RAM (about 7.7 Mb available to user) and 4 Mb of flash memory. Like other Palm OS de...

How to build Personal alarm

Small, portable, anti-bag-snatching unit Also suitable for doors and windows control Circuit diagram Parts: R1 330K 1/4W Resistor R2 100R 1/4W Resistor C1 10nF 63V Polyester or Ceramic Capacitor C2 100µF 25V Electrolytic Capacitor Q1 BC547 45V 100mA NPN Transistor Q2 BC327 45V 800mA PNP Transistor SW1 Reed Switch and small magnet (See Notes) SPKR 8 Ohm Loudspeaker (See Notes) B1 3V Battery (two A or AA cells wired in series etc.) Device purpose: This circuit, enclosed in a small plastic box, can be placed into a bag or handbag. A small magnet is placed close to the reed switch and connected to the hand or the clothes of the person carrying the bag by means of a tiny cord. If the bag is snatched abruptly, the magnet looses its contact with the reed switch, SW1 opens, the circuit starts oscillating and the loudspeaker emits a loud alarm sound. The device can be reverse connected, i.e. the box can be placed in a pocket and the cord connected to the bag. This device can be very useful in s...

HOW TO USE KEIL

Finally you have decided to write your own code for the 8051 microcontroller. It doesn't matter whether you have chosen Assembly or C Language for yourself but what matters now is that you need an environment specially designed for 8051. Basically you are looking out for IDE (Integrated Development Environment) that will help you build and compile programs. While there are many options out there, I prefer KEIL uVision in this regard. UPDATE: You can also click this link for an updated version of this post. READ MORE

How to build Speaker Microphone Circuit

Description: This circuit takes an ordinary loudspeaker and allows it to be used in reverse, as a microphone. Circuit diagram Notes: This circuits allows you to use a cheap loudspeaker as a microphone.Sound waves reaching the speaker cone cause fluctuations in the voice coil. The voice coil moving in the speakers magnetic field will produce a small electrical signal . The circuit is designed to be used with an operating voltage between 6 and 12 volts dc. The first transistor operates in common base mode. This has the advantage of matching the low input impedance of the speaker to the common base stage, and secondly has a high voltage gain. The second stage is direct coupled and operates in emitter follower. Voltage gain is slightly less than unity, but output impedance is low, and will drive long cables. Speech quality is not as good compared to an ordinary or ECM microphone, but quite acceptable results can be obtained. Speaker cones with diameters of 1 inch to 3 inches may be used....

How to build 1 5V to 5V 12V DC DC Converter with LT1073

Small 1.5V to 5V or 12V DC/DC converter with LT1073 chip. The IC is available in three different versions, depending on output voltage. Two with fixed output voltage of 5V and 12V, and the most interesting that can be adjusted. The adjustment is done through a voltage divider with two resistors, of mass, output and Terminal 8, internally connected to the voltage comparator IC, which is responsible for stabilizing the output voltage. LT1073 has an internal everything you need to make a small DC / DC converter with a low operating voltage of only 95μA 1V and consumption without load. If you do not have a meter inductance, the inductive part of the drive is a bit more complicated to make, but we shall see some possible solutions. Capacitor also recommended by the manufacturer for the circuit is a bit hard to get, I have used a tantalum recovered from another power source, and the ripple voltage at the output is quite low. Last but not least, say that the diode has to be a fast, not wo...

Changhong PF29GA18A – How to enter service mode – circuit diagram – 29 inch color TV

ETA-1D chassis is applied in PF29GA18A series. By use of Toshiba V/C/D-MCU 2IN1 IC for TV small signal processing and bus control, the chassis enables TV tuning, adjustment, control and picture correction, featuring high-integration, high-performance-to-price ratio and high-reliability and compact circuit with fewer external components. The chassis, widely used in small and medium TVs, provides much more convenience for manufacturing and technical service. It includes: 2IN1 IC 8897PSBNG-4VB6 for PAL/NTSC small signal processing and bus control [TMPA8897CMANG /CPANG/CRANG /CSANG] EEPROM AT24C16 for data memory LA78041 for vertical output power amplifying LA42102 for audio power amplifying TA1343N for audio processor FSCQ1265RTYDTU for power circuit adjustment and control. BSC68DG (FBT) Mask ROM: TMPA8897CPBNG (ROM size: 48k) Mask ROM: TMPA8897CRBNG (ROM size: 56k) Mask ROM: TMPA8897CSBNG (ROM size: 64k) OTP ROM: TMPA8897PSBNG (ROM size: 64k) Color systems: PAL, NTSC Sound systems: D/K B...