Tuesday, July 30, 2013

Mini Alarm

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. A complementary transistor-pair is wired as a high efficiency oscillator, directly driving a small loudspeaker. Low part-count and 3V battery supply allow a very compact construction.


Parts:

R1 = 330K
R2 = 100R
C1 = 10nF-63V
C2 = 100uF-25V
Q1 = BC547
Q2 = BC327
B1 = 3V Battery or Two AA Cells in Series
SW1 = Read Switch & Small Magnet
SPKR = 8R Loudspeaker (See Notes)


Notes:

* The loudspeaker can be any type; its dimensions are limited only by the box that will enclose it.
* An on-off switch is unnecessary because the stand-by current drawing is less than 20µA.
* Current consumption when the alarm is sounding is about 100mA.
* If the circuit is used as anti-bag-snatching, SW1 can be replaced by a 3.5mm mono Jack socket and the magnet by a 3.5mm. Mono Jack plugs having its internal leads shorted. The Jack plug will be connected to the tiny cord etc.
* Do not supply this circuit at voltages exceeding 4.5V: it will not work and Q2 could be damaged. In any case a 3V supply is the best compromise.

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Monday, July 29, 2013

Alternator Wiring Questionpage450965

Alternator Wiring on 1990 Mercruiser 350 Alternator Wiring Diagram
1990 Mercruiser 350 Alternator Wiring Diagram.


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Magazin Componente Electronice Cluj Anode Half Reaction.


Alternator Wiring on Alternator Wiring
Alternator Wiring.


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68 Charging At 14 8v And Acid Leaking From The Battery Vintage.


Alternator Wiring on Serpentine Alternator Wiring
Serpentine Alternator Wiring.


Alternator Wiring on Please Note The Fuse Wire Connected To The Starter Solenoid And Not
Please Note The Fuse Wire Connected To The Starter Solenoid And Not.


Alternator Wiring on Marine Alternator Diagram Mando Alternator Wire Marine Alternator
Marine Alternator Diagram Mando Alternator Wire Marine Alternator.


Alternator Wiring on Alternator Wiring Question   Page 1   450965
Alternator Wiring Question Page 1 450965.


Alternator Wiring on Alternator Regulator Troubleshooting
Alternator Regulator Troubleshooting.


Alternator Wiring on Alternator Bracket For The Top Mounting About   15 On Line The Wiring
Alternator Bracket For The Top Mounting About 15 On Line The Wiring.


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Wednesday, June 12, 2013

Air Flow Detector circuit Schematic with explanation

This simple circuit uses an incandescent lamp to detect airflow. With the filament exposed to air, a constant current source is used to slightly heat the filament. As it is heated, the resistance increases. As air flows over the filament it cools down, thus lowering its resistance. A comparator is used to detect this difference and light an LED. With a few changes, the circuit can be connected to a meter or ADC to provide an estimation on the amount of air flow. Air Flow Detector circuit Schematic

Parts

Part
Total Qty.
Description
Substitutions
R11100 Ohm 1/4W Resistor
R21470 Ohm 1/4W Resistor
R3110k 1/4W Resistor
R41100K 1/4W Resistor
R511K 1/4W Resistor
C1147uF Electrolytic Capacitor
U1178L05 Voltage Regulator
U21LM339 Op Amp
L11#47 Incandescent lamp with glass removed (See "Notes")
D11LED
MISC1Board, Wire, Sockets for ICs, etc.

Notes

  1. The glass will have to be removed from L1 without breaking the filament. Wrap the glass in masking tape and it in a vise. Slowly crank down until the glass breaks, then remove the bulb and carefully peel back the tape. If the filament has broken, you will need another lamp.
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58 of Americans survey online before shoppping online

Pew Internet and American Life Project has just released the latest the survey results of online shopping habits of Americans . One of it: 58% of Americans said that they have investigated before buying anything online, and this proportion is only 49% in 2004. In these respondents, who call themselves Internet users rose to 78%.

In addition, to investigate not only the proportion of shopping before the increase, and the network of people has also increased the frequency of the investigation.

21% of adults engage in every day of this survey, one in 2004 compared to only 9%.


American research, reviews, online shopping more and more
In addition to the website to read the description of products and services in addition, many people also add a Review of information, analysis, views of the product, especially through social networking sites. 24% of Americans said they would comment after buying things.
The Pew study also online shopping of American spending habits have been studied. There have been online shopping experience of Americans in May 2000 from 36% to 52% now. Meanwhile, online booking air tickets and hotels from 22% to 52%.

The study also found that study habits between men and women of similar, but high-income groups than low-income populations of the network to investigate more. High income and highly educated people post reviews and comments more frequently.

Many Americans are shopping online before comparing the price, quality and product review. Even if the end did not buy the site, but in the store shopping, they will advance the investigation and decision-making on the Internet.
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Mini Guitar Bass Amplifier circuit and explanation

Output power: 6W into 4 Ohm load, FET input stage - Passive Tone Control

Tiny, portable Guitar Amplifiers are useful for practice on the go and in bedroom/living room environment. Usually, they can be battery powered and feature a headphone output. This project is formed by an FET input circuitry, featuring a High/Low sensitivity switch, followed by a passive Tone Control circuit suitable to Guitar or Bass. After the Volume control, a 6W IC power amplifier follows, powered by a 12-14V dc external supply Adaptor or from batteries, and driving a 4 Ohm 10 or 13cm (4"/5") diameter car loudspeaker. Private listening by means of headphones is also possible.

Circuit diagram:Mini Guitar-Bass Amplifier Circuit Diagram
Mini Guitar-Bass Amplifier Circuit Diagram
Parts:

P1______________1M Linear Potentiometer
P2____________100K Log Potentiometer
R1_____________68K 1/4W Resistor
R2____________470K 1/4W Resistor
R3______________2K7 1/4W Resistor
R4______________8K2 1/4W Resistor
R5____________680R 1/4W Resistor
R6____________220K 1/4W Resistor
R7_____________39R 1/4W Resistor
R8______________2R2 1/4W Resistor
R9____________220R 1/4W Resistor
R10_____________1R 1/4W Resistor
R11___________100R 1/2W Resistor
R12_____________1K5 1/4W Resistor
C1____________100pF 63V Polystyrene or Ceramic Capacitor
C2,C5,C9,C14__100nF 63V Polyester Capacitors
C3____________100µF 25V Electrolytic Capacitor
C4_____________47µF 25V Electrolytic Capacitor
C6______________4n7 63V Polyester Capacitor
C7____________470pF 63V Polystyrene or Ceramic Capacitor
C8______________2µ2 25V Electrolytic Capacitor
C10___________470µF 25V Electrolytic Capacitor
C11____________22nF 63V Polyester Capacitor
C12__________2200µF 25V Electrolytic Capacitor
C13__________1000µF 25V Electrolytic Capacitor
D1______________3mm red LED
Q1____________BF245 or 2N3819 General-purpose N-Channel FET
IC1_________TDA2003 10W Car Radio Audio Amplifier IC
SW1,SW2________SPST toggle or slide Switches
J1____________6.3mm Mono Jack socket
J2____________6.3mm Stereo Jack socket (switched)
J3_____________Mini DC Power Socket
SPKR__________4 Ohm Car Loudspeaker 100 or 130mm diameter

Notes:
  • Connect the output Plug of a 12 - 14V dc 500mA Power Supply Adaptor to J3
  • Please note that if the voltage supply will exceed 18V dc the IC will shut down automatically
Technical data:

Output power (1KHz sinewave):
6W RMS into 4 Ohm at 14.4V supply
Sensitivity:
50mV RMS input for full output
Frequency response:
25Hz to 20kHz -3dB with the cursor of P1 in center position
Total harmonic distortion:
0.05 - 4.5W RMS: 0.15% 6W RMS: 10%

Tone Control Frequency Response:
Mini Guitar/Bass Amplifier  circuit
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Electronic Privacy Screen Of Dell Protect Privacy In Public Places

October 2008, Dells provides a new security technologies which is Electronic Privacy Screen for its next-generation Latitude business notebook flagship model E6400. However, there are still few user who understand the function so far. Here I am explain it again today.
Over the past few years, display manufacturers have been increasingly viewing angle will be as a promotional selling point. If you use at home, of course, the higher the better viewing angle, but in the workplace, coffee shop, airport or other public places, privacy and data security issues become more exposed. Members may have noticed that some of my colleagues has focused laptop privacy screen labeled anti-spy film.
Currently, only Dell Latitude E6400 can support electronic security shield technology, Dells official website users can be customized when ordering. This notebook is equipped with software-driven display screen can create a pixel-based pattern, so it can narrow the viewing angle the screen to avoid being shown the privacy of important data or content is sweeping others. This feature is activated, the user only in the notebook before had just being able to clearly see the displayed content, and in the side, the content is completely unable to see.
Electronic Privacy Screen almost have nothing to do with the display brightness, it can be activated just by the shortcut key combination (FN + E) or the Dell ControlPoint software. The consumers who focus on data security and privacy of may try it.
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Wednesday, June 5, 2013

Chevrolet Corvette Electrical Wiring Diagramcircuit Schematic

Block Wiring Diagram on From Here You Will Continue The Run To The 66 Block At
From Here You Will Continue The Run To The 66 Block At.


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Chevrolet Corvette V8 Electrical Wiring Diagram Circuit Schematic.


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Where Can I Get Factory Brake Line Routing For A Justanswer.


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Bosch Esi Tronic 2011 04 7 66 Gb Single Extraction Interchangable No.


Block Wiring Diagram on Here You Can See The Connecting Block Attached To The 110 Block
Here You Can See The Connecting Block Attached To The 110 Block.


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Telephone Block Wiring Smart Reviews On Cool Stuff.


Block Wiring Diagram on Wiring Diagrams Wiring Diagrams 1988 Jeep Cherokee 1988 Wiring
Wiring Diagrams Wiring Diagrams 1988 Jeep Cherokee 1988 Wiring.


Block Wiring Diagram on Ss Real 1966 Chevelle Ss Project 400x300 66 Chevelle Wiring Diagram
Ss Real 1966 Chevelle Ss Project 400x300 66 Chevelle Wiring Diagram.


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Jr Fuel Enrichment Option Wiring Diagram Msd Is The Sebring.


Block Wiring Diagram on 66external Wiring Diagram Jpg
66external Wiring Diagram Jpg.


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