what is a capacitor and How to Replace Capacitor

what is a capacitor and How to Replace Capacitor

This is capacitor replacement tutorial video. This video describes how to replace the damage capacitor with new capacitor. The capacitor has two important reading, they are capacitance and voltage. The capacitance shows how much energy that can hold that given voltage. The voltage reading shows the maximum voltage that capacitor can handle before it exploded. To replace the damage capacitor, we must replace it with capacitors that has the same capacitance and the same or higher voltage.

100W Audio Amplifier Transistor used BDW83D - BDW84D circuit diagram

100W Audio Amplifier Transistor used BDW83D - BDW84D circuit diagram         

Here 100 watt power audio amplifier which using power transistor BDW83D and BDW84D. Copyright belong to Smart Kit.

Schematic diagram:

Component part list:

R1 = 1,2 K                                   D1 = 1N4002-7  

R2 = 0,47 OHM                           D2 = 1N2002-7  

R3 = 220 OHM                            D3 =  1N4148     

R4 = 3,9 K                                   D4 = 1N4148      

R5 = 2,2 K                                   D5 = 1N4148      

R6 = 2,2 K                                    D7 = 1N4148     

R7 = 10 K                                    D8 = 1N4148      

R8  = 4,7 K                                  Q1 = BDW84D   

R9 = 150 OHM                            Q2 = BD829       

R10 = 39 OHM                            Q3 = BC546       

R11 = 3,3 K                                  Q4 = BC556      

                                 

20 WATT FLUORO INVERTER used tip3055

20 WATT FLUORO INVERTER used tip3055

This circuit will drive a 40 watt fluoro or two 20watt tubes in series.
The transformer is wound on a ferrite rod 10mm dia and 8cm long.

The wire diameters are not critical but our prototype used 0.61mm wire for the primary and 0.28mm wire for the secondary and feedback winding.
Do not remove the tube when the circuit is operating as the spikes produced by the transformer will damage the transistor.
The circuit will take approx 1.5amp on 12v, making it more efficient than running the tubes from the mains. A normal fluoro takes 20 watts for the tube and about 15 watts for the ballast.
source : http://talkingelectronics.com/projects/200TrCcts/200TrCcts.html

SAMSUNG LE32A430 user guide

Precautions When Displaying a Still Image
A still image may cause permanent damage to the TV screen.
•   Do not display a still image on the LCD panel for more than 2 hours as it can cause screen
image retention.
This image retention is also known as "screen burn".  
To avoid such image retention, reduce the degree of brightness and contrast of the screen
displaying a still image.
•      Watching the LCD TV in 4:3 format for a long period of time may leave traces of
borders displayed on the left, right and center of the screen caused by the differen
of light emission on the screen. Playing a DVD or a game console may cause a si
effect to the screen. Damages caused by the above effect are not covered by the Warranty.
•   Displaying still images from Video games and PC for longer than a certain period of time m
produce partial after-images.
To prevent this effect, reduce the ‘brightness’ and ‘contrast’ when displaying still images.

download SAMSUNG LE32A430 user guide
key word :

samsung le32a430 samsung le 32a430

SAMSUNG LE32A430 user guide

Testing a Triac

Testing a Triac

These two testing procedures are for use with a digital multimeter in the Ohm's test-range. Testing procedure was actually designed for testing inside micro-waves (magnetrons), but should be no difference in any other circuit. Test in- or out circuit.

A Triac is an electronic switch or relay. Triacs come in many shapes, sizes, and colors. Check the standard terminal designations in the picture below which shows most of the types of triacs that are commonly used in microwave ovens, along with their standard terminal designations.

Located either externally or fixed within an appliance or equipment, the triac operates when it receives an electronics "gate" signal from the control circuitry. It then switches to its closed or "on" state, thus providing for example, a voltage path to the primary winding of the H.V. transformer in a microwave oven and so activating the cooking controls. Or used in a laboratory water-bath which needs to be kept on a specific temperature. The probe-sensor, which is immersed in the water, keeps track of the temperature and sends a gate signal to the triac to either switch on the heating or cooling elements. Most of these probe sensors only contain one or more diodes of the general 1N4148 or 1N914 types.

more info

source : http://www.sentex.ca/~mec1995/gadgets/triactst.htm