Wednesday, December 26, 2012

Sequential Turn Lights Driver Four LED left and right sequence Particularly suited to motorcycles

Sequential Turn Lights Driver Four-LED left and right sequence Particularly suited to motorcycles


R1_____________500K  1/2W Trimmer Cermet or Carbon
R2______________47K 1/4W Resistor
R3,R4____________1K 1/4W Resistors
R5,R6,R7,R8_____10K 1/4W Resistors

C1_______________1µF 63V Polyester or electrolytic capacitor
C2_____________220µF 25V Electrolytic capacitor

D1-D8__________LEDs Yellow ultra-bright types

Q1,Q2,Q3,Q4___BC337 45V 800mA NPN Transistors

IC1____________7555 or TS555CN or TLC555CP CMos Timer IC
IC2____________4017 Decade counter with 10 decoded outputs IC

SW1____________Vehicle Turn Lights switch (See Comments)

Battery_________12V Vehicle battery


This device was designed on request and allows sequential operation of four Leds either to left or right direction, obtained by means of a 7555 CMos timer IC (IC1) wired as an astable multivibrator driving a Decade counter (IC2). This IC is set to count a sequence of four by connection of pin #10 to pin #15, but any sequence count in the 2-10 range can be set by choosing the appropriate pin connection. Obviously, LEDs, Transistors and their respective Base-limiting resistors must also be added or omitted accordingly.
R1 is a variable resistor (Trimmer), used to set the desired speed of the LEDs. SW1 is a change-over switch that should already exist in your motorcycle, having a center-off position and Turn-left and Turn-right positions.
D1, D3, D5 and D7 are the Turn-left LEDs; D2, D4, D6 and D8 are the Turn-right LEDs.
For a motorcycle they are arranged on a single board about 20 - 25 cm wide as shown in the image below. The outer red LEDs are the tail/brake lights and can be driven by a circuit like the LED driven tail/brake Light Cluster available on this website.

Sequential Turn Lights example


  • The use of high brightness, high efficiency yellow LED types of suitable size is mandatory.
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7 Watt Audio Power Amplifier Circuit Schematic


This small amplifier is constructed around the TDA2003 IC, capable of delivering 4Wrms at 4ohms. The TDA 2003 has improved performance with the same pin configuration as the TDA 2002. The additional features of TDA 2002, very low number of external components, ease of assembly, space and cost saving, are maintained. The device provides a high output current capability (up to 3.5A) very low harmonic and cross-over distortion. Completely safe operation is guaranteed due to protection against DC and AC short circuit between all pins and ground, thermal over-range, load dump voltage surge up to 40V and fortuitous open ground. A conventional direct current can be connected as supply.

Circuit's picture:


Circuit diagram:

Circuit diagram


  • R1 = 470R
  • R2 = 47R
  • R3 = 100R
  • R4 = 1R
  • C1 = 1822pF
  • C2 = 100nF-63V
  • C3 = 100nF-63v
  • C4 = 10uF-25V
  • C5 = 470uF-25V
  • C6 = 1000uF-35v
  • C7 = 1000uF-35V
  • IC1 = TDA2003


  1. Music power output: 7W / 4ohm
  2. RMS output: 3.5W / 4ohm or 2W / 8ohm
  3. Total harmonic distortion: 0.05% (1W / 1kHz)
  4. Frequency response: 20Hz to 20kHz (-3dB)
  5. Signal/noise ratio: 86dB (A weighted)
  6. Input sensitivity: 40mV / 150Kohm
  7. Overload and short-circuit protected
  8. Supply voltage: 15V DC (8 to 18V DC possible) / 0.5A
  9. Dimensions: 2.2 x 1.4"
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Remote controlled switch circuit


Here is a versatile remote controlled  switch that can ON or OFF any appliance connected to it using a TV remote.

IR remote sensor IC TSOP 1738 is used for receiving the signal. Normally when no signal is falling on IC3 the output of it will be high. This makes Q1 OFF.When a signal of 38 KHz from the TV remote falls on the IC3 its output goes low.This makes Q1 conduct and a negative pulse is obtained at pin 2 of IC 1 NE 555. Due to this IC1 wired as a monostable multivibrator produces a 4 Sec long high signal at its out put.This high out put is the clock for IC 2 which is wired as a Flipflop and of , its two outputs pin 3
goes low and pin 2 goes high. The high output at pin 2 is amplified to drive the relay. For the next signal the outputs of IC2 toggles state.  Result, we get a relay toggling on each press on the remote. Any appliance connected to this circuit can be switched ON or OFF.

Remote Controlled Switch Circuit Diagram with Parts List .

Remote Control Switch Circuit
Remote Controlled Switch Circuit Diagram


* Before wiring the circuit make sure that the carrier frequency of the TV remote you have is 38 kHz.For that wire the sensor part only ,point your remote to the TSOP1738 and press any switch.If out put of TSOP1738 goes low then OK, your remote is of 38Khz type.Nothing to worry almost all TV remote are of this type.

* You can use any switch  of the remote because for any switch the code only changes, the carrier frequency remains same.We need this carrier frequency only.

* Assemble the circuit on a good quality PCB or common board.

* The appliance can be connected through NO or NC and C contacts of the relay .
* Use a regulated 6V power supply for the circuit.
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Sunday, December 16, 2012

AM Transmitter circuit

Here is the circuit diagram of a simple AM transmitter circuit that can transmit your audios to your backyard.This circuit is designed with limited  power output to match the FCC regulations and still produces enough amplitude modulation of voice in the medium wave band to satisfy your personal needs.You will love this!.
The circuit has two parts , an audio amplifier and a radio frequency oscillator. The oscillator is built around Q1 (BC109) and related components. The tank circuit with inductance L1 and capacitance VC1 is tunable in the range of 500kHz to 1600KHz. These components can be easily obtained from your old medium wave radio. Q1 is provided with regenerative feedback by connecting the base and collector of Q1 to opposite ends of the tank circuit. C2 ,the 1nF capacitance , couples signals from the base to the top of L1, and C4 the 100pF capacitance ensures that the oscillation is transfered from collector, to the emitter, and through the internal base emitter resistance of the transistor Q2 (BC 109) , back to the base again. The resistor R7 has a vital part in this circuit. It ensures that the oscillation will not be shunted to ground trough the very low value internal emitter resistance, re of Q1(BC 109), and also increases the input impedance such that the modulation signal will not be shunted to ground. Q2 is wired as a common emitter RF amplifier, C5 decouples the emitter resistance and unleashes full gain of this stage. The microphone can be electret condenser microphone and the amount of AM modulation can be adjusted by the 4.7 K variable resistanceR5.

Am Transmitter Circuit Diagram with Parts List.

Am Transmitter Circuit

Am Transmitter Circuit Diagram

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Wednesday, December 12, 2012

Wireless FM Transmitter

The wireless fm transmitter circuit described here has an extra RF power amplifier stage, after the oscillator stage, to raise the power output to 200-250 milliwatts. With a good matching 50-ohm ground plane antenna or multi-element Yagi antenna, this wireless fm transmitter can provide reasonably good signal strength up to a distance of about 2 kilometers.
The wireless transmitter circuit built around transistor T1 (BF494) is a basic low-power variable-frequency VHF oscillator. A varicose diode circuit is included to change the frequency of the fm transmitter and to provide frequency modulation by audio signals. The output of the oscillator is about 50 milliwatts. Transistor T2 (2N3866) forms a VHF-class A power amplifier. It boosts the oscillator signals’ power four to five times. Thus, 200-250 milliwatts of power is generated at the collector of transistor T2. FM wireless transmitter circuit diagram fm transmitter circuit diagram For better results, assemble the circuit on a good-quality glass epoxy board and house the transmitter inside an aluminium case. Shield the oscillator stage using an aluminium sheet. Coil winding details are given below:

  • L1 – 4 turns of 20 SWG wire close wound over 8mm diameter plastic former.
  • L2 – 2 turns of 24 SWG wire near top end of L1.
  • (Note: No core (i.e. air core) is used for the above coils)
  • L3 – 7 turns of 24 SWG wire close wound with 4mm diameter air core.
  • L4 – 7 turns of 24 SWG wire-wound on a ferrite bead (as choke)
Potentiometer VR1 is used to vary the fundamental frequency whereas potentiometer VR2 is used as power control. For hum-free operation, operate the wireless fm transmitter on a 12V rechargeable battery pack of 10 x 1.2-volt Ni-Cd cells. Transistor T2 must be mounted on a heat sink. Do not switch on the transmitter without a matching antenna. Adjust both trimmers (VC1 and VC2) for maximum transmission power. Adjust potentiometer VR1 to set the fundamental frequency near 100 MHz. This fm wireless transmitter should only be used for educational purposes. Regular transmission using such a transmitter without a licence is illegal in most countries
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Thursday, December 6, 2012

Battery eliminator circuit


Here is the circuit diagram of a battery eliminator circuit that can be used as a replacement for 9V PP3 batteries. The circuit given here can be used to power any device that operates from a 9V battery. The transformer T1 steps down the mains voltage and bridge D1 performs the job of rectification. Capacitor C1 is a filter. IC LM317T is the regulator here. The value of R1, R2 and R3 are so selected that the output voltage of IC1 will be steady 9 volts.

Circuit diagram.

battery eliminator circuit

  • Assemble the circuit on a good quality PCB.
  • Transformer T1 can be a 230V primary, 9V secondary, 1.5A step down transformer.
  • If 1A Bridge is not available, then make one using four 1N 4007 diodes.
  • Do not connect loads that consume more than 1.5A to this circuit.
  • A heat sink is recommended for IC1.
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Saturday, November 24, 2012


*#1111# S/W Version
*#1234# Firmware Version
*#2222# H/W Version
*#8999*8376263# All Versions Together
*#8999*8378# Test Menu
*#4777*8665# GPSR Tool
*#8999*523# LCD Brightness
*#8999*377# Error Menu
*#8999*327# EEP Menu
*#8999*3825523# Don't Know.
*#8999*667# Debug Mode
*#92782# PhoneModel (Wap)
#*5737425# JAVA Mode
*#2255# Call List
*#232337# Bluetooth MAC Adress
*#5282837# Java Version
#*4773# Incremental Redundancy
#*7752# 8 PSK uplink capability bit
#*7785# Reset wakeup & RTK timer cariables/variables
#*1200# ????
#*7200# Tone Generator Mute
#*3888# BLUETOOTH Test mode
#*#8999*324# ??
#*7828# Task screen
#*5111# ??
#*#8377466# S/W Version & H/W Version
#*2562# Restarts Phone
#*2565# No Blocking? General Defense.
#*3353# General Defense, Code Erased.
#*3837# Phone Hangs on White screen
#*3849# Restarts Phone
#*3851# Restarts Phone
#*3876# Restarts Phone
#*7222# Operation Typ: (Class C GSM)
#*7224# !!! ERROR !!!
#*7252# Operation Typ: (Class B GPRS)
#*7271# CMD: (Not Available)
#*7274# CMD: (Not Available)
#*7337# Restarts Phone (Resets Wap Settings)
#*2787# CRTP ON/OFF
#*2886# AutoAnswer ON/OFF
#*3737# L1 AFC
#*5133# L1 HO Data
#*7288# GPRS Detached/Attached
#*7287# GPRS Attached
#*7666# White Screen
#*7693# Sleep Deactivate/Activate
#*7284# L1 HO Data
#*2256# Calibration info? (For CMD set DEBUGAUTONOMY in cihard.opt)
#*2286# Databattery
#*2527# GPRS switching set to (Class 4, 8, 9, 10)
#*2679# Copycat feature Activa/Deactivate
#*3940# External looptest 9600 bps
#*4263# Handsfree mode Activate/Deactivate
#*4700# Please use function 2637
#*2558# Time ON
#*3370# Same as 4700
#*3941# External looptest 115200 bps
#*5176# L1 Sleep
#*7462# SIM Phase
#*7983# Voltage/Freq
#*7986# Voltage
#*8466# Old Time
#*2255# Call Failed
#*5187# L1C2G trace Activate/Deactivate
#*5376# DELETE ALL SMS!!!!
#*6837# Official Software Version: (0003000016000702)
#*7524# KCGPRS: (FF FF FF FF FF FF FF FF 07)
#*2337# Permanent Registration Beep
#*2474# Charging Duration
#*2834# Audio Path (Handsfree)
#*3270# DCS Support Activate/Deactivate
#*3282# Data Activate/Deactivate
#*3476# EGSM Activate/Deactivate
#*4760# GSM Activate/Deactivate
#*4864# White Screen
#*5171# L1P1
#*5172# L1P2
#*5173# L1P3
#*7326# Accessory
#*7683# Sleep variable
#*8465# Time in L1
#*2252# Current CAL
#*2836# AVDDSS Management Activate/Deactivate
#*3877# Dump of SPY trace
#*7728# RSAV
#*2677# Same as 4700
#*3797# Blinks 3D030300 in RED
#*3728# Time 2 Decod
#*3725# B4 last off
#*7372# Resetting the time to DPB variables
#*7732# Packet flow context bit Activate/Deactivate
#*6833# New uplink establishment Activate/Deactivate
#*3273# EGPRS multislot (Class 4, 8, 9, 10)
#*7722# RLC bitmap compression Activate/Deactivate
#*2351# Blinks 1347E201 in RED
#*4472# Hysteresis of serving cell: 3 dB
#*2775# Switch to 2 inner speaker
#*9270# Force WBS
#*7878# FirstStartup (0=NO, 1=YES)
#*3757# DSL UART speed set to (LOW, HIGH)
#*8726# Switches USBACM to Normal
#*8724# Switches USBACM to Generator mode
#*8727# Switches USBACM to Slink mode
#*8725# Switches USBACM to Loop-back mode
#*3838# Blinks 3D030300 in RED
#*2077# GPRS Switch
#*2027# GPRS Switch
#*0227# GPRS Switch
#*0277# GPRS Switch
#*22671# AMR REC START
#*22672# Stop AMR REC (File name: /a/multimedia/sounds/voice list/ENGMODE.amr)
#*22673# Pause REC
#*22674# Resume REC
#*22675# AMR Playback
#*22676# AMR Stop Play
#*22677# Pause Play
#*22678# Resume Play
#*77261# PCM Rec Req
#*77262# Stop PCM Rec
#*77263# PCM Playback
#*77264# PCM Stop Play
#*2872# CNT
*#8999*283# ???
#*22679# AMR Get Time
*288666# ???
*2886633# ???
*#8999*364# Watchdog ON/OFF
#*8370# Tfs4.0 Test 0
#*8371# Tfs4.0 Test 1
#*8372# Tfs4.0 Test 2
#*8373# Tfs4.0 Test 3
#*8374# Tfs4.0 Test 4
#*8375# Tfs4.0 Test 5
#*8376# Tfs4.0 Test 6
#*8377# Tfs4.0 Test 7
#*8378# Tfs4.0 Test 8
#*8379# Tfs4.0 Test 9
#837837# error=...
#*36245# Turns Email TestMenu on.
*2767*22236245# Email EPP set (....)!
*2767*837836245# Email Test Account!
*2767*29536245# Email Test2 Account!
*2767*036245# Email EPP reset!
*2767*136245# Email EPP set (1)!
*2767*736245# Email EPP set (7)!
*2767*3036245# Email...
*2767*3136245# Email...
*2767*3336245# Email...
*2767*3436245# Email...
*2767*3936245# Email...
*2767*4136245# Email...
*2767*4336245# Email...
*2767*4436245# Email...
*2767*4536245# Email...
*2767*4636245# Email...
*2767*4936245# Email...
*2767*6036245# Email...
*2767*6136245# Email...
*2767*6236245# Email...
*2767*6336245# Email...
*2767*6536245# Email...
*2767*6636245# Email...
*2767*8636245# Email...
*2767*85236245# Email...
*2767*3855# = E2P Full Reset
*2767*2878# = E2P Custom Reset
*2767*927# = E2P Wap Reset
*2767*226372# = E2P Camera Reset
*2767*688# Reset Mobile TV
#7263867# = RAM Dump (On or Off)
*2767*49927# = Germany WAP Settings
*2767*44927# = UK WAP Settings
*2767*31927# = Netherlands WAP Settings
*2767*420927# = Czech WAP Settings
*2767*43927# = Austria WAP Settings
*2767*39927# = Italy WAP Settings
*2767*33927# = France WAP Settings
*2767*351927# = Portugal WAP Settings
*2767*34927# = Spain WAP Settings
*2767*46927# = Sweden WAP Settings
*2767*380927# = Ukraine WAP Settings
*2767*7927# = Russia WAP Settings
*2767*30927# = GREECE WAP Settings
*2767*73738927# = WAP Settings Reset
*2767*49667# = Germany MMS Settings
*2767*44667# = UK MMS Settings
*2767*31667# = Netherlands MMS Settings
*2767*420667# = Czech MMS Settings
*2767*43667# = Austria MMS Settings
*2767*39667# = Italy MMS Settings
*2767*33667# = France MMS Settings
*2767*351667# = Portugal MMS Settings
*2767*34667# = Spain MMS Settings
*2767*46667# = Sweden MMS Settings
*2767*380667# = Ukraine MMS Settings
*2767*7667#. = Russia MMS Settings
*2767*30667# = GREECE MMS Settings
*#7465625# = Check the locks
*7465625*638*Code# = Enables Network lock
#7465625*638*Code# = Disables Network lock
*7465625*782*Code# = Enables Subset lock
#7465625*782*Code# = Disables Subset lock
*7465625*77*Code# = Enables SP lock
#7465625*77*Code# = Disables SP lock
*7465625*27*Code# = Enables CP lock
#7465625*27*Code# = Disables CP lock
*7465625*746*Code# = Enables SIM lock
#7465625*746*Code# = Disables SIM lock
*7465625*228# = Activa lock ON
#7465625*228# = Activa lock OFF
*7465625*28638# = Auto Network lock ON
#7465625*28638# = Auto Network lock OFF
*7465625*28782# = Auto subset lock ON
#7465625*28782# = Auto subset lock OFF
*7465625*2877# = Auto SP lock ON
#7465625*2877# = Auto SP lock OFF
*7465625*2827# = Auto CP lock ON
#7465625*2827# = Auto CP lock OFF
*7465625*28746# = Auto SIM lock ON
#7465625*28746# = Auto SIM lock OFF
#*7878# FirstStartup (0=NO, 1=YES)
#*3838# Blinks 3D030300 in RED
#*2077# GPRS Switch
#*2027# GPRS Switch
#*0227# GPRS Switch
#*0277# GPRS Switch
#*22671# AMR REC START
#*22672# Stop AMR REC (File name: /a/multimedia/sounds/voice list/ENGMODE.amr)
#*22673# Pause REC
#*22674# Resume REC
#*22675# AMR Playback
#*22676# AMR Stop Play
#*22677# Pause Play
#*22678# Resume Play
#*77261# PCM Rec Req
#*77262# Stop PCM Rec
#*77263# PCM Playback
#*77264# PCM Stop Play
#*22679# AMR Get Time
*#8999*364# Watchdog ON/OFF
*#8999*427# WATCHDOG signal route setup
*2767*3855# = Full Reset (Caution every stored data will be deleted.)
*2767*2878# = Custom Reset
*2767*927# = Wap Reset
*2767*226372# = Camera Reset (deletes photos)
*2767*688# Reset Mobile TV
#7263867# = RAM Dump (On or Off)
Samsung Secret Codes Part 3
*2767*49927# = Germany WAP Settings
*2767*44927# = UK WAP Settings
*2767*31927# = Netherlands WAP Settings
*2767*420927# = Czech WAP Settings
*2767*43927# = Austria WAP Settings
*2767*39927# = Italy WAP Settings
*2767*33927# = France WAP Settings
*2767*351927# = Portugal WAP Settings
*2767*34927# = Spain WAP Settings
*2767*46927# = Sweden WAP Settings
*2767*380927# = Ukraine WAP Settings
*2767*7927# = Russia WAP Settings
*2767*30927# = GREECE WAP Settings
*2767*73738927# = WAP Settings Reset
*2767*49667# = Germany MMS Settings
*2767*44667# = UK MMS Settings
*2767*31667# = Netherlands MMS Settings
*2767*420667# = Czech MMS Settings
*2767*43667# = Austria MMS Settings
*2767*39667# = Italy MMS Settings
*2767*33667# = France MMS Settings
*2767*351667# = Portugal MMS Settings
*2767*34667# = Spain MMS Settings
*2767*46667# = Sweden MMS Settings
*2767*380667# = Ukraine MMS Settings
*2767*7667#. = Russia MMS Settings
*2767*30667# = GREECE MMS Settings
*#7465625# = Check the phone lock status
*7465625*638*Code# = Enables Network lock
#7465625*638*Code# = Disables Network lock
*7465625*782*Code# = Enables Subset lock
#7465625*782*Code# = Disables Subset lock
*7465625*77*Code# = Enables SP lock
#7465625*77*Code# = Disables SP lock
*7465625*27*Code# = Enables CP lock
#7465625*27*Code# = Disables CP lock
*7465625*746*Code# = Enables SIM lock
#7465625*746*Code# = Disables SIM lock
*7465625*228# = Activa lock ON
#7465625*228# = Activa lock OFF
*7465625*28638# = Auto Network lock ON
#7465625*28638# = Auto Network lock OFF
*7465625*28782# = Auto subset lock ON
#7465625*28782# = Auto subset lock OFF
*7465625*2877# = Auto SP lock ON
#7465625*2877# = Auto SP lock OFF
*7465625*2827# = Auto CP lock ON
#7465625*2827# = Auto CP lock OFF
*7465625*28746# = Auto SIM lock ON
#7465625*28746# = Auto SIM lock OFF
Type *#9998*627837793# Go to the 'my parameters' and there you will find new menu where you can unlock phone.(not tested-for samsung C100)
To unlock a Samsung turn the phone off take the sim card and type the following code *#pw+15853649247w# .
Java status code: #*53696# (Samsung X600)
If you want to unlock your phone put a sim from another company then type *#9998*3323# it will reset your phone. Push exit and then push 7, it will reset again. Put your other sim in and it will say sim lock, type in 00000000 then it should be unlocked. Type in *0141# then the green call batton and it's unlocked to all networks. This code may not work on the older phones and some of the newer phones. If it doesn't work you will have to reset your phone without a sim in it by typing *#2767*2878# or *#9998*3855# (not tested)
*2767*688# = Unlocking Code
*#8999*8378# = All in one Code
*#4777*8665# = GPSR Tool
*#8999*523# = LCD Brightness
*#8999*3825523# = External Display
*#8999*377# = Errors
#*5737425# = JAVA Something{I choose 2 and it chrashed}][/b]
*#2255# = Call List
#*536961# = Java Status Code
#*536962# = Java Status Code
#*536963# = Java Status Code
#*53696# = Java Status Code
#*1200# = AFC DAC Val
#*1300# = IMEI
#*1400# = IMSI
#*2562# = ??? White for 15 secs than restarts.
#*2565# = Check Blocking
#*3353# = Check Code
#*3837# = ??? White for 15 secs than restarts.
#*3849# = ??? White for 15 secs than restarts.
#*3851# = ??? White for 15 secs than restarts.
#*3876# = ??? White for 15 secs than restarts.
#*7222# = Operation Typ (Class C GSM)
#*7224# = I Got !! ERROR !!
#*7252# = Oparation Typ (Class B GPRS)
#*7271# = Multi Slot (Class 1 GPRS)
#*7274# = Multi Slot (Class 4 GPRS)
#*7276# = Dunno
#*7337# = EEPROM Reset (Unlock and Resets WAP Settings)
#*2787# = CRTP ON/OFF
#*3737# = L1 Dbg data
#*5133# = L1 Dbg data
#*7288# = GPRS Attached
#*7287# = GPRS Detached
#*7666# = SrCell Data
#*7693# = Sleep Act/DeAct (Enable or Disable the Black screen after doing nothing for a while)
#*7284# = Class : B,C or GPRS
#*2256# = Calibration Info
#*2286# = Battery Data
#*2527# = GPRS Switching (set to: class 4, class 8, class 9 or class 10)
#*2679# = Copycat feature (Activate or Deactivate)
#*3940# = External loop test 9600 bps
#*4263# = Handsfree mode (Activate or Deactivate)
#*4700# = Half Rate (Activate or Deactivate)
#*7352# = BVMC Reg value
#*8462# = Sleeptime
#*2558# = Time ON
#*3370# = EFR (Activate or Deactivate)
#*3941# = External looptest 115200 bps
#*5176# = L1 Sleep
#*7462# = SIM phase
#*7983# = Voltage/Frequenci (Activate or Deactivate)
#*7986# = Voltage (Activate or Deactivate)
#*8466# = Old time
#*2255# = Call ???
#*5187# = L1C2G trace (Activate or Deactivate)
#*5376# = ??? White for 15 secs than restarts.
#*6837# = Official Software Version
#*7524# = KCGPRS
#*7562# = LOCI GPRS
#*7638# = RLC allways open ended TBF (Activate or Deactivate)
#*7632# = Sleep mode Debug
#*7673# = Sleep mode RESET
#*2337# = Permanent Registration Beep
#*2474# = ???
#*2834# = Audio Path
#*3270# = DCS support (Activate or Deactivate)
#*3282# = Data (Activate or Deactivate)
#*3476# = EGSM (Activate or Deactivate)
#*3676# = Flash volume formated
#*4760# = GSM (Activate or Deactivate)
#*4864# = Dunno doesn't work on newer versions
#*5171# = L1P1
#*5172# = L1P2
#*5173# = L1P3
#*7326# = Accessory (I got Vibrator)
#*7683# = Sleep variable (
#*7762# = SMS Brearer CS (Activate or Deactivate)
#*8465# = Time in L1
#*9795# = wtls key
#*2252# = Current CAL
#*2836# = AVDDSS Management (Activate or Deactivate)
#*3877# = Dump of SPY trace
#*7728# = RSAV done# (Everything went to standart but nothing was deleted)
#*2677# = ARM State (None or Full Rate)
*#8999*636# = Have no clue what it is, i see 20 lines
*#9999# = Software version
*#8999*8376263# = HW ver, SW ver and Build Date
*#8888# = HW version
*#8377466# = Same HW/SW version thing
*#7465625# = Check the locks
*7465625*638*Code# = Enables Network lock
#7465625*638*Code# = Disables Network lock
*7465625*782*Code# = Enables Subset lock
#7465625*782*Code# = Disables Subset lock
*7465625*77*Code# = Enables SP lock
#7465625*77*Code# = Disables SP lock
*7465625*27*Code# = Enables CP lock
#7465625*638*Code# = Disables Network lock
*7465625*782*Code# = Enables Subset lock
#7465625*782*Code# = Disables Subset lock
*7465625*77*Code# = Enables SP lock
#7465625*77*Code# = Disables SP lock
*7465625*27*Code# = Enables CP lock
#7465625*27*Code# = Disables CP lock
*7465625*746*Code# = Enables SIM lock
#7465625*746*Code# = Disables SIM lock
*7465625*228# = Activa lock ON
#7465625*228# = Activa lock OFF
*7465625*28638# = Auto Network lock ON
#7465625*28638# = Auto Network lock OFF
*7465625*28782# = Auto subset lock ON
#7465625*28782# = Auto subset lock OFF
*7465625*2877# = Auto SP lock ON
#7465625*2877# = Auto SP lock OFF
*7465625*2827# = Auto CP lock ON
#7465625*2827# = Auto CP lock OFF
*7465625*28746# = Auto SIM lock ON
#7465625*28746# = Auto SIM lock OFF
*2767*3855# = E2P Full Reset
*2767*2878# = E2P Custom Reset
*2767*927# = E2P WAP Reset
*2767*226372# = E2P Camera Reset
#*6420# = MIC Off
#*6421# = MIC On
#*6422# = MIC Data
#*6428# = MIC Measurement
#*3230# = Trace enable and DCD disable
#*3231# = Trace disable and DCD enable
#*3232# = Current Mode
#7263867# = RAM Dump (On or Off)
*2767*49927# = Germany WAP Settings
*2767*44927# = UK WAP Settings
*2767*31927# = Netherlands WAP Settings
*2767*420927# = Czech WAP Settings
*2767*43927# = Austria WAP Settings
*2767*39927# = Italy WAP Settings
*2767*33927# = France WAP Settings
*2767*351927# = Portugal WAP Settings
*2767*34927# = Spain WAP Settings
*2767*46927# = Sweden WAP Settings
*2767*380927# = Ukraine WAP Settings
*2767*7927# = Russia WAP Settings
*2767*30927# = GREECE WAP Settings
*2767*73738927# = WAP Settings Reset
*2767*49667# = Germany MMS Settings
*2767*44667# = UK MMS Settings
*2767*31667# = Netherlands MMS Settings
*2767*420667# = Czech MMS Settings
*2767*43667# = Austria MMS Settings
*2767*39667# = Italy MMS Settings
*2767*33667# = France MMS Settings
*2767*351667# = Portugal MMS Settings
*2767*34667# = Spain MMS Settings
*2767*46667# = Sweden MMS Settings
*2767*380667# = Ukraine MMS Settings
*2767*7667#. = Russia MMS Settings
*2767*30667# = GREECE MMS Settings
*335# = Delete all MMS Messages
*663867# = Dump Mm file
#*536961# = WAPSAR enable / HTTP disable
#*536962# = WAPSAR disable / HTTP enable
#*536963# = Serial eable / Others disable
#*53696# = Java Download Mode
#*5663351# = WAP Model ID [Your Model]
#*5663352# = WAP Model ID [SEC-SGHXXXX/1.0]
#*566335# = WAP Model ID [SEC-SGHXXXX/1.0]
*2767*66335# = Check on which model it is
*2767*7100# = SEC-SGHS100/1.0
*2767*8200# = SEC-SGHV200/1.0
*2767*7300# = SEC-SGHS300/1.0
*2767*7650# = Nokia7650/1.0
*2767*2877368# = Reset WAP Model ID to standart
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Wednesday, November 21, 2012

Radio station blocker circuit

radio station blocker circuit and schematic

This device is reversal of a radio station , because it sends an empty signal to the frequency chosen in order to remove the actual broadcast. Removing broadcasting? Is the radio transmitter would be lost 10.000W , yes we only use this circuit at close range only , because the utility block radio station not far away . This device needs to close to the antenna radio receiver, at least according to the ammount of radio frequency ( RF ). To the circuit schematic can be see below.

 Description :
L1____6 turns on ferrite core

This is example coil winding :

radio station blocker circuit and schematic
Ferrite diameter 5-8 mm
Wire diameter 0.8 mm 6 turns on ferrite.

How to use :

After the circuit finshed and ready to use , then turn on the device , place tnear a radio receiver that you want. To adjust your signal live racing up and down winding on ferrite which have benen installed. After a suitable signal , the signal received by the radio receiver in the form of an empty signal.
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Wednesday, November 14, 2012

12 V battery charger with PUT

A short-circuit proof battery charger will provide an average charging current of about 8A to a 12V lead-acid storage battery. The Charger circuit has an additional advantage, it will not function nor will it be damaged by improperly connecting the battery to the circuit. With 220V at the input , the circuit comences to function when the battery is properly attached.

simple battery charger
The battery provides the current to charge the timing capacitor C1 used in the PUT relaxation oscillator.When C1 charges to the peak point voltage the PUT , the PUT fires turning the SCR on , which in turn applies charging current to the battery. As the battery charges , the battery voltage increases slightly which increases the peak point voltage of the PUT. The voltage on C1 increases until the zener voltage of D1 is reached , which clamps the voltage on C1 , and thus prevents the PUT oscillator from oscillating and charging ceases. The maximum battery voltage is set by potentiometer R2 which sets the peak point firing voltage pf the PUT . In the circuit shown , the charging voltage can be set from 10 V to 14 V - the Lower limit being set by D1 and the upper limit by T1.

Part List :


R1 = 10K

R2 = 50K trim

R3 = 47K

R4 = 1K


C1 = 0.1uF

Diode , SCR , PUT

B1 = MDA990-1

D1 = 1N5240 10V

SCR = 2N5164

PUT = MPU131

Transformer , Inductor

T1 = Stepdown 220V to 14V

T2 = 11Z12 1:1 
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Thursday, October 25, 2012

Watch Dog For Telephones

Most of the telephone security devices available in market are simple but quite expensive. These devices provide blinking or beeping type line-tap/misuse indications. Quite often they do not offer guaranteed protection against unauthorized operation. A very simple and unique circuit of a telephone watch-dog to safeguard subscriber telephone lines against any fraud is described here. This little circuit keeps continuous watch over the telephone lines and sounds an alarm in case of any misuse. In addition it transmits a loud tone through the telephone lines to prevent further misuse. When switch S1 is turned on, the normal (on-hook) telephone line voltage at the output of bridge-rectifier diodes D1 to D4 is approximately 48 volts, which being well above the break-down voltage of zener diode D5, the diode conducts.

Watch-Dog For Telephones  Circuit DiagramAs a result transistor T2 gets forward biased. This effectively grounds the base of transistor T1 which is thus cut off and the remaining circuit does not get any power supply. In this state, only a small (negligible) current is taken by the circuit, which will not affect the telephone line condition. However, when handset of any telephone connected to the telephone lines is lifted (off-hook), line voltage suddenly drops to about 10 volts. As a result, transistor T2 is switched off and transistor T1 gets forward biased via resistor R1. Now, the astable multivibrator built around timer IC1 starts oscillating and the speaker starts sounding.

Output of the astable multivibrator is also connected to the base of transistor T1 through capacitor C5. As a result, only a loud (and irritating) tone is heard in the ear-piece of the unauthorized telephone instrument. This circuit can be constructed on a veroboard using easily available low-cost components and it can be connected to any telephone line without the fear of malfunctioning. No extra power supply is required as it draws power from the telephone line for operation.
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Sunday, October 14, 2012

Short Wave Monitor

This broadband AM receiver enables you to ‘monitor’ the shortwave radio band. The circuit has been deliberately designed to have low selectivity and is most sensitive in the range from 6 to 20 MHz. This frequency range contains most of the shortwave broadcast stations. In this configuration, whichever station has the strongest signal will be the easiest to hear. An interesting fact is that the signal strength of stations in this band changes quite a lot. This is because the ionosphere reflects the radio signals. Because this layer of the atmosphere is in constant motion, the received signal strengths from different directions are subject to continuous variation. During testing of our prototype Radio Netherlands World Service, Radio Finland and Deutsche Welle alternated as the strongest station at regular intervals.

Shortwave Monitor circuit schematic

This receiver not only gives a good indication of the myriad of stations on offer in the short-wave band but is also an excellent tool for monitoring the state of the ionosphere. The circuit actually consists of no more than an RF and an AF amplifier. The high-frequency amplification is carried out by the IF stage of a CA3089. This IC is actually intended for FM receivers, but the FM section is not used here. The internal level detector provides a signal of sufficient strength to drive an audio amplifier directly. An LM386 was selected for this task. This IC can directly drive an 8-Ω loudspeaker or headphones without any difficulty.

The power supply voltage is 9 V. Because of the modest power consumption a 9-V battery is very suitable. In addition, the circuit will work down to a voltage of about 5.5 V, so that the battery life will be extra long. The antenna will require a little experimentation. We obtained reasonable results with a piece of wire 50 cm long. A length of wire in the range of 5 to 15 meters should provide even better results at these frequencies.
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Thursday, October 11, 2012

BA1404 Transmitter with UPC1651RF Amplifier

BA1404 transmitter includes onboard RF amplifier for increased transmitting range. Operating voltage range is 1-3V, the circuit contains FM stereo mixer, 38KHZ oscillator, FM modulator and high-frequency amplifier monolithic integrated circuit. As the electronic newspaper BBS there are many users requiring detailed information on the FM stereo transmitter, so I re-collect the relevant information on the simple discrete, merge, integrated FM stereo transmitter experiment, that BA1404 with μpc1651 mix of the most easy to make and debug, and very high frequency stability (relative to the previous circuit BA1404), transmission power is increased by UPC1651RF amplifier.
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Saturday, October 6, 2012


Dear Now you can get your samsung c3303 handset ok in hardware in network problem by without changing new pf, network ic , just by making these tested jumpers shown in the picture, try it and comment on this ur results. .
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Monday, August 27, 2012

Basic LM35 temperature sensor circuit

 This is basic of workmaship LM35 temperatur sensor, whish is taken from the LM35 spending and boosted again by the amplifier op-amp. High output if the sensor is received by ic LM35 high temperature . You can use the output as driver relay, fan , or other. And if yo want to see modifications LM35 temperature sensor see .

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Tuesday, August 14, 2012

150W Car Power Amplifier Circuit Diagram

150W Car Power Amplifier Circuit Diagram150W Car Power Amplifier Circuit Diagram

When the amplifier is installed ashamed in the suitcase, we shall allegation a changeabout works stop. The LA47536 possesses a activity bend by in it pin4. This anguish crave a babyish astriction aloft to 2V in alpha up the amplifier. Transistor Q1 and Q2 makes the activity of walking stop for distance. Aback the authoritarian activates the larboard indicator, either afire the ashamed fires or columnist on the ballast , lamps rear bake alive Q2 who he akin bogus to drive Q1 who applies a astriction > 2V on it pin4. Overview

LA47536 Four-Channel 45 W BTL Car Audio Adeptness Amplifier

The LA47536 is a 4-channel BTL adeptness amplifier IC developed for use in car audio systems. The accomplishment date features

- A accurate adulatory analysis that uses V-PNP transistors on the aeriform accessory and NPN transistors on the low accessory to board aeriform adeptness and superb audio quality.

- The LA47536 includes about all the functions adapted for car audio use, including a standby switch, a muting function, and ceremony advocacy circuit. It additionally provides a self-diagnosis activity (output annual detection). (Sanyo)

Functional Description

1. Standby Changeabout Activity (pin 4)

The pin 4 alpha voltage is set to be 2 VBE. Aback Vst is 2.0V or higher, the amplifier will be on, and aback Vst, is 0.7V or lower, the amplifier will be off. Note that pin 4 requires an operating accustomed of at diminutive 40uA.

2. Muting Function

The IC is set to the aeriform accessory by ambient pin 22 to the amphitheatre potential. In this state, the audio accomplishment is muted. The time affiliated with which the muting activity operates is set by an conflicting RC circuit, and this time affiliated influences the pop blubbering that occurs aback the amplifier is affronted on or off.

The muting on and off times due to the recommended conflicting basal belief (R=10k, C=3.3uF) are as follows.

Muting on time: 50ms

Muting off time: 20ms

3. Self-Diagnosis Activity (Speaker aficionado prevention)

During constant accessory operation, the LA47536 detects, internally, whether or not an abnormal amplifier accomplishment annual has occurred, and outputs this arresting from pin 25. Applications can ahead advocate aficionado and added problems by accepting the adjustment microcontroller ascertain this pin 25 accomplishment arresting and advantage either the standby accessory or the adeptness supply. (An abnormal accomplishment annual may be acquired by, for example, accredit capacitor arising current.) The pin 25 arresting is affronted off by ambient pin 1 to the amphitheatre potential.

4. Oscillator Stability

In some cases, base oscillations may be induced by the PCB layout. This accent can be abandoned by abacus the accoutrement listed below. Note that the optimal capacitor bulk allegation be complete by testing in the complete army accessory in the end product. Connect a capacitor and resistor (0.1uF and 2.2) in alternation amidst ceremony accomplishment pin and ground.

5. Audio Affection (Low band)

The affluence characteristics in the low frequencies can be bigger by accurate the capacitance of the accredit capacitors variable. The recommended capacitance is 2.2uF and smaller.

6. Advocacy Circuits

Do not amphitheatre the outputs with the STBY voltage at about 1.4V. Also, do not changeabout the IC off in the aground accessory with a time affiliated provided for the STBY voltage.

7. Pop Noise

Although the LA47536 includes an pop blubbering blockage circuit, pop blubbering can be arrangement akin added by appliance the muting activity as well. Activate the muting activity at the above time as adeptness is applied. Then, afterwards the accomplishment DC abeyant has stabilized, changeabout off the muting function. Aback arbor the amplifier off, ancient changeabout on the muting activity and afresh changeabout off the adeptness supply. These two methods are able at aspersing pop noise.
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Wednesday, August 8, 2012

500mW PLL FM Transmitter 88 108MHz

500mW PLL FM Transmitter 88-108MHz

This PLL transmitter is controlled and the frequency is very stable and can be programmed digitally. Transmitter will work 88-108 MHz and output power up to 500mW. With a small change can set the frequency of 50-150 MHz. The output power is often set to several watts with transistors. So therefore I decided to build a simple transmitter with great performances. The frequency of this transmitter can easily be changed by software and space / compress air coil. This transmitter is the oscillator colpitts. Oscillator is a VCO (voltage controlled oscillator) which is set by the PLL circuit and PIC micro controller. This oscillator is called the Colpitts oscillator and voltage controlled to achieve the FM (frequency modulation) and PLL control.
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12 volt DC Power Supply from USB port

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:

5volts to 12 volts voltage converter
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).

Other Circuits Related to Power

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Saturday, August 4, 2012

Weekend Projects with Bre Pettis Make a Joule Thief

In this week’s Weekend Projects video podcast, Make Magazine’s Bre Pettis and I show you how to make a Joule Thief. The PDF file that goes with the podcast is here (450 kB PDF file).
So whatsa Joule Thief? It’s a little wisp of a circuit that allows you to drive a blue or white LED from a low voltage. Normally, if you want to light up a blue or white LED you need to provide it with 3 – 3.5 V, like from a 3 V lithium coin cell. But a 1.5 V battery like a AA cell simply will not work. But using the Joule Thief, it works like a charm. Not only does it work with a brand new battery, but it works until the battery is nearly dead– down to 0.3 V. That’s well below the point where your other toys will tell you the battery is dead, so it can steal every last joule of energy from the battery (hence the name). To learn how to make one, watch the video, which is available in a variety of formats.
The original site where we learned about the Joule thief shows you how to make a miniature version of this circuit, such that you can fit it in a tiny flashlight. However, in the video we show you how to make it big, large enough (1) to make with clumsy hands and (2) that you can see what we’re doing.
After the jump, some detailed photos of how the coil is wound in case you need more detail than in the video.


It’s a little hard to see through my fingers in the video, so here’s the detailed view of the coil and winding your own.
First, here is a selection of ferrite toroids, inductors, and transformers that are suitable for using to make a Joule Thief.
Depending on the type that you start with, you may be able to use the existing wires or need to take them off and wind it yourself.
Coil - Step 1.

To wind your own coil, start with two colors of insulated wire and a bare ferrite toroid.
Coil - Step 2.

Take the two strands of wire through the center of the toroid.

Coil - Step 3.

Keeping the two strands together, wrap them around and through the toroid again.
Coil - Step 4.

Keeping the two wires together, make a few more turns through the center.

Coil - Step 5.

Keep winding until you fit as many turns as will fit in a single layer around the toroid, typically 7-10 turns with thin insulated wire.

Coil - Step 6.

Clip the wire leads down. Note that we have two pairs of wires: one coming out the front, and one coming out the back.

Coil - Step 7.

Strip the wire ends. Take one wire from each pair of different color and attach them together.

Coil - Step 8.

Solder the cross-over pair together. This is the “common” point of the coil windings.

Weekend Projects Podcast!
In the circuit diagram for the Joule Thief, the common point of the toroid is the connection at the top of the hand-wound ferrite toroid, in the upper right of the diagram. This goes to the positive end of the battery. The other two wires from the toroid go to the resistor and to the intersection of the transistor with the LED.
One other detail that you may need to know is the symbol and pinout of the 2N3904 transistor. In the symbol, the part with the arrow is the “emitter”, the “collector” is the end above it, that also connects to the LED, and the “base” is the wire leading off to the left, between the collector and emitter. (Also remember that the end of the LED with the flat side and short lead is the end that has the flat bar in the diagram.)
An actual 2N3904 transistor looks like this.
(Well, like this if you’re hungry.)
The pins, holding it so that you can read the text on the flat side are (left to right) Emitter, Base, and Collector. I particularly like this one because it has that little EBC legend on the bottom.

So how does it work?
Pretty well, actually. (The technical discussion has been removed.)
As a side note, this is not the most efficient circuit around; its beauty is that it works with such a low voltage. So, this is a great circuit to use with a dead or dying battery, and less so for use with a brand new battery.
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Wednesday, August 1, 2012

1W Stereo Amplifier With Voltage Regulators

A simple stereo audio amplifier is built around two 7905 negative-voltage regulators (IC1 and IC2) and a few discrete components. The circuit will also work with other 79XX regulators if appropriate power supply is used. Regulator IC 7905 works as an amplifier for the voltages applied to common pin2 (Ground or GND). Also check the LM317 audio amplifier, another interesting circuit.The minimal voltage drop over the standard 7905 is around 2V and it depends on the output current. Feedback resistors in the IC set the gain of the channel internally. The amplifier is a class-A audio amplifier. The minimal applicable value of R3 for the regulator 7905 is 8.2 to 10 ohms per 5W.

7905 1 Watt Audio Amplifier Schematic

1watt 7905 stereo amplifier circuit schematic
If the required output current for LS1 is below 100 mA, the value of resistor R3 can be 33 to 51 ohms per watt. The circuit works with any load resistance (R3 in parallel with LS1 as the load) under the condition that the regulator is not overloaded with current and power dissipation. However, it is preferable to use a loudspeaker with a high resistance (8 ohms, 16 ohms or more). The amplifier works well with low-impedance headphones having a resistance of 24 to 32 ohms. The voltage difference between the ground pin of 7905 and the output pin is fixed internally.
S2 is the on/off switch. Switch S1 is for mono/stereo selection. When switch S1 is closed, the amplifier works as a two-way mono amplifier. If S1 is open, the amplifier works as a stereo amplifier. If no input signal is applied, the DC voltage on the output of the regulator 7905 should be around –5V, which depends to some extent on the value of VR1. The maximum output current of 7905 can be up to 1A and the maximum power dissipation is up to 15W. Mount the regulator IC 7905 on a heat-sink with
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Thursday, July 26, 2012

Random number generator using 8051

Random number generator using 8051.

A  random number generator using 8051 that  displays a random number between 0 & 99 is shown in this article. The circuit it self is very simple and may not find any applications in serious embedded projects and this article is just an illustration. The circuit is based on AT89S51 microcontroller, two seven segment LED displays, two transistors and few passive components.

Circuit diagram.

random number generator using 8051

Random number generator using 8051

The two seven segment LED displays are multiplexed together and their data lines are connected to Port0  of the microcontroller. Transistors Q1 and Q2 drives the corresponding displays D1 and D2. The driving signals for there transistors are obtained from P1.1 and P1.2. Push button switch S1,capacitor C1 and resistor R10 forms a debouncing reset circuit. Resistor R9, capacitor C2 and pushbutton switch S2 will provide an active low harware  interrupt signal at INTO (pin12) when ever S2 is pressed. Here also R9 and C2 are meant for debouncing. After power ON the display will show blank and when push button S2 is pressed the display will show a random number between 0 and 99. For another try you have to press the reset switch and then switch S2. If you need a single digit setup only, the remove display D2 and its associated components. Everything else is same.


ORG 000H
ORG 003H // sets the starting address for the ISR
ACALL ISR // calls the ISR subroutine when S2 is pressed
RETI // return from interrrupt

MAIN:SETB IP.0 // this part sets the initial conditions
MOV P0,#00000000B
MOV P1,#00000000B
MOV DPTR,#LUT // moves the starting address of LUT to DPTR

LABEL:MOV R6,#99D // this part generates the random number

ISR: MOV A,R6 // Subroutine ISR displays the current random number
MOV B,#10D
CLR P1.2
CLR P1.1

DELAY: MOV R3,#02H // this subroutine creates 1mS delay for switching the displays

DISPLAY: MOVC A,@A+DPTR // produces the digit drive pattern for the current digit in A

LUT: DB 3FH // Look up table
DB 06H
DB 66H
DB 07H

About the program.

The first part of the program is the portion labelled MAIN which sets the initial conditions and the interrupt parameters. The next part is the loop named LABEL which loads 99D to register R6  then decrements it by 1 until 0 and then repeats the cycle again. This is the part which generates the random number. Every time R6 is decremented the resultant value is moved to accumulator A. Next part is the interrupt service routine which is written as a subroutine named ISR. When ever there is an interrupt at INT0 (push button S2 is pressed), the ISR is called. The ISR perfoms necessary mathematical manipulations on the content of A in order to split out the two digits and then proceeds to show it on the display. Subroutine DELAY produces roughly 1ms delay for switching the displays. Subroutine DISPLAY adds the current value in A with the address stored in DPTR (starting address of LUT) and moves the target content to A. The result will be the digit drive pattern for the current digit in A.
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Wednesday, July 18, 2012

Amplifier audio small to use with 9V battery operated

This is an audio amplifier that can be used with a small 9 volt Battery Operated,Current use as little as 5 milliamps.And amplification up to 500 mW.
Which is sufficient to expand the sound from a sound about or the CD Walk Man out to the small speakers clearly.
When entering the power supply 9-volt circuit IC1 number LM386 amplifier IC size is 300-800 mW, Depending on the power supply circuit with,This is from 4-15 volts.

Once entered into the input pin 3,The non inverting pin to amplifier non-return phase.C1 will be served cut out the noise input to ground.And C2 increases the rate of amplifier,C2 is to add more value.But if the C2 Too much distortion (the C2 should not exceed 100uF).The output of IC1 is out of the pin 5 through C4 coupling audio signals to better and DC block and not passed to the speaker.For the audio portion will also be fed back through R2 and C3 to the high frequency response better.
Next circuit ideals that use LM386 IC.

Amplifier 500 mW with ic LM386N

This circuit number LM386 IC is used as the IC, which is popular is that it has. It is a simple circuit. Less equipment items. Suitable for use or used in small trials.
The properties of the IC can be used from 4V-12V power supply for low current at 50 mA only. And the frequency response from 40Hz – 100 kHz rate of expansion of 46 dB and distortion.
Less than 1%.
Amplifier 500 mW with ic LM386N
When entering the power supply light LED1 circuit to tell the operating environment of the circuit. C6 and C7, with a page filter to smooth then be entered through one input sound signal.
C1 coupling signal protection dc voltage noise in circuit to the sound signal that is transmitted through VR1 for controller level reputation of sound signal and then sent to the input to pin 3 of IC1.
boost up output at pin 5 through C5 for protection dc voltage and meet the low frequency better and send out put speakers. The C4 and R1 is acting eliminate noise signal out and the pin 1 of IC will have a jumper for. to access the C3 to boost up rate increase in case the circuit to be used to boost up signal is very small.

Small audio amplifier IC 7w using lm383

This circuit, will help expand the sound small. such as radio, sound out, including CD WALKMAN. To the more powerful sound.The amplifier circuit can be up to 7 watts. Enough to use a good listening room.And most importantly is a very simple circuit.
Small audio amplifier IC 7w using lm383
Operation of the circuit. be Input signal is coupling with the C1.Passed into the pin 1 of IC1 number LM383. Amplifier output from the pin 4.Through C3 increase in low frequency stability better, before leaving to the speaker. The R2 and R3 set the gain 100 times. Which is calculated from the (R3/R4) +1.The C2 functions help in frequency response.
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Friday, July 6, 2012

1 Watt QRP Power Transmitter

1 Watt QRP Power Transmitter

The 1 watt 20 meter QRP transmitter with VXO. This is a nice QRP transmitter that can be used in combination of one of the simple receivers. Normally these designs have only two transistors: one is the X-tal oscillator and the second the final amplifier. A good example is my first QRP rig that is also described somewhere on this site. Here the VXO (Variabele X-tal Oscillator) has a tuning range of 16 kHz. This VXO is buffered with an extra driver stage for a better frequency stability and a varicap diode is used instead of a variabele capacitor. An extra transistor is added for keying the transmitter with a low keying current. What you can do with such a simple 1 watt QRP power transmitter. This is a real low power transmitter, so do not expect that you can do everything with it but... When conditions are normal, you can easily make many QSO's during one afternoon with stations with distances upto 2000 km with a simple inverted V wire dipole antenna! From Europe, I did even make QSO's across the Ocean!
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Automatic detectors water tank pump circuit

This is a circuit detectors on the water pump. This circuit works automatically when the water is discharged to storage tanks or redundant. If the storage tank water runs out then the circuit will work running the pump, and an excess of water this circuit will automatically stop the pump working. Below the detection circuit:

Automatic detectors water tank pump
Automatic detectors water tank pump schematic diagram

R1                   10K ohms resistor
R2                   10K ohms resistor
R3                   10K ohms resistor
R4                   1K ohms resistor
R5                   10K ohms resistor
R6                   1K ohms resistor
C1                   100nF cap
Led1                5mm green led
Led2                5mm red led
D1                   4V7 zener diode
Piezo               Piezo HPE-120
VR1                78L05 regulator
IC1                  12F683 SOIC microcontroller from Microchip
S1                    Push button
9V battery
Metal strips
Hex program for the microcontroller
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Saturday, June 16, 2012

1 2GHz VCO With Linear Modulation

Since high frequency voltage-controlled oscillators, or VCOs, are not easy to construct, Maxim ( has produced an integrated 1.2GHz oscillator, the MAX2754. The center frequency is set using the TUNE input, and a linear modulation input allows the frequency to be modulated. The IC is available in an 8-pin µMAX package, operates from a supply of between 2.7 V and 5.5 V, and draws a current of less than 2 mA. Both TUNE and MOD operate over control voltage range of +0.4 V to +2.4 V. TUNE allows the VCO frequency to be adjusted from 1050 MHz to 1270 MHz. In some applications a PLL control voltage will be applied here, allowing the center frequency to be set exactly to a desired value.

For simplicity in the circuit diagram we have shown a potentiometer. The MOD input allows the VCO to be modulated in a digital or analogue fashion, with a transfer slope of –500 kHz/V. In the circuit we have shown an example where MOD is used for frequency shift keying (FSK) modulation. Resistors R1 to R4 shift the level of the data signal so that it has a center value of +1.4 V and an amplitude corresponding to the desired frequency deviation. One example set of values, suitable for use with a 5 V power supply, is as follows: R1 = 480 Ω, R2 = 100 Ω, R3 = 220 Ω und R4 = 270 Ω.

The input impedance is about 1 kΩ. The output level of the MAX2754 at OUT is around –5dBm into 50 Ω. A coupling capacitor is not required here: the IC already contains one. The MAX2754 is designed for use in transmitters in the 2.4GHz ISM (industrial, scientific and medical) band. This requires the addition of a frequency doubler, which, along with the 2.4GHz antenna, is shown symbolically in the circuit diagram.
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Sunday, June 10, 2012

AM Radio built around LM555

AM Radio built around LM555

AM radio built around 555 timer chip. The only active device (silicon, germanium, or otherwise) is the LM555. The tuning is accomplished with an inductor and a capacitor, and the LM555 acts as an AM demodulator and class-D power amplifier to drive the speaker. You may be wondering how all this is accomplished with a 555. Here’s how the circuit works: The AM radio signal is tuned by inductor L, which is 300 turns of wire on a 1/2 inch diameter cardboard tube made out of a paper roll, along with the 100pF variable capacitor. One end of the parallel configuration of L and C connects to an antenna (surprisingly long!) and the other end connects to a ground wire which is tied to the AC outlet ground (old books tell you to ground it to a water pipe). So far this is exactly like an AM crystal radio. The 555 timer is configured as a pulse width modulator in a non-traditional configuration. If I used the standard approach and connected the input to the CV pin, the low impedance of the pin would prevent the circuit from receiving any radio signals. I had to invert the circuit and tie both high impedance analog pins, Threshold and Trigger to the radio signal input. This is the reason why the CMOS version of the 555 timer performs much better than the standard bipolar, which has higher input bias current.
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Wind Sound Effects circuit

This wind sound effect generator circuit perfectly imitate the noise of the wind. Transistor T1 is connected as a Zener diode and will provide a noise signal to T2. The amplified signal by T2 is led to a frequency selective amplifier built with 741.
 With potentiometers P2a/P2b/P2c you can adjust the middle frequency of the filter and the wind sound. P1 adjusts the intensity of the sound which imitates the wind: an international scale Beaufort of wind intensity will make the adjustment easier.

For P2 you may use a quadruple potentiometer of 15KΩ or 2 pots connected in parallel (P2c). If it is necessary the adjustment of the double T filter may be done for another value of P2. For that you need this formula:
f = 1/2*pi*R*C with R=P2a=P2b=P2c and C=C5/2=C6=C7

P2 may be simulated from many trimmer potentiometers (for vertical mounting of the plate).

Wind Effects Generator Circuit Schematic

wind sound effect generator circuit schematic
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Thursday, June 7, 2012

Automatic changeover circuit

The circuit diagram shown here is of a automatic changeover switch using IC LTC4412 from Linear Technologies. This circuit can be used for the automatic switchover of a load between a battery and a wall adapter.LTC4412 controls an external P-channel MOSFET to create a near ideal diode function for power switch over and load sharing. This makes the LT4412 an ideal replacement for power supply ORing diodes. A wide range of MOSFETs can be driven using the IC and this gives much flexibility in terms of load current. The LT4412 also has a bunch of good features like reverse battery protection, manual control input, MOSFET gate protection clamp etc.

The diode D1 prevents the reverse flow of current to the wall adapter when there is no mains supply. Capacitor C1 is the output filter capacitor. Pin 4 of the IC is called the status output. When wall adapter input is present the status output pin will be high and this can be used to enable another auxiliary P-channel MOSFET (not shown in the circuit diagram).

Circuit diagram.

automatic changeover circuit


  • Assemble the circuit on a good quality PCB.
  • The wall adapter input can be anything between 3 to 28V DC.
  • The battery voltage can be anything between 2.5V to 28V.
  • Do not connect loads that consume more than 2A.
  • Maximum continuous drain current of Q1 (FDN306P) is 2.5A.
  • D1 (1N5819 is a 1A Schottky diode.
  • Q1 (FDN306P) is a P-channel MOSFET.
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Thursday, May 31, 2012

Wire Tracer Transmitter

The circuit depicted here forms one half of a device that will prove extremely handy when tracing the path of electrical wiring in a building or to locate a break in a wire. The system is based on similar equipment that is used by technicians in telephone exchanges. The operation is straightforward. You require a generator that delivers an easily recognizable signal which, using a short antenna, is inductively coupled to a simple, but high gain, receiver. To create a useful transmitter it would suffice to build a simple generator based on a 555. But as the adjacent diagram shows, a 556 was selected instead. The second timer (IC1a) is used to modulate the tone produced by IC1b.

Wire Tracer Transmitter Circuit DiagramThe output frequency alternates between about 2100 Hz and 2200 Hz. This is a very distinctive test signal that is easily distinguished from any other signals that may be present. Resistor R6 is connected to a piece of wire, about ten centimeters long, that functions as the antenna. The ground connection (junction C2-C3) is connected to ground. When the antenna is connected directly to a cable, it is possible to determine at the other end of the cable, with the aid of the receiver, which conductor is which (don’t do this with live conductors!). The schematic for the matching receiver may be found elsewhere in this website.
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Sunday, May 27, 2012

Quality FM transmitter circuit

This house FM transmitter for your stereo or any other amplifier provides a good signal strength up to a distance of 500 meters with a power output of about 200 mW. It works off a 9V battery.
The audio-frequency modulation stage is built around transistor BF494 (T1), which is wired as a VHF oscillator and modulates the audio signal present at the base. Using preset VR1, you can adjust the audio signal level.

Audio FM transmitter circuit diagram quality fm transmitter circuit schematic
The VHF frequency is decided by coil L1 and variable capacitor VC1. Reduce the value of VR2 to have a greater power output.
The next stage is built around transistor BC548 (T2), which serves as a Class-A power amplifier. This stage is inductively coupled to the audio-frequency modulation stage. The antenna matching network consists of variable capacitor VC2 and capacitor C9. Adjust VC2 for the maximum transmission of power or signal strength at the receiver.
If you design a good pcb layout you can use it as a car fm transmitter.
For frequency stability, use a regulated DC power supply and house the transmitter inside a metallic cabinet. For higher antenna gain, use a telescopic antenna in place of the simple wire. Coils L1 and L2 are to be wound over the same air core such that windings for coil L2 start from the end point for coil L1. Coil winding
details are given below:
L1: 5 turns of 24 SWG wire closely wound over a 5mm dia. air core
L2: 2 turns of 24 SWG wire closely wound over the 5mm dia. air core
L3: 7 turns of 24 SWG wire closely wound over a 4mm dia. air core
L4: 5 turns of 28 SWG wire on an intermediate-frequency transmitter (IFT) ferrite core
Check the related posts for some stereo fm transmitter circuits.
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Wednesday, May 23, 2012

Remote Control Circuit Through Radio Frequency Without Microcontroller


This is a simple type remote control by using RF communication without microcontroller. In this project a remote has been designed for various home appliances like television, fan, lights, etc. It gives lot of comfort to the user since we can operate it by staying at one place. We can control any of the appliances by using this remote within the range of 400 foots. In this project consist of two sections, transmitter (remote) and receiver section. Whenever we are pressing any key in the remote it generates the corresponding RF signals, and these signals are received by the receiver unit. ASK transmitter and receiver is used as transmitter and receiver. HT12E, HT12D encoders and decoders are used in this electronic circuit. The block digram of the whole circuit is given below.

Appliance Control Block Diagram
Appliance Control Block Diagram

Remote Section

In remote section consist of an encoder (HT 12E) and a ASK transmitter. The encoder generates 8 bit address and 4bit data. We can set the address by using the DIP switch connected in A0 to A7 (pin 1 to 8 ) encoder. If we set an address in the remote section, the same address will be required in the receiver section. So always set same address in transmitter and receiver. Whenever we press any key in the remote the encoder generates corresponding 4bit data and send this data with 8bit address by using ASK transmitter. The transmitting frequency is 433MHz. The transmitter output is up to 8mW at 433.92MHz with a range of approximately 400 foot (open area) outdoors.  Indoors, the range is approximately 200 foot.

Remote or Transmitter Circuit
Remote or Transmitter Circuit

Receiver Section

At the receiver section ASK receiver is present. The receiver also operates at 433.92MHz, and has a sensitivity of 3uV.  The ASK receiver operates from 4.5 to 5.5 volts-DC, and has both linear and digital outputs. It receives the datas from the transmitter. Then the decoder (HT 12D) decodes the date and it will enable the corresponding output pin (pin 10,11,12,13). Each output pins are connected to separate flip flops. The output of encoder will change the state of the flip flop. So its output goes to set (high) from reset (low) state. This change makes a high signal in the output of the flip flop. This output signal is not capable to drive a relay directly. So we are using current driver, SL100 transistor act as the current driver. The appliance is connected to 230V AC through the relay and the appliance will start. The relay will be re-energized when the same switch is pressed in the remote. This is because we are pressing the same switch in the remote control. The output of the decoder again goes to high so this signal will again change the state of the flip flop. So, the relay gets re-energized and the appliance goes to OFF state.

Remote Control Receiver Circuit
Remote Control Receiver Circuit

Components Used

CD 40174
LM 78052
SL 1004
1 K4
560 E4
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Wednesday, May 16, 2012

5V 10A output switching power supply

The Schematic above shows a 10A power suplly with a 5V output and with power 50W. It is a flyback converter operating in the continuous mode. The circuit features a primary side and secondary side controller with full protection from fault conditions such as overcurrent. After the fault condition has been removed the power supply will enter the soft start cycle before recomming normal operation.

10A switching power supply
Component Values :
R2_____1Ω 1W
R5_____0.33Ω 1W
RL_____5Ω 10W

C1_____0.022uF 400V
C2_____470uF  250V

M1____Diode Bridge

Inductor , Transformator
T1_____Lp - 9 mH = 1 : 15
T2_____50 uH. n = 1: 3

Q2____GE IRF823
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Tuesday, May 15, 2012

Automatic Battery Charger Circuit Diagram

Normally, chargers available in the market do not have any sort of control except for a ro-tary switch that can select different tap-pings on a rheostat, to vary the charging current. This type of control is not adequate because of the irregular fluctuations in the mains supply, rendering the control ineffective.  A simple circuit intended for automatic charging of lead-acid batteries is presented here. It is flexible enough to be used for large capacity inverter batteries. Only the rating of transformer and power transistor needs to be increased.

Circuit diagram :

Automatic Battery Charger Circuit Diagram

Automatic Battery Charger Circuit Diagram

The circuit has been basically designed for a car battery (about 40 Ah rating), which could be used for lighting two 40W tube lights. The circuit includes Schmitt trigger relay driver,float charger,and battery voltage monitor sections.  The Schmitt trigger is incorporated to avoid relay chattering. It is designed for a window of about 1V. During charging, when the battery voltage increases be-yond 13.64V, the relay cuts off and the float charging section continues to work. When battery voltage goes below 11.66V, the relay is turned on and direct (fast) charging of the battery takes place at around 3A.  In the Schmitt trigger circuit, resistors R1 and R2 are used as a simple voltage divider (divide-by-2) to provide battery voltage sample to the inverting input terminal of IC1. The non-invert-ing input terminal of IC1 is used for reference input derived from the output of IC2 (7806), using the potentiometer arrangement of resistors R3 (18 kilo-ohm) and R4 (1 kilo-ohm).

LED1 is connected across relay to indicate fast charging mode. Diodes D3 and D6 in the common leads of IC2 and IC3 respectively provide added protecion to the regulators.  The float charging section, comprising regulator 7812, transistors T3 and T4, and few other discrete components, becomes active when the battery volt-age goes above 13.64V (such that the relay RL1 is deenergised). In the energised state of the relay, the emitter and collector of transistor T4 remain shorted, and hence the float charger is ineffective and direct charging of battery takes place.

The reference terminal of regulator (IC3) is kept at 3.9V using LED2, LED3, and diode D6 in the common lead of IC3 to obtain the required regulated output (15.9V), in excess of its rated output, which is needed for proper operation of the circuit. This output voltage is fed to the base of transistor T3 (BC548), which along with transistor T4 (2N3055) forms a Darlington pair. You get 14.5V output at the emitter of transistor T4, but because of a drop in diode D7 you effectively get 13.8V at the positive terminal of the battery. When Schmitt trigger switches ‘on’ relay RL1, charging is at high current rate (boost mode). The fast charging path, starting from transformer X2, comprises diode D5, N/O contacts of relay RL1, and diode D7.

The circuit built around IC4 and IC5 is the voltage monitoring section that provides visual display of battery voltage level in bar graph like fashion. Regulator 7805 is used for generating reference voltage. Preset VR1 (20 kilo-ohm) can be used to adjust voltage levels as indicated in the circuit. Here also a pot meter arrangement using resistors R7, R8, and R9 is used as ‘divide by 3’ circuit to sample the battery voltage. When voltage is below 10V, the buzzer sounds to indicate that the safe dis-charge limit has been exceeded.

Author : Yash Deep - Copyright : EFY Mag
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Thursday, April 5, 2012




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