Microwave Devices and Circuits (samuel Liao)

for download book visit:
Microwave Devices Book [pdf]

Natural beauty

natural beauty of south america:

Know what is face detection face detection

                                       for detail visit:https://drive.google.com/file/d/0B0hRtuMP07n-VW9Uc1cyUzc1bjA/edit?usp=sharing

see video visit:http://www.youtube.com/watch?v=zT6FA_zTLPs
download photos visit:
https://drive.google.com/folderview?id=0B0hRtuMP07n-UjQ1dnNfRE1FQWc&usp=sharing
for download pdf files:

https://drive.google.com/file/d/0B0hRtuMP07n-M01FYkx0STM0MEU/edit?usp=sharing


https://drive.google.com/file/d/0B0hRtuMP07n-SmFjeUZpZm5ISTQ/edit?usp=sharing


https://drive.google.com/file/d/0B0hRtuMP07n-LXpibHJNZFM1V0U/edit?usp=sharing

http://homepages.cae.wisc.edu/~ece738/notes/Yang02.pdf

Let visit russian electronics lab:Know about all electronics components and buy online

Know about all electronics components and everything.

Visit:
http://www.electronics-lab.com/blog/?p=10288

know about anty theaf alarm

 



http://electronicsforu.com/electronicsforu/circuitarchives/view_article.asp?sno=1265&article_type=1&id=1088&tt=unhot&b_type=new#.VBFOH_mSzgQ

Know about arduino camera board

http://www.uctronics.com/arduino-camera-shield-arducam-for-uno-mega2560-board-p-1445.html

Know about alptop bettery connector hardware pin

Most laptop batteries are smart. This means that
the pack consists of two parts: the chemical cells
and the digital circuit. If the cells are weak, cell
replacement makes economic sense. While nickel-
based cells are readily available, lithium-ion cells
are commonly not sold over the counter, and
most manufacturers only offer them to authorized
pack assemblers. This precaution is
understandable given liability issues. Read also
about Safety Concerns and Protection Circuits .
Always use the same chemistry; the mAh rating
can vary if all cells are replaced.
A laptop battery may have only one weak cell,
and the success rate of replacing the affected cell
depends on the matching with the others. All cells
in a pack must have a similar capacity because
an imbalance shortens the life of the pack. Read
more about Can Batteries Be Restored? .
Furthermore, the state-of-charge of all cells being
charged for the first time should have a similar
charge level, and the open-circuit voltages should
be within 10 percent of each other. Welding the
cells is the only reliable way to get dependable
connection. Limit the heat transfer to the cells
during welding to prevent excess heat buildup.
The typical SMBus battery has five or more
battery connections consisting of positive and
negative battery terminals, thermistor, clock and
data. The connections are often unmarked;
however, the positive and negative are commonly
located at the outer edges of the connector and
the inner contacts accommodate the clock and
data. (The one-wire system combines clock and
data.) For safety reasons, a separate thermistor
wire is brought to the outside. Figure 1 illustrates
a battery with six connections.
Figure 1: Terminal
connection of a typical
laptop battery
The positive and negative
terminals are usually placed
on the outside; no norm
exists on the arrangement
of the other contacts.
Courtesy of Cadex
Some batteries are equipped with a solid-state
switch that is normally in the “off” position and
no voltage is present on the battery terminals;
connecting the switch terminal to ground often
turns the battery on. If this does not work, the
pack may need a proprietary code for activation,
and battery manufacturers keep these codes a
well-guarded secret.
How can you find the correct terminals? Use a
voltmeter to locate the positive and negative
battery terminals and establish the polarity. If no
voltage is available, a solid-state switch in the
“off” position may need activating. Connecting the
voltmeter to the outer terminals, take a 100-Ohm
resistor (other values may also work), tie one end
to ground, and with the other end touch each
terminal while observing the voltmeter. If no
voltage appears, the battery may be dead or the
pack will require a security code. The 100-Ohm
resistor is low enough to engage a digital circuit
and high enough to protect the battery against a
possible electrical short.
Establishing the connection to the battery
terminals should now enable charging. If the
charge current stops after 30 seconds, an
activation code may be required, and this is often
difficult if not impossible to obtain.
Some battery manufacturers add an end-of-
battery-life switch that turns the battery off when
reaching a certain age or cycle count.
Manufacturers argue that customer satisfaction
and safety can only be guaranteed by regularly
replacing the battery. Such a policy tends to
satisfy the manufacturer more than the user, and
newer batteries do not include this feature.
If at all possible, connect the thermistor during
charging and discharging to protect the battery
against possible overheating. Use an ohmmeter to
locate the internal thermistor. The most common
thermistors are 10 Kilo Ohm NTC, which reads
10kΩ at 20°C (68°F). NTC stands for negative
temperature coefficient, meaning that the
resistance decreases with rising temperature. In
comparison, a positive temperature coefficient
(PTC) causes the resistance to increase. Warming
the battery with your hand may be sufficient to
detect a small change in resistor value when
looking for the correct terminal on the battery.
In some cases the chemical battery can be
restored, but the fuel gauge might not work, is
inaccurate, or will provide wrong information.
After repackaging, the battery may need some
sort of initialization/ calibration process. Simply
charging and discharging the pack to reset the
flags might do the trick. A “flag” is a measuring
point to mark and record an event.
The circuits of some smart batteries must be
kept alive during cell replacement. Disconnecting
the voltage for only a fraction of a second can
erase vital data in the memory. The lost data
could contain the resistor value of the digitized
shunt that is responsible for the coulomb counter.
Some integrated circuits (IC) responsible for fuel
gauge function have wires going to each cell, and
the sequence of assembly must to be done in the
correct order.
To assure continued operation when changing the
cells, supply a secondary voltage through a 100-
Ohm resistor to the circuit before disconnection
and remove the supply only after the circuit
receives voltage again from the new cells. Cell
replacement of a smart battery has a parallel with
open-heart surgery, where doctors must keep all
organs of the patient alive.
Anyone repairing an SMBus battery needs to be
aware of compliance issues. Unlike other tightly
regulated standards, the SMBus allows some
variations, and this can cause problems when
matching battery packs with existing chargers.
The repaired SMBus battery should be checked for
compatibility before use. More information on
SMBus is available on www.sbs-forum.org and
www.acpi.info .
Simple Guidelines when Repairing Battery Packs
Only connect cells that are matched and have the
identical state-of-charge. Do not connect cells of
different chemistry, age or capacity.
Never charge or discharge Li-ion batteries without
a working protection circuit unattended. Each cell
must be monitored individually.
Include a temperature sensor that disrupts the
current on high heat.
Apply a slow charge only if the cells have
different state-of-charge.
Pay special attention when using an unknown
brand of cells. Some may not contain a high level
of intrinsic safety features.
Li-ion is sensitive to reverse polarization. Observe
correct polarity.
Do not charge a Li-ion battery that exhibits
physical damage or has dwelled at a voltage of
less than 1.5V/cell.
When repairing Li-ion, assure that each cell is
connected to a protection circuit.

what was done in physics today

On this day in 1933, while standing on the sidewalk where Southampton Row joins Russell Square in London, Leó Szilárd conceived the idea of a nuclear chain reaction. The idea made use of neutrons, which James Chadwick had discovered one year earlier, but not nuclear fission, which Otto Hahn, Lise Meitner and Fritz Strassmann would discover five years later. Szilárd proposed that if neutrons could trigger a nuclear reaction that both produced energy and further neutrons, the reaction would be self-sustaining. By 1939 Szilárd and Enrico Fermi had discovered neutron multiplication in uranium. Three years later, they and their collaborators built the world's first artificial self-sustaining nuclear reactor at the University of Chicago.

know what is difference between raspberry pi model B and B+

for more detail visit:
http://www.electronicsforu.com/newelectronics/articles/hitscc.asp?id=13096&group_type=cool_stuff

Here's a Remotely Programmable RTC Interfaced Microcontroller For Multiple Device Control.

for more detail visit:

http://electronicsforu.com/newelectronics/microcontrollers/hitscc.asp?title=Remotely+Programmable+RTC+Interfaced+Microcontroller+For+Multiple+Device+Control&id=4671&article_type=2

10 Microcontroller Based Projects You Must Not Miss

Looking for a microcontroller based project? From our collection of microcontroller based projects, we bring to you 10 super cool projects. Have fun!

for more detail

visit:

http://www.electronicsforu.com/newelectronics/articles/hitscc.asp?id=12922&group_type=cool_stuff

know about Millitary robot

We heard you are already liking our features with free ebooks, here's another collection of ebooks on Mechtronics and Robotics. Happy reading!

for more detail visit:
http://www.electronicsforu.com/newelectronics/articles/hitscc.asp?id=12674&group_type=cool_stuff

gate 2013 paper with complete sollution

for download PDF file  visit:

https://drive.google.com/file/d/0B0hRtuMP07n-WkJsQm44Yk9nMHc/edit?usp=sharing

how to double intetnet speed..watch video

visit :
http://youtube.com/watch?v=lG5cEik2ABY

amazing photos of jibo and jarvious

know about quad copter

see this rare file ..

https://drive.google.com/file/d/0B0hRtuMP07n-czltV1B3RDBvYUk/edit?usp=sharing

know about nano quadcopter

for more detail visit..http://www.snelflight.co.uk/QuadPod%20Nano.htm

know your knowledge about 8051 c programming

8051 microcontroller programming is the one of the basic programming to learn prograaming of micro controller and its hardware connection.

for steps to learn how programming into 8051 c language.

visit this link .:-
https://drive.google.com/file/d/0B0hRtuMP07n-b0dGcmdncV9ROGM/edit?usp=sharing

Gtu 7 th sem paper.rare

if u want to download 7th sem gtu exam papers so

click on below link..

https://drive.google.com/file/d/0B0hRtuMP07n-bGtiVVhGV05FWlE/edit?usp=sharing

Thyristor control light using ir remote control.

• In this project we use triac...used for which is  due to triigger by  the 89s52 microcontroller to the opto iso lator .

• The delayed firing angle is displayed into led display.

The output hwere in should have the motor or the lamp here,the output which varies which indicates that the intensity of the lamp or speed of the motor is varies.

• Now we will try to operate this ,once we press it is based on the delay,more hte delay less the power.
• now suppose if i take only 1 ms delay u find the the lamp is in full intensity almost,i make 2 it down a little,3,4,5,6.
• when u press 7 no u find the lamp is in down intisity,when press 8 the intensity is fallen.

when u press 9 it is al most vary to very very low. if i make 0 it stops.

for more detail...visithttps://drive.google.com/file/d/0B0hRtuMP07n-VzMxamNyZ2tFMEE/edit?usp=sharing

visit video https://drive.google.com/file/d/0B0hRtuMP07n-dTlaSExlMkR3Q2M/edit?usp=sharing

Travelling cellphone charger

Mobile cellphone charger

While travelling charging of mobile battery is great problem because power supply source is not generally accessible. Here is a simple project using very common electronics components for charging mobile battery using AA cells.

Circuit descriptions of mobile cellphone charger

The main part of the circuit mobile cellphone charger is timer IC NE555, used to charge and monitor the voltage level. IC₁ get control voltage to pin 5 by zener diode ZD₁­. Threshold pin 6 and trigger pin 2 is supplied with a voltage set by VR₁ and VR₂ respectively. The trigger pin 2 of IC₁ is below 1/3V_CC when discharge battery is connected to the circuit as a result flip-flop of IC₁ is switched on to take output pin 3 high. The process is reversed when battery is fully charged of charged battery is connected. Here transistor T₁ used to enhance the charging current from output pin 3 of IC₁. Adjust potentiometer VR₁ and VR₂ as per require.

LED status for different charging conditions

Load across the output	Output frequency (at pin 3)	LED1
No battery connected	765 kHz	On
Charging battery	4.5 Hz	Blink
Fully charged battery	0	Off

 PARTS LIST

Resistors (all ¼-watt, ± 5% Carbon)

R₁ = 390 Ω

R₂ = 680 Ω

R₃ = 39 Ω/1W

R₄ = 27 KΩ

R₅ = 47 KΩ

R₆ = 3.3 KΩ

R₇ = 100 Ω/1W

VR₁, VR₂ = 20 KΩ

Capacitors

C₁ = 0.001 µF (ceramic disc)

C₂ = 0.01 µF (ceramic disc)

C₃ = 4.7 µF/25V (Electrolytic )

Semiconductors

IC₁ = NE555 timer IC

T₁ = SL100 or any Medium power general purpose NPN transistor like: 2N4922 , 2N4921,2N4238, FCX1053A

ZD₁ = 5.6 V/1W

LED₁

Miscellaneous

SW₁ = On/off switch

1.5V*8 AA cells

Mobile connector

..Read more http://electronicsproject.org/mobile-cellphone-charger/

 

other circuit is...below..

Component of travvelling charger.

R1 = 1K
R2 = 470R
R3 = 4.7K
R4 = 270R
R5 = 27R
C1 = 100uF-25V
D1 = Green LED
D2 = 4.7V/1W Zener
B1 = 1.5Vx4 Cells
S1 = On/Off Switch
Q1 = BC548
Q2 = SK100

The inside of camera

 For more details visit: https://drive.google.com/file/d/0B0hRtuMP07n-X2kxRkxuZFZXVEE/edit?usp=sharing


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