Electronics Engineering

The purpose of the diode is to prevent electricity to flow in the wrong direction in a circuit. The purpose of the diode is to prevent electricity to flow in the wrong direction in a circuit.

haha...i also asking this question..u r who

These are the crests and troughs of the wave (in a ripple on the surface of water or other liquid).

Incandescent light cannot be used for a fiber optic transmitter. This is because incandescent light is too slow for such a transmitter.

no... frequency refers to the number of times something happens in a given amount of time, ie: hertz is full waves passing a point in a second.

however, since waves are additive, you can produce an "anti-wave" that in-effect cancels out a wave

Satellite broadcasters such as direct tv and dish network have all ways transmitted digital from day one.

lodestone is a form of magnetite which has strong magnetic qualities. These qualities led to the use in early compasses.

Also known as basic insulation level (BIL): A specific insulation level, expressed in kilovolts, in accordance with which the complete system (including the line pole insulation to earth at every pole, the switchgear, the line isolators and reclosers, and the substations connected to the system, including their transformers) is designed and constructed. (NRS 039:1995)

A diode is a component that lets current flow in only one direction. A zener diode has an additional property that current will begin to flow in the reverse direction when a reverse voltage is applied above a certain threshold. This property is generally used for voltage regulation purposes. A diac has similar voltage regulating properties but behaves the same in both directions - current will flow through it when a voltage above it's threshold voltage is applied in either direction. It is therefore useful in AC as well as DC circuits. Below the threshold voltage the diac will be off - no current will flow. A diac is electrically similar to a neon bulb or gas regulator tube.

There are many different advantages of a microprocessor based system. Some of these include that it only uses 3 components so it is simple to use and install and it will increase your memory.

This is the European "Pro-electron" numbering system compared with the US JEDEC system (2N etc)

First - Letter

A = Germanium Device
B = Silicon Device
C = Gallium Arsenide

Second - Letter for A/B/C devices

A = small signal diode
C = small signal general purpose transistor (for audio or slow speed switching)
D = power transistor (audio and low frequency applications_
F = small signal RF transistor
T = SCR / Thyristor
U = power transistor for switching applications
Y = rectifier diode

Third + Fourth + Fifth - Unique identifier number

Some manufacturers put some significance on the number. For example Mullard/Philips treated the second digit of 4 meaning NPN Lockfit case and 5 meaning PNP lockfit. Many used 6 for TO92 cases.

An optional letter followed indicating a gain grouping ... typically A being lowest, B middle and C highest

Different manufacturers created similar transistors with different type markings.

e.g. BC107 BC167 all functionally very similar.

So, the BC147 is a Silicon small signal audio transistor with a "Lockfit case" originally manufactured by/for Philips/Mullard. A viable replacement today, if you can't find a 147 is a BC547 If there's a gain grouping letter, you need to match the gain grouping either by a comparable letter, or by testing. Careful with the pinout.

There are a cluster of similar transistors ...

So, the BC147 is one of a cluster of 3 similar transistors ... BC147/148/149. BC147 has ratings of VCE 50, VCB 45 ICMAX 100 hfe 125-500
BC148 has ratings of VCE 30, VCB 20 ICMAX 100 hfe 125-500
BC149 has ratings of VCE 30, VCB 20 ICMax 100 hfe 240-900 Noise 2dB

Lockfit transistor pinout (wideface down)
B
E C

BC547 pinout (flatface down)

E B C

The bit addressable memory in 8051 is compose from 210 bits:

- bit address space: 20H - 2FH bytes RAM = 00H - 7FH bits address;

- SFR registers;

The following addresses are NOT bit addressable, only 1-byte addressable:

- 32 bytes RAM from 00H to 1FH (R0 - R7 registers in all four banks);

- 80 bytes RAM general user from 30H to 7FH.

They are pheromones.

landline phones can only be used near their holder, or in the house or place they are connected to, but mobile phones can be used almost anywhere providing you have enough credit (money to use on phone) to make calls and send texts. only mobile phones can send texts and images. mobile phones also need to be charged regularly to keep the battery power filled up. when the battery power runs out, the phone instantly turns itself off. there is a gauge in the corner of the screen that tels you how mucch battery power is left. the more bars of power, the better.

Antifreeze smelling white smoke or fog coming from the vents means you have a leak in the heater core or one of the connections to it. This will only get worse and needs to be repaired before you loose all your coolant. If it smells like burning leaves or grass then it is possible that leaves have found their way into the heater box. A lot of vehicles use a resistor block that is mounted in the heater box to provide resistance for the various blower speeds. When the blower fan is on low speed - then one of these resistors is in series with the blower. The resistor will become quite hot ( normal ) and since it is mounted in the heater box, the air flow will cool it. However if leaves or other foriegn material has found its way into the heater box - these can burn if they come in contact with the resistors. Usually it will happen once and the problem goes away. If it smells like plastic burning - then you may have a wiring issue.

A sound wave.

49 MHz (mhz) is the main radio frequency of the signal that controls a radio-controlled (RC) car.

I hope that answers your question. :)

it is a value that is given in a another table

1. You need to buy a R-134a recharging tool and at least one cannister of R-134a. You can find this in any auto parts store and even Wal-Mart. These come as a package and usually cost about $20 for the tool and 19 ounce can. Additional 12 ounce cans are about $6-$9. (In some locations around the country those prices could be much higher).

2. Locate the low pressure port. It is located next to the firewall on the passenger side of the car. Looking from the front of the car, it is in the far left rear of the engine compartment. The port is in a quite akward position, so you may want to detach the cannister from the tool and make sure you can manuver the tool and get it attached securely to the port. Exercise caution when connecting and disconnecting from this port as the port's internal valve (shrader valve) could be damaged or losened in this process and begin to leak. The shrader valve is the same type of valve found in tire valve-stem's but significantly larger. If your A/C system's valves are leaking (as seen during a visual inspection), a shrader valve tightening tool of the appropriate size is required to tighten it up.

3. Start the car and turn on the A/C.

4. Determine the pressure on the system from the guage on the tool. The ideal pressure depends on the ambient temperature (the cannister may have a chart to determine the ideal pressure), but the ideal pressure is probably somewhere between 40 and 45 psi. The A/C must be engaged to get a true pressure reading. You can see if the A/C is engaged by looking at the clutch which is located directly in front of the low pressure port toward the front of the engine compartment and lower in the compartment. The cluch has three knobs on the front of it which will be spinning if the clutch is engaged. If the clutch is not engaged, the pressure will read much too high. If the pressure is significantly too low the clutch will engage and disengage every couple of seconds. As you add the refrigerant this should stop.

5. If you need to add refrigerant, look in the portion of the tool where the cannister attaches and rotate the knob counterclockwise until the puncture device is lower than the rubber seal.

6. Screw the R-134a cannister securely into the tool.

7. Rotate the knob clockwise until it is completely down. This punctures the cannister.

8. Rotate the knob counterclockwise to release the refrigerant from the cannister. You should be able to hear and feel the refrigerant leaving the can and the can will begin to get colder.

9. While watching the gauge, slowly move the can back and forth from an upright to a sideways position while the cannister is being emptied. If you empty the entire cannister, turn the cannister upside down to get as much refigerant as possible out of the cannister.

10. When the pressure reaches the desired level, rotate the knob on the tool clockwise until it is compltely down.

11. Remove the tool from the port.

12. If you emptied the cannister, remove the cannister from the tool. DO NOT PUT YOUR HAND IN FRONT OF THE OPENING OF THE CANNISTER. SOME REFRIGERANT WILL STILL BE IN THE CANNISTER AND IT IS DANGEROUSLY COLD.

13. If more refrigerant is still needed, repeat the process.

usually the standard jacks for aircrafts have a mono phone and microphone jacks. the phone is easily identified because the opening is bigger. One receives a phone and phone low audio, while the other takes the mic audio and mic key to the audio panel selector.

Not usually. The car would have to be planted in the ground or the satellites camera would have to be at a shallow angle to earth. Yes and there will be to much atmosphere in the way that will distort the image, the best resolution by Google earth is 15 cm/pixel I really don't think so, I think the best resolution a satellite can reach is about 60mm per pixel and one letter or number is smaller than 60 mm it will only show up as a black or white spot. but this answer is open for debate

I think you mean 1/4W and 1/8W ratings for resistors. If so, it indicates wattage (power dissipation) ratings for resistors. Basically this specification for resistors shows maximum power that can be allowed to dissipate in the resistor. Wattage does not as such affect the value of resistor (it should remain with in % tolerance value specified when operated within specified wattage).

( P=I^2 x R). or (P = I x V)

P=Power, I = Current, R= Resistance, V = Voltage Once you know the power rating, you can calcutate how much current can be passed through a resistor of specific value without causing a damage to the component or circuit. For long term reliability always it is advisable to design with a margin (for 1/4W or 250mW e.g. design so that it is always certain % less than the rated e.g. operate at 200mW or less) - Neeraj Sharma

Students who pass the nursing board exam may wish to give a testimonial for other potential students. This will give them an idea of the amount of hard work involved in becoming a nurse.

Voltage is applied between the collector and emitter. A signal is applied between the base and emitter. The input signal will control how much the transistor turns on and the larger current flowing across the Collector/Emitter will be the same, but larger, than the input. Therefore amplified.
To keep the transistor switched on and to prevent the input signal switching it off, the transistor has to be biased on. This is usually done with a network of resistors on the base, raising the voltage to keep it conducting.

non- inductive load is without motor and transformer loads are non-inductive load,

purely resistive are capacitive loads

phase angle is unity are leading PF

A non-inductive load is a load whose current does not change instantaneously.