IDO Regulator

The circuit shown above is of a practical LDO regulator circuit using IC LM2941 from National semiconductors. LM2941 is an integrated LDO voltage regulator IC whose output can be adjusted. The IC has many good features like thermal shutdown, transient protection, short circuit protection etc. The reverse polarity protection feature makes this IC very applicable in automotive applications. The output voltage can be adjusted from 5V to 20V and the dropout voltage is 0.5V at 1A output current.
In the circuit the voltage divider network comprising of R1 and R2 sets the output voltage. Capacitor C2 is the input filter which is very essential if the regulator circuitry is situated away from the rectifier+filter module. Capacitor C1 is the output filter while S1 is the ON/OFF switch. Resistor R3 is used to ensure the necessary 300mA pull up current which is necessary for proper shutdown when the switch S1 is made open.

Notes.
The circuit must be assembled on a good quality PCB.
A heat sink is required for application above few hundred milli amps.
Vout = 1.275 ((R1 + R2)/R1)
During calculation select R1=1K and solve for R2.
Selecting R1 = 1K will make the input bias current error of the adj pin negligible.
Reducing the value of C1 below 22uF will induce instabilities and also this capacitor must be placed as close as possible to the IC on the PCB.

Read more: http://www.circuitstoday.com/ldo-regulator#ixzz1PYuKlUfp

Night security light

Night security light
  
Here is a simple circuit switches on a light around 2 hours after midnight, the time at which most of the robberies taking place.
This simple circuit is build around a CMOS IC 4060 to obtain the required timing. During day time the LDR has low resistance and keeps the pin 12 of the IC1 high, preventing the IC1 from oscillating. When it is dark the LDR resistance becomes high and the pin 12 of IC1 becomes low and the IC starts oscillating, which indicated by the flashing of LED D3.The values of the timing components R1, R2, C4 are so selected that the out put pin3 of IC1 goes high after 8 hours. That means the high output drives the triac to switch on the lamp around 2’O clock. At morning, the LDR resistance drops and the pin 12 of IC1 goes high and stops the oscillation, making the lamp OFF. The switch S1 can be used to manually ON the lamp. The capacitor C2 prevents false triggering.
Notes.
Assemble the circuit on a good quality PCB or common board.
The LDR can be general purpose LDR.
The light sensitivity can be adjusted using the preset R6.
The IC1 must be mounted on an IC holder

Read more: http://www.circuitstoday.com/night-security-light#ixzz1PYwEomYK

Simple UPS

Simple UPS
  
This is the circuit diagram of a simple UPS that can deliver 12V unregulated and 5V regulated DC. The transformer T1 steps down the mains voltage to 12V AC and then the bridge B1 rectifies it. The rectified signal is smoothed by the capacitor C1.When the mains supply is available the battery will be charged via diode D3 and the regulator IC gets supply via diode D5. 12V and 5V DC will be available at the output terminals. When mains supply is not available the battery supplies current to the regulator IC and to the 12V DC terminal through diode D4.Also, the diode D3 blocks reverse flow of current during battery mode. Capacitors C2 and C3 acts as filters.
Notes.
Assemble the circuit on a good quality PCB.
The transformer T1 can be a 230V AC primary, 12V secondary,3A step-down transformer.
The bridge B1 can be a 2A bridge. If such a bridge is not available, make one using four 1N4007 diodes.
The capacitor C1 must be rated at least 25V

Read more: http://www.circuitstoday.com/simple-ups-construction#ixzz1PX9rSyOJ

Fuse with status indicator

Fuse with status indicator

   
Here is the circuit diagram of a fuse that has an automatic status indicator. This circuit can be added to circuit that operates from 12V DC. As long as the fuse is intact, the LED D3 will glow continuously and when the fuse blows off the LED will start and continue blinking.
The first part of the circuit includes an astable multivibrator built around transistors Q1 and Q2.The output of the multivibrator is coupled to the base of Q3 via diode D2.When the fuse is intact the base of Q3 will be pulled to a positive voltage by the resistor R5. The transistor will be ON and the LED D3 remains glowing. When the fuse of blown off, the base of Q3 will no longer be pulled to positive voltage and now the only biasing available at the base of Q3 will be the output from the astable multivibrator. Now the transistor Q3 will start switching in the frequency of astable multivibrator and the LED will blink in accordance.
Notes.
The circuit can be assembled on a Vero board.
This fuse circuit can be incorporated with any circuit that operates from 12V DC.
The type no of the transistors are not very significant and almost any NPN transistors will do the job.
The fuse F1 can be a metal wire fuse with your required rating.

Read more: http://www.circuitstoday.com/fuse-with-status-indicator#ixzz1PX8A1BQj

Remote control tester

Remote control tester
 
This is a simple remote controller tester circuit  based on infrared sensor IC TSOP 1738. When the IR waves fall on the sensor it output changes to low state.This makes the transistor Q1 ON and LED will blink according to the code contained in the signal.So for press of each button the LED blinks in different ways.This is a good indication of the working of remote.The diode D1drops 0.7 V to give the IC ~ 5V supply from the available 6V .R2 is a current limiting resistance.
Notes .
Use a 6V battery to power up the circuit.
This circuit can be used to test remotes operating in the 38Khz carrier frequency.Almost all remotes fall into this category so no problem.
We have more Remote Cir

Read more: http://www.circuitstoday.com/remote-controll-tester-circuit#ixzz1PSIbjaqW

Brightness controller for low power lamps

Brightness controller for low power lamps

  
The circuit given here can be used to control the brightness of low power incandescent lamps. The circuit is based on IC NE555 which is wired as an astable multivibrator with variable duty cycle. The output of IC is connected to the base of transistor Q1.The Q1 drives the lamp. The duty cycle of the multivibrator can be varied by varying the POT R4.As a result, the brightness of the lamp varies according to the position of the POT R4.The same circuit can be also used for speed control of small DC motors.
Notes.
The lamp L1 can be a 6V / 200 mA lamp.
The switch S1 can be SPST ON/OFF switch.
The IC1 must be mounted on a holder.
The circuit can be wired on a good quality PCB or common board.

Read more: http://www.circuitstoday.com/brightness-controller-for-low-power-lamps#ixzz1PSGZtjfu

Car Audio Amplifier Circuit

Car Audio Amplifier Circuit
         
A simple low power car stereo amplifier circuit based on TDA 2003 is shown here. The
circuit uses cheap, readily available components and it is very easy to construct.
TDA2003 is an integrated car radio amplifier from ST Micro electronics that has a lot of
good features like short circuit protection for all pins, thermal over range low
harmonic distortion, low cross over distortion etc.
In the circuit given here each TDA2003 is wired as a mono amplifier operating from a 12V
supply. Resistors R2 and R3 forms a feedback network that sets the amplifiers gain. C7
is the input DC de-coupling capacitor and C5 couples the speaker to the amplifiers
output. C4 is used for improving the ripple rejection while C1 and C2 are employed for
power supply filtering. C3 and R1 are used for setting the upper frequency cut-off.
Network comprising of C6 and R4 is used for frequency stabilization and to prevent oscillation.
Notes.
Assemble the circuit on a good quality PCB.
Heat sinks are necessary for both ICs.
The circuit can be operated from 12V DC.
S1 is the ON/OFF switch.
Other Audio amplifier c

Read more: http://www.circuitstoday.com/car-stereo-amplifier-using-tda2003#ixzz1PRhuXlJE

Converter Frequency to Voltage

Converter F to V

F to V Converter Circuit using LM555 Timer

Here is a very simple circuit diagram of a frequency to voltage (F to V) converter. Such
a circuit finds numerous applications in projects like digital frequency meters,
tachometers etc. The circuit is mainly based on a LM555 timer IC. The IC is wired in
mono shot mode to convert the input frequency into a fixed pulse width, variable
frequency PWM signal. Resistors R4 and capacitor C2 provides the necessary timing for
the circuit. The transistor T1 forms a discharge path parallel to C2 which is necessary
for re triggering the IC. Capacitor C1 acts as an input DC decoupler.
Notes.
The circuit can be assembled on a Vero board.
Use 12V DC for powering the circuit.
LM555 must be mounted on a holder.
The output of the circuit is not a pure DC but a PWM waveform. Additional circuitry is
required to convert this PWM waveform to pure DC.

source  www.circuitstoday.com

30 Watt Amplifier TDA2040

30 Watts Audio amplifier Circuit

 

30 watt audio amplifier circuit using TDA2040 is shown here. TDA2040 is a Class AB
monolithic integrated audio amplifier available in Pentawatt package. The IC has low
harmonic distortion, low cross over distortion and has a built in circuitry for short circuit protection.
In the circuit two TDA2040 ICs are wired in BTL (Bridge Tied Load) configuration in
order to deliver 30W output into an 8 ohm speaker at +/-16V DC supply. Capacitor C1 is
the input DC decoupling capacitor. Network comprising of components R2, C4, R3 provides
feedback for IC1 while R7, C6, R8 network provides feedback for IC2. Network C5, R5 and
C9, R9 provides high frequency stability. Capacitors C2, C3 filters the positive supply
rail while capacitors C7, C8 filters the negative supply rail.Notes.
A well designed and good quality PCB will always improve sound quality.
Use +/-16V DC dual supply for powering the amplifier.
Heat sinks are necessary for IC1 and IC2.
Load can be an 8 ohm speaker.
C2, C7 must be rated 25V and other electrolytics can be 10 or 15V.

Read more: http://www.circuitstoday.com/30-watt-amplifier-using-tda2040#ixzz1PNYZLPXZ

Hi Fi Amplifier 6 Watt

TDA2613 Hi Fi audio amplifier
 

A 6 watt audio amplifier circuit using TDA2613 is shown here. TDA2613 is an integrated
Hi-Fi  audio amplifier IC from Philips Semiconductors. The IC is switch ON / switch OFF
click proof, short circuit proof, thermally protected and is available in 9 pin single in line plastic package.
In the given circuit, TDA2613 is wired to operate from a single supply. Capacitor C4 is
the input DC decoupler while capacitors C5, C6 are power supply filters. Input audio is
fed to the non inverting input through capacitor C4. Inverting input and Vp/2 pins of
the IC are tied together and connected to ground through capacitor C3. Capacitor C2
couples the speaker to the ICs output and the network comprising of capacitor C1 and
resistor R1 improves the high frequency stability.Notes.
Assemble the circuit on good quality PCB.
Supply voltage (Vs) can be anything between 15 to 24V DC.
Heat sink is necessary for TDA2613.
Do not give more than 24V to TDA2613.
We have more audio amplifier circ

Read more: http://www.circuitstoday.com/hi-fi-audio-amplifier-circuit#ixzz1PNVzfD1x

Audio mixer dan Lampu Flasher 24 volt

Single transistor audio mixer
 

Many audio mixer circuits have been published here. But I think, this one is the
simplest of them. This very simple audio mixer circuit uses only one transistor. The
base emitter junction of the transistor is biased by the diodes D1 and D2.The signals to
be mixed are directly coupled to the base of Q1.Each input lines are current limited by
using a 33K resistor. With the used component values the collector current is around 1mA.
Notes.
The circuit can be assembled on a Vero board.
The circuit can be powered from 15V DC.
Gain of the individual channels can be adjusted by adding a 10K POT in series to the lines.

Read more: http://www.circuitstoday.com/single-transistor-audio-mixer#ixzz1PMB3sU8r

24v Flasher circuit
 
The circuit shown here works from 24V DC and can flash two 24V bulbs alternatively. The
circuit is nothing but an astable multivibrator operating at 1Hz and 50% duty cycle. The
lamp to be flashed is connected in place of the collector resistor (Rc) of a typical
design. 2N3055 transistors which are well known for their ruggedness are used here. They
can handle collector currents up to 10A. So a wide range of lamps (in terms of wattage)
can be connected to this circuit. Circuit Diagram. Notes. Assemble the circuit on a good
quality PCB. Use 24V DC for powering this circuit. Lamp L1 and L2 can be 24V/25W type.
It is advised to fit the transistors with heat sinks. Flashing rate can be modified by
adjusting the values of R1, R2, C1 and C2.

Read more: http://www.circuitstoday.com/category/lighting-circuits#ixzz1PMCTWF1Z

Car Head Lights Turn Off Circuit

Car Head Lights Turn Off Circuit
  
This circuit when setup in a car automatically turns off the head light after a preset
time after the ignition switch is turned off.So you can walk out easily from the dark
garage in the light of your car.
When the ignition switched on first the voltage from battery is fed to the relay through
diode D1.When the ignition switch is turned off it produces a negative going pulse at
the pin 2 that triggers the timer. The output of the IC goes high for the time set by R1
 .This makes the transistor Q1 to conduct to energize the relay to drive the
headlight.After the set time the light goes off.With the value of components used you
can make a setting from 10 S to 60 S.
Notes
Assemble the circuit on a good quality PCB or common board.
Fit the potentiometer on somewhere on the dashboard so that  you can easily set the timing.

Read more: http://www.circuitstoday.com/automatic-head-lights-turn-off-
circuit#ixzz1PHTywkkF
Jadual Acara Tv Hari Ini
 Acara Tv Hari ini untuk RCTI,SCTV,METROTV,INDOSIAR dapat dilihat langsung dibawah ini atau akses langsung link -nya
http://www.rcti.tv/jadwal
http://www.sctv.co.id/view.php?0,0,1,jadwal,1237715964
http://www.indosiar.com/program/jadwalacara
option=com_content&task=view&id=20&Itemid=231
http://www.globaltv.co.id/schedule
http://www.tvone.co.id/program
http://www.metrotvnews.com/read/schedule
Dari berbagai sumber

Kabel Tv Amplifier dan Am Receiver

Kabel Tv Amplifier
  
This is a very simple cable TV amplifier using two transistors. This amplifier circuit
is most suitable for cable TV systems using 75 Ohm coaxial cables and works fine up to
150MHz. Transistor T1 performs the job of amplification. Up to 20dB gain can be expected
from the circuit.T2 is wired as an emitter follower to increase current gain.
Notes.
The circuit can be assembled on a Vero board.
Use 12V DC for powering the circuit.
Type no of the transistors are not very critical.
Any medium power NPN RF transistors can be used in place of T1 and T2.
This is just an elementary circuit. Do not compare it with high quality Cable TV
amplifiers available in the market.

Read more: http://www.circuitstoday.com/cable-tv-amplifier#ixzz1PHLHQPsR

Am Receiver Circuit

  
Here is a low cost AM receiver circuit that can be tuned from around 550 to
1100 KHz. Three transistors are used in this project. The transistors Q1 and Q2 are
wired as a compound transistor pair in which Q1 is an emitter follower and Q2 is a
common emitter amplifier. The emitter follower prevents the loading of tank circuit,
while the common emitter amplifier necessary voltage gain. The L1 and C2 forms the tank
circuit.The L1 also does the job of antenna.The series combination of R6 and R7 gives a
regenerative feedback between output of the Q2 and tank circuit. The transistor Q3
performs the demodulation of the carrier signal. It also provides amplification the
demodulated signal. The audio output is coupled out from the collector of Q3 via the
capacitor C3.Capacitor C6 provides some noise filtering. Circuit diagram. Notes. The
circuit can be assembled on a general purpose PCB. Use a 9V PP3 battery for powering the
circuit. R7 can be used to adjust the sensitivity and selectivity of the circuit. A high
impedance head phone can be used for listening the radio. For L1 make 60 turns of 26 SWG
enameled copper wire on a 3/8…

Read more: http://www.circuitstoday.com/category/radio-circuits#ixzz1PHJxCcCE

Drift City On Line US

Info Game

  Download game di www.gamescampus.com
ber daya alam yang dimiliki Bumi ini kian menipis hingga ditahap krisis. Dan salah satu sumber daya vital yang mengalami krisis bagi umat manusia tersebut, tak lain adalah minyak bumi. Dan disaat semua bangsa-bangsa didunia ini sibuk dengan krisis minyak bumi, muncul wacana baru yang menjanjikan harapan bagi umat manusia.
Wacana tersebut adalah, telah ditemukannya sumber daya energi baru yang bisa menggantikan minyak bumi bernama MITTRON. Sumber daya ini terletak di belahan dunia Pasifik Utara, atau tepatnya sebuah pulau kecil bernama Mittron Island. Dan sumber daya Mittron inilah yang diprediksi akan bisa menjadi satu-satunya sumber energi yang bisa menggantikan minyak bumi.
Alhasil, sejak dikembangkan pada tahun 2007 oleh OMD (Organization for Mittron Development), Mittron telah tampil sebagai bahan bakar multifungsi yang bisa dimanfaatkan berbagai perangkat transportasi. Semua kendaraan yang menggunakan bahan bakar Mittron diklaim akan mampu berjalan dengan lebih cepat, lebih hemat energi, dan juga lebih ramah lingkungan.
OMD, sebagai lembaga tunggal yang berwenang dalam pengembangan Mittron, secara perlahan menerapkan segala kebijakan adminstratif dalam pendistribusian Mittron kepada semua moda transportasi diseluruh dunia. Bahkan, tidak hanya administrasi & distribusi, OMD telah sukses menjalankan misinya untuk menguasai Pulau Mittron dengan mendirikan sebuah kota berskala kosmopolitan bernama
Moon Palace. Kelak, kota ini akan menjadi rujukan bagi seluruh dunia dalam
memanfaatkan sumber daya Mittron tersebut.
Namun, seiring dengan berjalannya waktu, ternyata tidak semua orang menyukai eksistensi dari OMD. Sekelompok mobil misterius, sebut saja HUV, melakukan aksi teror di seluruh bagian dari kota Moon Palace. Mereka membajak seluruh proses distribusi Mittron dari Pulau Mittron keseluruh dunia. Bahkan, mereka juga tak segan-segan untuk bertindak anarkis dan kriminal terhadap semua kendaraan yang melintas di kota Moon Palace.
Dan tugas kalian untuk mengembalikan ketentraman di seluruh bagian dari Pulau Mittron dimulai dari sini....

 

Flashing Batteres Monitor with 3 Led Indikator

Flashing Batteres Circuit

 
Description. Here is a simple circuit in which an LED will continue flashing as long as
the voltage of the battery to be monitored is above the set level.The transistors Q1 and
Q2 are wired as a complementary astable multivibrator.The circuit can operate from a
voltage range from 6V to 12V. The voltage level at which LED has to stop flashing can be
set by adjusting the preset R4.When the battery voltage reaches the threshold the
flashing frequency decreases and when the voltage goes below the threshold the LED
becomes OFF.The diode D1 is used to compensate the changes in the base emitter voltage
of Q1 due to temperature changes. Circuit diagram with Parts list. Notes. Assemble the
circuit on a general purpose PCB. Batteries from 6V to 12V can be monitored by this
circuit. The diode D1 must be a Schottky diode.
Read more: http://www.circuitstoday.com/category/battery-related#ixzz1PCfjcIQ0

3 Led Batteres Monitor

  
Description. This is the circuit diagram of a 3 LED bar graph type battery monitor
circuit that is ideal for monitoring the voltage level of an automobile battery.When
battery voltage is 11.5V or less transistor Q1 will be On and the LED D1 will be
glowing.When battery voltage is between 11.5 and 13.5V, the transistor Q2 will be On and
the LED D2 will be glowing.When battery voltage is above 13.5V the transistor Q3 will be
On and the LED D3 will be glowing. Circuit diagram with Parts list. Notes. Assemble the
circuit on a general purpose PCB. The battery to be monitored can be connected between
the terminals namely A and B. It is always better to use LEDs of different colour.

Read more: http://www.circuitstoday.com/category/battery-related#ixzz1PCgjWlRR

Driver Lampu Neon 8 watt dan Indikator Led Panggilan Masuk

Driver Lampu Neon 8 watt

Here is the schematic of a simple flouroscent lamp driver circuit based on two transistors.The circuit uses capacitive ballasting for driving the tube.An 8 W  standard flouroscent tube can be efficiently driven using the circuit.

The two  transistors (2Sc 1983)  with associated components forms a oscillator  around
1KHz.The oscillator is wired so that  saturation condition of the transistors are 
prohibited.This  adds on to the efficiency of the circuit.The circuit produces a clean
sine wave with very less noise.
Circuit diagram with Parts list.
Notes.
Use a 12 V battery as the DC voltage source.
Use a 8W florescent lamp as load.
The winding details(no of turns) are given in the circuit.Use  0.8 mm dia enameled
copper wire for primary and 0.4 mm dia enameled copper wire for secondary.The core can
be a ferrite core.The primary should be wound first and secondary on top of it.

Read more: http://www.circuitstoday.com/8w-flouroscent-lamp-driver#ixzz1PBFqzXxV

Kode Kunci Satu Transistor

One transistor code lock
 
This is of course the simplest electronic code lock circuit one can make. The circuit uses one transistor, a relay and few passive components. The simplicity does not have any influence on the performance and this circuit works really fine.
The circuit is nothing but a simple transistor switch with a relay at its collector as load. Five switches (S0 to S4) arranged in series with the current limiting resistor R2 is connected across the base of the transistor and positive supply rail. Another five switches (S5 to S9) arranged in parallel is connected across the base of the transistor and ground. The transistor Q1 will be ON and relay will be activated only if all the switches S0 to S4 are ON and S5 to S9 are OFF. Arrange these switches in a shuffled manner on the panel and that it. The relay will be ON only if the switches S0 to S9 are either OFF or ON in the correct combination. The device to be controlled using the lock circuit can be connected through the relay terminals. Transformer T1, bridge D1, capacitor C1 forms the power supply section of the circuit. Diode D2 is a freewheeling diode. Resistor R1 ensures that the transistor Q1 is OFF when there is no connection between its base and positive supply rail.Circuit diagram.
Notes.
This circuit can be assembled on a Vero board.
Switch S1 is the lock’s power switch.
The no of switches can be increased to make it hard to guess the combination.
Transistor 2N2222 is not very critical here. Any low or medium power NPN transistor will do the job.

Read more: http://www.circuitstoday.com/one-transistor-code-lock#ixzz1PA2yxZbN


Tv Remote Jammer

  

Here is the circuit diagram of simple but highly effective TV remote jammer circuit.
Most of the TV remotes have 38KHz operating frequency. A flood of IR beams in the same
frequency can easily confuse the TV receiver and this is the operating principle of our
jammer. The circuit is nothing but an astable multivibrator based on NE555 IC. The
output of NE555 is amplified using a PNP transistor SK100 to drive the IR LEDs. Not only
TV remotes, but any IR remotes operating in the 38KHz frequency region can be also
jammed by using this circuit.Circuit diagram.
Notes.
The circuit can be assembled on a Vero board.
Use a 9V PP3 battery for powering the circuit.
Mount the IC on a holder.
POT R4 can be adjusted to exactly match the jammer’s frequency to the remotes frequency.
This adjustment is very essential for effective jamming.

Read more: http://www.circuitstoday.com/tv-remote-jammer#ixzz1PB4sofv5

Rangkaian Subwoofer dan Port USB

Subwoofer Filter Circuit Using Op-Amp TL072
 
Here is a simple subwoofer filter circuit that can be powered by a 12V DC. This circuit
is very useful in automotive applications subwoofer. The circuit is a low pass filter
whose pass frequency can be set between 60 to 160 Hz
Subwoofer Filter Circuit Using Op-Amp TL072
Op-Amp TL072
The circuit is built around the TL072 dual op amp IC BIFET. Of the two operational
amplifiers inside the chip, IC1A is wired as a buffer. The left and right audio inputs
after mixing is fed to the input of the IC1A using the DPDT switch S1. Switch S1 is the
phase control switch which can be used to make the subwoofer in phase with other
speakers. When S1 is in position 2, 180 degree phase shift will be induced.POT R7 can be
used for controlling the level. IC1B forms the low pass filter whose pass frequency can
be controlled by adjusting the dual gang POT R13.
Note:
The circuit can be powered from 12V DC.
C5 and C6 must be polyester capacitors.
POT R13 can be used for adjusting the pass frequency.
POT R7 can be used for adjusting the level.

Source   skema-amplifier.blogspot.com




12 volt DC Power Supply from USB port

    
The circuit given below infact is a 5 volt to 12 volt converter. It uses the 5 Volts
from USB port and converts it to 12 volts DC with the help of IC LT1618.
Description :
Using this circuit we can convert 5V DC from the computer USB port to 12V DC and a
circuit like this will find a lot of application in USB powered systems. The heart of
this circuit is IC LT1618 which is a constant current, constant voltage boost converter.
The IC has a wide input voltage range of 1.8 to 18V DC and output voltage can be up to 35V DC.
In the circuit resistors R1, R2 sets the output voltage. Pin number 9 is the shutdown
pin, less than 0.3V to this pin will shut down the IC. Pin number four is the current
sense adjust pin. The current sense voltage can be reduced by applying a DC voltage to
this pin. If this adjustment is not needed connect this pin to ground and you can omit
components R3, R5 and Q1.
Circuit diagram of 12 volts dc power supply:
Circuit Diagram-12Volts DC power supply from USB port
Notes :
C2 and C3 must be rated at least 15V.
Less than 0.3V at the shutdown pin will shutdown the IC.
Output voltage is governed by the following equation R1 = R2 (  (Vout /1.263V) -1).

Read more: http://www.circuitstoday.com/12v-from-usb-port#ixzz1P9sMcj2v

Power Supply Kamera Digital

DIGITAL CAMERA PSU AND BATTERIES CHARGER

 
This ambit was created for agenda cameras. It's accepted the agenda cameras accept ample
ability consumption. For archetype my camera Minolta E223 requires about 800 mA. In
convenance a mains ability accumulation or aerial accommodation NiMH accumulators
(batteries) can amuse this demand.
This ambit consists of two parts, charger and adapter. The transformer, rectifier arch
and absorber condensator are common. Adapter is absolutely artlessly its capital
allotment is an adjustable voltage regulator LM 317 according to accepted setting.
Output is a acceptable for camera jack plug. Voltage can be adapted in ambit 2-9 V.
In the charger ambit a 7805 anchored voltage regulator works as accepted architect
assured connected accepted during charging. This charging accepted can be adapted with
the 100 /1W potentiometer in ambit about 50-300 mA adumbrated by a baby accepted
barometer instrument. From one to four batteries can be answerable simultaneously. The
about-face charge be set according to cardinal of batteries, and charging accepted of
batteries accustomed by architect charge be adjusted. This ambit doesn't admeasurement
charging time and charging action of batteries. Manufacturers accord charging time,
usually 14-16 h. I apparent this botheration with a simply, bargain automated mains
timer. I anticipate its accurateness is sufficient.
Source   skema-amplifier.blogspot.com

25Watt Audio Amplifier Mosfet

25Watt Audio Amplifier Mosfet IRF530-IRF9530

The following is a circuit of 25Watt High Quality power amplifier Mosfet IRF530-IRF9530
from Motorola's transistors are employed in the preceding stages. The supply rails
prudentially voltage was kept at the rather low value of + and - 32V.
Skema Rangkaian 25Watt Audio Amplifier Mosfet
Note:
Q6 & Q7 must have a small U-shaped heatsink.
Q8 & Q9 must be mounted on heatsink.
Adjust R11 to set quiescent current at 100mA (best measured with an Avo-meter connected
in series to Q8 Drain) with no input signal.
A correct grounding is very important to eliminate hum and ground loops. Connect to the
same point the ground sides of R1, R4, R9, C3 to C8. Connect C11 to output ground. Then
connect separately the input and output grounds to power supply ground.
List Component

R1,R4_________47K 1/4W Resistors
R2____________4K7 1/4W Resistor
R3____________1K5 1/4W Resistor
R5__________390R 1/4W Resistor
R6__________470R 1/4W Resistor
R7___________33K 1/4W Resistor
R8__________150K 1/4W Resistor
R9___________15K 1/4W Resistor
R10__________27R 1/4W Resistor
R11_________500R 1/2W Trimmer Cermet
R12,R13,R16__10R 1/4W Resistors
R14,R15_____220R 1/4W Resistors
R17___________8R2 2W Resistor
R18____________R22 4W Resistor (wirewound)
C1___________470nF 63V Polyester Capacitor
C2___________330pF 63V Polystyrene Capacitor
C3,C5________470µF 63V Electrolytic Capacitors
C4,C6,C8,C11_100nF 63V Polyester Capacitors
C7___________100µF 25V Electrolytic Capacitor
C9____________10pF 63V Polystyrene Capacitor
C10____________1µF 63V Polyester Capacitor
Q1-Q5______BC560C 45V 100mA Low noise High gain PNP Transistors
Q6_________BD140 80V 1.5A PNP Transistor
Q7_________BD139 80V 1.5A NPN Transistor
Q8_________IRF530 100V 14A N-Channel Hexfet Transistor
Q9_________IRF9530 100V 12A P-Channel Hexfet Transistor

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