Mini-stereo circuit using ic TDA2822

This circuit stereo power amplifier. By use integrated circuit number TDA2822 within be model Dual Amp give power watt at 1W 1W bandwidth expansion rates at 40dB 120kHz use power supply since 1.8V to 15volt and use current 6mA feed power supply 9volt reach the circuit C7 will perform filter fire level smoothly then go to feed power supply give with IC1 at 2 input signal pin will on the left and right that come in to change VR1 and VR2 for fine decrease popularity level has of the sound already coupling change C1 and C2 from that time pass by reach input of IC1 at 7, 8, 6 pin and 5 respectively from that time a signal had that to enlarged then go out 1 pin way.

Which be output of the channel a signal on the left and pin 3 ways are output of the channel on the right by a signal output of left channel and right channel will change C3 and C4 signal coupling reach a loudspeaker. By have R1, C5 and R2 C6 perform eradicate the noise of each the channel goes out.
When using the power supply 9 volt into this circuit.VR1 and VR2 to adjust the signal level of the right and left, the pin 7 and pin 6 of IC1.The amplifier IC1 is out of the output pin 1 and pin 3, through the C4 and C5 coupling signals to the left and right speakers.The C6, R1 and C7, R2 is to reduce noise.

LED warning water the plants with ic 4093

Electronic users love trees. But no time and work and forget Enjoy water the plants.So the trees dry out.This circuit solves this problem.It also allows us to not water the plants with too often.
Operation of the circuit. When the supply to the circuit. IC1 / 1 (IC 4093) will work together R1, R2, D1 and C2 is the Oscillator generator.The output at Pin 11 is a rectangular pulse to IC1/2.To return the logic state is out of the opposite pin 3.In addition, the signal from the pin 11 will be issued to the temple ground. be test point A and test point B.It will be resistance.Make a signal to stimulate IC1/3, IC1/4.Which is parallel to the current output is high enough to make the LED light.The signal from IC1 / 2 VR1 is a fine stream that flows into IC1 / 3 and IC1 / 4. To suit the soil to measure.If the ground for us to measure the humidity Li LED1 will light extinguishes.And if the ground is dry LED1 light depending on adjustments VR1.

Fuse electronic for ic regulator

Power supply, plus the ground, using current up to 1 Amp.Normally used, IC Regulator no. 78XX. When used to power circuits.And the short circuit that occurred.If no fuse various equipment will be damaged.But if there is an electronic fuse circuit for IC number 78XX.Then when the, short-circuit.This circuit will act to stop paying current and voltage immediately.Thus preventing the loss.
When entering the input voltage, the circuit Q1 and Q2 at the circuit, a bi stable multivibrator circuit.The Q1 Q2 will start but will not work.Because, C1 connected to the base pin of Q1.Then, the charging.Therefore, the voltage at Pin Collector ‘s Q1, to bias the base pin of Q3.Through R4, so the Q3 conduct. And Q4 will conduct with.As a result, voltage input to pin 1 of IC1.Cause the output voltage Implemented.If there is a short circuit when? D1 has served as a ground to stand Q2 base pressure of about 0.3 volts, resulting in a loss Q2 stopped. Bi stable circuit has changed the operating environment to run Q1.

Making Q3, Q4 and IC78XX not work. There is no voltage at the output of the circuit.If you want to IC1 output voltage again, switch S1. To reset the circuit to return to work.Or the bi stable multibrator circuit changes state to work again, sure enough Q4 work.
Source: http://www.hqew.net/circuit-diagram/Fuse-electronic-for-ic-regulator_10774.html

Simple USB Geiger Counter

Sylvain submitted his latest project: a geiger counter with a USB interface. Thanks for sharing your nice project!
Reprinted Url Of This Article:

http://www.hqew.net/circuit-diagram/Simple-USB-Geiger-Counter_13057.html

RFID Technology Applications

An RFID system consists basically of two? compo-
nents:
Transponder
(fixed on an object that shall be identified)
Reader
(or interrogator base station)
A transponder includes the IC, and in LF systems
optionally a capacitor and a coil. HF systems only
need a coil, UHF systems an antenna. The reader
generates? an? RF? field? which? is? used? to? transmit
power? and? to? per form? bi-directional,? contactless
data? transmission? (no? connection? or? line-of-sight
necessary).? As? soon? as? a? transponder? or? smart
label gets into the field generated by the reader, the
tag transmits information either immediately or? on
request only. The reader decodes this information,
sends it to a host, or displays it.
RFID Applications
Versatile and flexible products form an Atmel prod-
uct scope that offers solutions for almost all appli-
cations in the main RFID market segments. Atmel’s
products fulfill the market requirements that call for
fast, secure and reliable identification systems.

Manufacturing and Logistics
RFID systems guarantee reliability even in dirty and
harsh environments. Efficient and time-saving sys-
tems? can be? achieved by fast and secure identifi-
cation solutions that do not need direct contact or
line-of-sight.
In? this? area,? accurate? manufacturing? and? logistic
systems enable to save time and money. The envi-
ronmental? and? velocity? factors? especially? play? an
important role.
Typical Applications
- Asset Management
- Material Handling and Assembly Equipment
- Bulk Shipment Tracking
- Pallet Tracking
- Cylinder Tracking
- Pharmaceutical Management
- Garments
- Parcel Services
- Laundry Automation
- Waste Management
Transportation
Convenience and time efficiency are the reasons
why RFID is used? in? the? transportation segment.
With? increasing? travel? the? employment? of? faster
ID systems becomes necessary.? In public trans-
portation, RFID guarantees efficient toll and traffic
management, which prevents queues.
Due to long reading distances required by trans-
portation applications such as contain er tracking,
Atmel? also provides components for active tags.
Several? Atmel? products? address? the? ISO? 14443
standard that is mainly used in public transporta-
tion.
Typical Applications
- Airport Baggage Tagging
- Loading Docks
- Cargo Tracking
- Rail Car Tagging
- Electronic Toll and Traffic Management
- Ticketing
- Fuel and Maintenance Operations
- Electronic Payment
- Parking Structures
Animal Identification
RF? identification? is? significantly? involved? in? the
improvement of livestock? tracking.? Stock? monitor-
ing, breeding or disease control are also supported.
And with the outbreak of various animal epidemics,
secure animal identification is more important than
ever. RFID tags can easily be injected under the ani-
mal’s skin.? This? helps to identify? not? only livestock
but also pets and zoo animals.
In animal sports, RFID systems help prevent manip-
ulation and records the correct time of arrival (e.g. in
pigeon sports).? The standards ISO 11784/85,? also
called FDX-B and FDX-A are supported.
Typical Applications
- Animal Ownership Detection
- Wildlife Tracking
- Animal Tracking
- Fisheries
- Lifestock Tracking
If you need more applications related to RFID, we provide web based or desktop based.development using PHP, Visual Basic and Dot Net.Please Contact me admin@makecircuits.com

Reprinted Url Of This Article: http://www.hqew.net/circuit-diagram/RFID-Technology-Applications_13062.html

Water Level Indicator Use Alarm

This circuit not only indicates the amount of water present in the overhead tank but also gives an alarm when the tank is full. The circuit uses the widely available CD4066, bilateral switch CMOS IC to indicate the water level through LEDs.
When the water is empty the wires in the tank are open circuited and the 180K resistors pulls the switch low hence opening the switch and LEDs are OFF. As the water starts filling up, first the wire in the tank connected to S1 and the supply are shorted by water. This closes the switch S1 and turns the LED1 ON. As the water continues to fill the tank, the LEDs2 , 3 and 4 light up gradually.
The no. of levels of indication can be increased to 8 if 2 CD4066 ICs are used in a similar fashion.
When the water is full, the base of the transistor BC148 is pulled high by the water and this saturates the transistor, turning the buzzer ON. The SPST switch has to be opened to turn the buzzer OFF.
Remember to turn the switch ON while pumping water otherwise the buzzer will not sound! BAT54S     1N5819     ATMEGA64        MMBT3904   FR107

Simplest atmega8 programmer Using LPT Port

* R1-R4 = 220R
Atmega 128 is like other AVR microcontrollers. They are ISP – is in-system programmable. Earlier I wrote an article about AVR ISP programmer where 74HC244 buffer is used. Using buffer is safer for your AVR.
But what if you need 128 atmega programmer without any parts, then you can connect your microcontroller directly to LPT port or use protection resistors (220R) just in case. of course circuit works without resistors, but you put your LPT port at risk.

Just connect GND, SCK, MISO, MOSI and RESET to adequate LPT pins and you can program atmega’s flash memory without removing it from socket. Programming software can be PonyProg. you also need power supply 5v Vcc For IC. if you Using PonyProg make sure the setting like this .

High Voltage Parallel Programmer AVR

AVR has two different programming modes calledParallel Programming Mode(Parallel Mode) andSerial Downloading Mode(ISP mode).
At the Parallel Mode, the device to be programmed is put on the programmer’s socket and 12 volts programming voltage is required to its RESET pin. Communicating between the programmer and the device is done in parallel programming commands, so that the programing speed is two times faster than ISP mode. This programming mode is used to pre-program many devices or/and ISP mode cannot use due to the board design. However, most programmers except STK500 seem not to support this programming mode. Using High voltage parallel programmer can recovery wrong fuse bit setting.
Schematics Download :

USB LCD controller using PIC18F2550

This is very cool project .USB interface is implemented by using PIC18F2550 microcontroller. Using USB LCD module you can view many types of information taken from PC like temperatures, time/date, MP3 song titles, view emails, RSS feeds – all that LCDSmartie or other program supports.

ASTM Protocol

ASTM Format
Analyzers format responds to the ASTM specifications E-1381 & E-1394:
? E-1381: Standard specification for Low Level protocol to transfer messages between
clinical or laboratory instruments and computer systems.
? E-1394: Standard specification for transferring Information between clinical or
laboratory instruments and computer systems.
1. Connection specifications (ASTM E-1381)
1.1. Hardware and software characteristics
You can setup Baud rate, Parity, Stop bit,…
Hardware setting of the interface: Connect the Host and the instrument by the DB9 serial
port.
1.2. Output data characteristics
Characters: ASCII
Maximum message length: 247 characters.
Analyzer manages Xon/Xoff protocol.

ASTM Procotol :

Interruptions
If the emission of results is started, the EOT interruption character will not be taking into
consideration.
On the other hand, if the EOT interruption character is received during the frame
preceding the results, the analyser will close its message by the terminal phase, then will
wait for 20 s before to take the line again.
ASTM Data frame format
A sequential number located after the <STX> charcater is inserted into each Data frame.
Frame number is set to 1 when transfer phase is initialized and is incremented by 1 for
each frame up to 7 and then returns to 0.
Frame number is to permit receiver to distinguish between new and retransmitted frame,
in case of retansmitted frame (after a <NAK> response from Host), frame number is not
incremented: <STX>1…Data…<CR><ETX>xx<CR><LF>

Frame cheksum
According to ASTM E-1381 frame checksum (<STX>1…Data…<CR><ETX>xx<CR><LF>) is
defined as modulo 256 of ASCII values sum between <STX> not included and <ETX>
included characters: 1…Data…<CR><ETX>
nb:It’s Depend on machine spesification . Please read user manual from vendor
Records general format specifications (ASTM 1394)
- Codes of characters
ABX analysers use Standard ASCII characters set with codes between 32 and 127
(Codes from 0 to 31 are reserved for protocol).
The Escape delimiter is not used in the datas sended by analysers.
Data frames encapsulate Records defined by ASTM E-1394 norm, Records themselves
encapsulate ASTM fields.

Car Alarm Arming Horn Beep Canceller

It's a great convenience that most modern cars come with a built in alarm, however it is nothing but noise pollution that the horn sounds when the alarm is armed. Disconnecting the alarm system from the horn relay will eliminate this, but prevent the horn from sounding in the even of an actual alarm. This circuit serves to silence the arming beep yet maintain the alarm by introducing a small delay into the signal. It sits between the alarm and horn relay. The alarm must provide a constant horn signal for at least 3 seconds before the horn relay is activated. That way the quick "beep" will never activate the horn relay, while the constant alarm signal will.

Schematic

Parts

Part Total Qty. Description Substitutions C1 1 0.01uF Ceramic Disc Capacitor   C2 1 100uF 35V Electrolytic Capacitor   R1 1 1K 1/4W Resistor   R2 1 10K 1/4W Resistor   R3 1 15K 1/4W Resistor   R4 1 470 Ohm 1/4W Resistor   D1, D3, D4 3 1N4004 Rectifier Diode   D2 1 Red LED   U1 1 555 Timer IC   K1 1 SPST 12V Automotive Relay   MISC 1 Board, Wire, Socket For U1, Case   http://www.hqew.net/circuit-diagram/Car-Alarm-Arming-Horn-Beep-Canceller_12862.html

IR Remote Switch Circuit

This circuit lets you control any line powered electrical device (a lamp, television, fan, etc.) using any infra-red remote control. Almost everyone these days has a pile of old IR remotes left over from appliances they have long ago disposed of them. With this circuit, you can put them back into use. The circuit looks for any modulated IR source and uses it to control a TRIAC, which then switches any appliance connected to it's socket. For example, you can use it to control the room lighting in your home theater setup using any of the remotes you already have. The circuit is powered using a simple transformerless power supply from the line itself, making it compact and easily built into a light switch, wall box, power bar or even the appliance you wish to control.

Schematic

Printed Circuit Board Layout

Printed Circuit Board Parts Placement

Parts

Part Total Qty. Description Substitutions R1 1 3 Meg 1/4W Resistor   R2 1 1.2 Meg 1/4W Resistor   R3 1 680 Ohm 1/4W Resistor   R4 1 2K 1/4W Resistor   R5 1 4.7K 1/4W Resistor   R6 1 150 Ohm 1/4W Resistor   C1 1 0.001uF Ceramic Disc Capacitor   C2, C5 2 1uF 50V Tantalum Electrolytic Capacitor   C3 1 47uF 50V Tantalum Electrolytic Capacitor   C4 1 10uF 50V Tantalum Electrolytic Capacitor   C5 1 150 Ohm 1/4W Resistor   D1 1 1N4733 5V Zener Diode   D2 1 1N4003 Rectifier Diode   Q1 1 2N6071A TRIAC   U1 1 GP1U52X IR Module   U2 1 MC74HC74 D-Type Flip Flop   U3 1 MOC3011 Opto Isolator   MISC 1 Board, Sockets For ICs, Mains Socket, Mains Plug and Cord, Wire

Simple Colour Organ

Parts

Part Total Qty. Description Substitutions R1 1 500 Ohm Pot   T1 1 500 Ohm/500 Ohm Matching Transformer 1K/1K Matching Transformer SCR1 1 C106Y SCR 106B, Teccor S2003LS1 L1 1 10-100 Watt Lamp   MISC 1 Case, Board, Socket For L1, Line Cord

Notes

1. L1 can be any 10-100 Watt lamp.
2. R1 adjusts sensitivity. The greater the resistance, the less sensitive the colour organ becomes.
3. Since this project is powered by 120 VAC, it must be installed in a case.
4. You can also use the Teccor S2003LS1 SCR for SCR1. These give better sensitivity and brightness than the C106Y units.

Reprinted Url Of This Article: http://www.hqew.net/circuit-diagram/Simple-Colour-Organ_12874.html

Remote Telephone Ringer

This remote telephone bell ringer allows you to use a large (and loud) external bell in place or in addition to the built in (and rather wussy) ringer in most modern telephones. This is ideal for large outdoor areas, noisy shops or those hard of hearing. Most any large bell can be used as the circuit can be easily adjusted for various supply voltages.

Schematic

Parts

Part Total Qty. Description Substitutions C1 1 0.47 300V Capacitor   C2 1 47uF 25V Electrolytic Capacitor   R1 1 1K 1/4W Resistor   R2 1 10K 1/4W Resistor   R3 1 1K Pot   R4 1 2K 1/4W Resistor   Q1 1 6A, 200V TRIAC   Q2 1 6A, 200V SCR (106, Etc.)   D1 1 1N4774 Zener Diode   D2, D3 2 1N4007 Rectifier Diode   U1 1 4N33 Opto Isolator   BELL 1 Large Bell (Fire Bell, School Bell, Etc.)   MISC 1 Board, Wire, Socket For U1, Case

Op Amp Radio

Parts

Part Total Qty. Description Substitutions C1 1 Tuning Capacitor   C2 1 0.1uf Disc Capacitor   R1 1 10 Meg 1/4 W Resistor   D1 1 1N34 Germanium Diode   U1 1 741 Or Similar Op Amp   L1 1 "Loopstick" Antenna   MISC 1 IC Socket, Crystal Earphone, Wire, Antenna

Reprinted Url Of This Article: http://www.hqew.net/circuit-diagram/Op-Amp-Radio_12904.html

Transistor Organ

This simple circuit can provide hours of enjoyment as you learn tunes, play duets or just make some really weird sounds by pushing all the buttons at once. You have probably seen this ciruit before, it is fairly common. I have seen it in several books. The best thing about the circuit is that you can tune each individual note, or go to a whole new octive by changing one capacitor (C1). Because of this, it is possible to from an entire Transistor Organ ensemble. Why you would want to do this is anyone's guess...

Schematic

Parts

Part Total Qty. Description Substitutions R1-R8 8 250K Trim Or Regular Pot   R9, R12 2 100 Ohm 1/4 W Resistor   R10 1 10K 1/4 W Resistor   R11 1 220 Ohm 1/4 W Resistor   R13 1 5K Pot   C1 1 0.01uF Capacitor   C2 1 0.1uF Capacitor   Q1 1 2N4891 Unijunction Transistor   Q2 1 2N2222 Transistor 2N3904 S1-S8 8 SPST Switch   SPKR 1 8 Ohm 2 W Speaker   MISC 1 Wire, Circuit Board, Knobs For Pots

Telephone Recorder

This nifty little circuit lets you record your phone conversations automatically. The device connects to the phone line, your tape recorder's microphone input, and the recorder's remote control jack. It senses the voltage in the phone line and begins recording when the line drops to 5 volts or less.

Schematic

Parts

Part Total Qty. Description Substitutions R1 1 270K 1/4 W Resistor   R2 1 1.5K 1/4 W Resistor   R3 1 68K 1/4 W Resistor   R4 1 33K 1/4 W Resistor   C1 1 0.22uF 150 Volt Capacitor   Q1, Q2 2 2N4954 NPN Transistor   D1 1 1N645 Diode   MISC 1 Wire, Plugs To Match Jacks On Recorder, Board, Phone Plug

Notes

1. The circuit can be placed anywhere on the phone line, even inside a phone.
2. Some countries or states require you to notify anyone you are talking to that the conversation is being recorded. Most recoders do this with a beep-beep. Also, you may have to get permission from the phone company before you connect anything to their lines.

Source: http://www.hqew.net/circuit-diagram/Telephone-Recorder_12910.html

8 Note Tune Player

This neat little circuit can play 8 note tunes at any speed you want. You select the notes with 8 trim pots. The speed in selected through a ninth pot. The circuit draws very little power and can be powered by a 9 volt battery, with the addition of a 7805 regulator to power the TTL logic used.

Schematic

Parts

Part Total Qty. Description Substitutions R1 1 10K Trim Pot   R2 1 1K 1/4 W Resistor   R3, R4, R5, R6, R7, R8, R9, R10 8 500 Ohm Trim Pot   C1, C3 2 10uF 12V Electrolytic Capacitor   C2 1 1uF 12V Electrolytic Capacitor   U1 1 555 Timer   U2 1 7490 Binary Counter 74LS90, 74HC90 U3 1 7445 BCD To Decimal Decoder 74LS45, 74HC45 U4, U6 2 7404 Hex Inverter 74LS04, 74HC04 U5, U7 2 4016 Quad Bilateral Switch   U8 1 3909 LED Flasher/Oscillator   SPKR1 1 8 Ohm 500mW Speaker   MISC 1 Board, Wire, IC Sockets

Notes

1. R1 controls the speed at which the notes are played. R3-R10 control the pitch of those notes.
2. The circuit will operate fine on a 9V battery, with the addition of a 7805 regulator to power the TTL logic used.
3. The missing pin on U2 is pin 14.

Mono To Stereo Synthesizer

This circuit attempts to liven up mono sound sources by simulating a stereo signal. It does this by shifting certain frequencies between left and right to fool the ear. It can often produce a passable mock stereo sound to bring some depth to otherwise flat recordings. Of course, there is no way to produce real stereo sound from a purely mono source unless the synthesizer had a way to tell which direction the original sound came from, but an illusion is generally enough for all but the hard core audiophile.

Schematic

Parts

Part Total Qty. Description Substitutions R1 1 4.7K 1/4W Resistor   R2 1 10K 1/4W Resistor   R3 1 12K 1/4W Resistor   R4, R6 2 22K 1/4W Resistor   R5 1 11.K 1% 1/4W Resistor   R7 1 16K 1/4W Resistor   R8 1 100K 1/4W Resistor   R9 1 24K 1/4W Resistor   R10 1 18K 1/4W Resistor   C1 1 0.1uF Ceramic Disc Capacitor   C2, C3 2 0.47uF Ceramic Disc Capacitor   C4, C5, C7 3 0.01uF Ceramic Disc Capacitor   C6 1 0.013uF Ceramic Disc Capacitor   C8, C9 2 4.7uF 25V Electrolytic Capacitor   C10 1 0.22uF Capacitor   C11 1 47uF 25V Electrolytic Capacitor   C12 1 100uF 25V Electrolytic Capacitor   D1 1 LED (Red, Green or Orange)   U1 1 TBA3810 (442-794)   S1 1 SPDT Switch   S2 1 SPST Switch   J1, J2, J3 3 RCA Jack Other suitable jack MISC 1 PC Board, Wire, Case, Holder for D1, Socket for U1

Source: http://www.hqew.net/circuit-diagram/Mono-To-Stereo-Synthesizer_12902.html

Pine Racecar Victory Judge

I have received countless emails asking for a circuit to tell the user which car won in a pine car (also called Pinewood Derby, Cub Car, Scout Car, etc.) race. This simple circuit takes care of the guesswork, lighting the appropriate LED to indicate the winner.

Schematic

Parts

Part Total Qty. Description Substitutions R1, R2 2 100 Ohm 1/4W Resistor   R3, R4 2 100K 1/4W Resistor   D1, D2 2 Standard LED   SCR1, SCR2 2 6A, 200V SCR (such as the 106B)   S1, S2 2 See Notes   K1 1 Small 12V Relay   MISC 1 Board, Wire Reprinted http://www.hqew.net/circuit-diagram/Pine-Racecar-Victory-Judge_12879.html

SS8550 - 2W Output Amplifier of Portable Radios in Class B Push-pull Operation

Description

SS8550 is 2W Output Amplifier of Portable Radios in Class B Push-pull Operation.

SS8550 Features

• • Complimentary to SS8050
• • Collector Current: IC=1.5A
• • Collector Power Dissipation: PC=2W (TC=25°C)

SS8550 Applications

• •High Collector Current 

Parametrics

Maximum Collector-Base Voltage VCBO	-40 V
Maximum Collector-Emitter Voltage VCEO	-25 V
Maximum Emitter-Base Voltage VEBO	-5 V
Maximum Collector Current –Continuous IC	-1.5 A
Maximum Collector Dissipation PC	0.3 W
Maximum Junction and Storage Temperature Tj,Tstg	-55 to 150 ℃

SS8550 Replacement Parts

BC363

3CK10E

9015

9012

Video Activated Relay

This simple circuit from the May 1996Think Tankcolumn of Popular Electronics activates a relay when it senses a composite video signal. This allows you to use the tuner built into your VCR to turn on and off older TVs that are not equipped with a remote. It can also be used to activate surround sound equipment, turn off the room lights, turn on video game consoles, etc. For such a simple circuit, it is very versatile.

Schematic

Parts

Part Total Qty. Description Substitutions R1, R2 2 10K 1/4 W Resistor R3 1 1K 1/4 W Resistor R4 1 33K 1/4 W Resistor C1 1 1uF Electrolytic Capacitor Q1, Q2, Q3 3 2N2222 NPN Transistor 2N3904 NPN Transistor D1, D2, D3 4 1N4148 Diode K1 1 9V Relay J1 1 RCA Jack MISC 1 Case, wire, board

74HC132      74HC4052         MB6S

Notes

1. Since you may be using this circuit to switch mains voltage, it should be enclosed in a case.
2. The circuit will also work with most line level audio, although you may have to adjust the value of R1.

CD4017 - Counter/Dividers

Description

CD4017B and CD4022B are 5-stage and 4-stage Johnson counters having 10 and 8 decoded outputs, respectively inputs include a CLOCK, a RESET, and a CLOCK INHIBIT signal. Schmitt trigger action in the CLOCK input circuit provides pulse shaping that allows unlimited clock input pulse rise and tall times.

These counters are advances one count at the positive clock signal transition if the CLOCK INHIBIT signal is low. Counter advancement via the clock line is inhibited when the CLOCK INHIBIT signal is high. A high RESET signal clears the counter to its zero count. Use of the Johnson counter configuration permits high-speed operation, 2-input decode-gating and spike-free decoded outputs are normally low and go high only at their respective decoded time slot. Each decoded output remains high for one full clock cycle. A CARRY-OUT signal completes one cycle every 10 clock input cycles in the CD4017B or every 8 clock input cycles in the CD4022B and is used to ripple-clock the succeeding device in a multi-device counting chain.

CD4017 Features

• •Fully static operation
• •Medium-speed operation…10MHZ (typ.) at VDD=10V
• •Standardized, symmetrical output characteristics
• •100% tested for quiescent current at 20V
• •5-V.10-V, and 15-V parametric ratings
• •Meets all requirements of JEDEC Tentative Standard No. 13A, “Standard Specifications for Description of ‘B’ Series CMOS Devices”

More info about CD4017, TLP181, L6562, TL494CN, TDA7388

Inductance measuring adapter for multimeter

For those of us without an actual inductance meter, this project is an easy-to-build way to use an ordinary multimeter (digital or analog) to measure the inductance of coils from about 3 microhenries to 7 millihenries, with an accuracy of about 10%, plenty close enough for most DIY projects.

The inductance tester converts the inductance value of the coil being tested to a voltage which can be measured by a voltmeter. Although a digital multimeter (DMM) will give more accurate results, an ordinary analog volt-ohmmeter (VOM) can be used.

I took this circuit fromthis pageon the QRP Homebrew site and made some modifications to it, described below.

The Circuit



The tester uses 4 NAND gates. The first gate, IC1A, is configured as a simple RC square-wave oscillator, producing about 60KHz on the low range and 6KHz on the high range. The square-wave output is buffered by IC1B and applied to a differentiator formed by R4 and the inductor under test. The stream of spikes produced at pin 9 decay at a rate proportional to the time constant of R3 and the unknown inductor. Because R4 is a constant value, the decay time is directly proportional to the value of the unknown inductor. IC1C squares up the positive-going spikes, producing a stream of negative-going pulses at pin 8 whose width is proportional to the value of the unknown inductor.

The negative spikes are inverted by IC1D (pin 11) and integrated by R5 and C3 to produce a steady DC voltage at the positive meter terminal. The resulting voltage is proportional to the value of the unknown inductor and the frequency of the oscillator. R1 and R2 are used to calibrate the unit by setting a frequency that produces a DC voltage corresponding to the unknown inductance. D1 provides a 0.7 volt constant voltage source that is scaled by R8 to produce a small offset reference voltage for zeroing the meter on the low range.

I added the trimmer R4 to the circuit, to allow some leeway in adjusting the inductance range. You can use this trimmer to raise or lower the range to accommodate the coils you measure. I also added the "calibrate" switch because I'm lazy and didn't want to have to hunt for a piece of wire to short the input connectors to calibrate the adapter.

Since the circuit is powered by a battery, no capacitors are needed on either side of the 5-volt voltage regulator.

Construction

I managed to squeeze everything into a mint tin. I put most of the circuit on one piece of perfboard, and the three trimmers (hi/low and zero) on another small board. The test connectors are standard 5-way binding posts (to accept both wire leads and banana plugs), and I used two tip jacks for the meter connection, to allow standard meter probe tips to be easily connected.





The connector on the left is an external power connector, so I can power the adapter from my 3-to-9-volt boost converter in case I don't have a 9-volt battery and want to use 2 AA cells instead.

Operation

The adapter must first be zeroed. If you've included the "calibrate" switch, close it, or just short the inductor terminals with a piece of wire. With the adapter powered and a meter connected and set to a low range (200 or 2000mV), adjust the control for zero voltage.

Next, you need to calibrate both ranges. You'll need an inductor of a known value. Anything at or above about 100uH will work. Connect the inductor to the binding posts, connect the meter, and adjust the trimmer for the range being adjusted for the correct reading.

On the low range, the adapter gives 1mv for each 1uH. On the high range, 1mv corresponds to 10uH (or 0.01mH).

Once adjusted, I found the adapter to be extremely accurate and reliable, measuring several coils of known inductance. The results are plenty good enough for most electronics hobbyist's needs.

Reprinted Url Of This Article: http://www.hqew.net/circuit-diagram/Inductance-measuring-adapter-for-multimeter_11315.html

Interfacing a Toshiba T6963C Equipped GLCD with a PIC Microcontroller

So you happen to have a GLCD with the Toshiba T6963C display controller and you want to interface it with a PIC and write a driver for it. You've scoured the internet, but the only tutorial you've found that shows how to do it is useless. Well, here I will demonstrate just exactly how to go about doing it.

For this tutorial, our example setup is the Microchip 44-pin Demo board, which features the PIC 16F887, driving a Solomon LM6271FWL 240 x 64 GLCD display. This display has 8K VRAM available as well as both a character generator ROM with built in character map as well as an external CG RAM for user defined characters. This display as you've probably figured out also uses the Toshiba T6963C controller chip.

The Hardware Interface

The physical hardware interface is rather simple. On our GLCD, we have an 8 bit bi-directional data port (lines D0-D7) which you can drive with one of the I/O ports on the PIC. Or if you want a serial interface, you can drive it with a 74HC595 serial in/parallel out latch, but the catch to this is that you cannot read from the display if that's all you use. You could just as well use a 74HC165 parallel in/serial out chip in conjunction with the 74HC595 latch if you need to read from the display. In my example, I am using PORTD on the PIC to direct drive the GLCD's data port.

On the control side of the GLCD, you will have the following lines -

C/D - Command/Data mode select (Command High/Data Low)
CE - Chip Enable (active when low)
READ Mode Select (active when low)
WRITE Mode Select (active when Low)
RESET - Resets the GLCD's controller (reset active when low)
Font Select - Allows you to select either a 6x8 or 8x8 font size (6x8 High/8x8 Low)

On my example display, I'm using the lower 3 bits of PORTA and PORTC to drive these lines as follows -

RA0 - CD
RA1 - RESET
RA2 - Font Select
RC0 - WRITE
RC1 - READ
RC2 - CE

Before we get into how to initialize the display we first need to talk about the power up sequence. On your GLCD, you will find that you have connections for two power supplies. The first supply is the 5V logic supply. This supply powers the GLCD's controller, VRAM chips and all of the logic stuff that makes the GLCD work. The second supply is an adjustable 0-12V negative supply that powers the LCD screen itself. The reason it is adjustable is to provide a means of adjusting the display contrast. This supply should not be on until the logic supply has come up to voltage and the display controller has been run through the initialization sequence. Once the display initialization sequence is complete, you can then apply power to the GLCD from the second supply. This prevents latch up of the CMOS LSI (the T6963C and the LCD driver LSI).

Now let's talk about PIC speed. The setup and hold time for all of the control signals as well as data input/output on the T6963C is between 10 and 150nS. So as long as your PIC instruction clock does not run faster than 200nS per instruction (20MHz Fosc, which results in a 5MHz instruction clock), we don't have to worry about needing "nop" instructions or running delay loops in between control line switching/data throughput. On my example PIC, I'm running a 16MHz crystal, which results in an instruction clock frequency of 4MHz, and instructions are executed at a rate of 250nS per instruction (1/4MHz = 250nS). You can run slower than this if you want. It's not a requirement to run the PIC that fast.

Now that the power up sequence and PIC speed is understood, we can get into what needs to happen for the initialization sequence of the T6963C.

Read more at http://www.hqew.net/circuit-diagram/Interfacing-a-Toshiba-T6963C-Equipped-GLCD-with-a-PIC-Microcontroller_11332.html

Triac light bulb flasher

This 800 W light bulb flasher operates directly off the line and needs no transformer. Power for the timer circuit is derived by limiting the current using a 330 nF capacitor (acts like a 9.6 k resistor at 50 Hz), rectifying with a full-wave rectifier composed of four diodes (you may also use a pre-made bridge rectifier instead of the diodes, of course, but make sure the voltage rating is 400 V, or 250 V RMS). Then the voltage is limited with a 9 V zener diode (almost any of this voltage will work), a 1 W type. The 100 ?F capacitor filters the power, a 16 V rating may be a bit safer. Remember: if the zener diode fails, the capacitor will blow because it gets peaks of up to 330 V, although current-limited). In this configuration, the timer gives long pulses at 1.3 Hz.

Now there's one problem: we can't drive the triac directly, because the controlling voltage is not isolated from the line since there is no transformer. The easiest way to drive it is thus by using a triac optocoupler. The K3021 or MOC3021 is well suited for this purpose, as it works like a small triac and thus allows it to directly drive the gate of the larger triac. The coupler is connected to turn on when the timer outputs a low, so we get short pulses.

Please note that this only works with resistive loads like incandescent light bulbs or heaters. It does not work with fluorescent lamps (need a snubber network to do that).

Graphs and Waveforms Tutorial

Graphs are one way of showing the relationship between two variables (things that can change in value).

The graph above shows how the brightness of the sun is related to the time of day.

From the start at the bottom left hand corner until just before 6 am brightness is zero. (It is dark). Brightness increases as time passes being at maximum about 1 pm when the sun is highest in the sky. Brightness then falls becoming dark at about 9 pm when the sun sets. Now look at the following graph.

This relates a dry battery voltage to time. It falls slowly over the weeks.
This next graph shows a voltage which slowly rises from zero to a maximum value and then falls suddenly to zero again.

This next graph shows the same thing happening but continues repeating. This is called aWAVEFORM.

The next waveform is called a square waveform because of its shape. It is at zero for a time and then shoots rapidly to a maximum value and stays there for a time before falling to zero again.  It then repeats itself continuously.

AnOSCILLOSCOPEis used to display and measure waveforms.
A common waveform is theSINEWAVEwhich can alternate between positive and negative voltages.

Note that the horizontal line in all these graphs is called the X axis and the vertical line is the Y axis.

Frequency Modulation (FM) Tutorial

With AM, the frequency of the carrier is fixed and the modulating signal controls carrier amplitude.
With FM, the amplitude of the carrier is kept constant and its frequency varied by the modulating signal. This variation in carrier frequency is calledDEVIATION.
The amount that the carrier deviates in frequency is proportional to the loudness of the Audio modulating signal. If you shout into the microphone, it deviates more than if you whisper.
Deviation is expressed in kHz per Volt. The BBC uses 15 kHz/Volt. The maximum deviation allowed by theBBCis plus and minus 75 kHz from the carrier frequency.
How often the carrier deviates is determined by the frequency of the modulating audio. If you whistle it deviates more frequently than if you hum into the microphone. Since FM signals occupy a wide bandwidth there is no room for them on LW or MW.
They use the FM band of 88-108 MHz where there is plenty of band space available. Advantages of FM are higher quality and low noise.

The diagram shows how the carrier varies in frequency as the modulating signal changes in amplitude.

Reprinted Url Of This Article: http://www.hqew.net/circuit-diagram/Frequency-Modulation-%28FM%29-Tutorial_11282.html

Light Tutorial

Light is an electromagnetic wave similar to radio waves. It has wavelength and frequency. It travels at 300,000,000 metres per second.

Wavelength, frequency and the speed of light are related. Wavelength x frequency = the speed of light. Different colours of light have different frequencies.
When a ray of light hits a shiny surface it isREFLECTED. The angle of reflection equals the angle of incidence.

When light passes from one transparent material to another it isREFRACTED(bent).
LENSESuse refraction.CONVEXlensesFOCUSa beam of light to a point.

CONCAVE lenses cause the beam to DIVERGE.

ThePRIMARYcolours which make up white light can be separated out by a glass PRISM.

Three of the primary colours, RED, GREEN and BLUE are used in the colour television system.
By mixing them most other colours can be made.
In the next diagram, red and green make yellow, green and blue make cyan and red and blue make magenta.

White is made by using all three colours.

Motor Principle Tutorial

It is best if you read the page on the Magnetism first. When a current is passed through a wire which is suspended in a magnetic field, the wire will move. The direction of movement is determined by the direction of the field and the direction of the current. The speed of movement is determined by the strength of the field and the amplitude of the current.

This principle is used in the electric motor to produce rotation. It is also used in the loudspeaker where varying speech currents through a coil, suspended in a magnetic field, causes movement of a cone, resulting in sound pressure waves.
The moving coil meter uses the same idea. When the meter is connected to a circuit, current passes through a coil. The coil is suspended in a magnetic field, and rotates when current passes through it. A pointer fixed to the coil indicates a value on a scale.
The Electric Generator Principle is related. Here a coil is moved in a magnetic field. This induces voltages and current in the coil.

Reprinted Url Of This Article: http://www.hqew.net/circuit-diagram/Motor-Principle-Tutorial_11290.html

Nicd - Nimh Charger electronic circuit diagram

The charger is build around a LM317 adjustable regulator.
The charge starts when a battery is connected between pins JP1-JP4 or JP2-JP4 or JP3-JP4.
For example, if a battery is connected to JP1-JP4 pins then the current that flows cause a voltage drop to R1, then D1 causes a voltage drop of 0,7 volts and Τ1 conducts. Then through transistor's emitter flows a current that comes from Adjustment pin of LM317.
Diode D4 prevents current to flow from battery back to the charging circuit. Resistors R1,R2 and R3 adjusts the charging current and it's value is given from : Rx=(1,25 0,1) / I , where x = 1,2,3.
I is 1/10 of the battery's charging capacity. For example if battery has a rated capacity of 1700mA then Ι=170.
The input voltage must be at least 3 times the battery's voltage. For example an input voltage of 25V can charge a 8,4V (9V) battery.
R3 is 1/2 Watt and R1 and R2 it's 1/4 Watt.

Regulated 12 Volt Supply electronic circuit diagram

Notes:

This circuit above uses a 13 volt zener diode, D2 which provides the voltage regulation. Aprroximately 0.7 Volts are dropped across the transistors b-e junction, leaving a higher current 12.3 Volt output supply. This circuit can supply loads of up to 500 mA. This circuit is also known as an amplified zener circuit.

Source: Electronics Lab

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Solar Charger For Lead-acid Batteries electronic circuit diagram

This circuit is still under development, but works well as shown.
This circuit is intended for charging lead-acid batteries with a solar panel. The customary diode that prevents the battery from discharging through the solar panel has been replaced by a FET-comparator combination. The charger will stop charging once a pre-set voltage (temperature compensated) has been reached, and recommence charging when the voltage has dropped off sufficiently. The load is disconnected when the baterry voltage drops below 11V and reconnected when it gets back to 12.5V.

The circuit has the following features:
* Charges until Vbat = 13,8V (adjustable), then float charges;
* Shuts down load when Vbat< 11V (adjustable), resets at 12,5V;
* Temperature compensation;
* Will work with cheap and readily available components like LM393 comparators and BUZ11 FETs;
* Uses less than 1.3mA (Attempts to use micropower comparators have failed spectacularly so far, see below);
* Burns less than 20mW in FETs when charging at 0,5A. (More expensive FETs with a lower RDSON will yield even better results).
Note that the charging current is limited only by the solar panel used

Note the funny place of grounding of the first 2 comparators. There's some weirdness here: this bit of the circuit gives me headaches. Two problems:
* If I ground the first two comparators (LM393) in the same place as the third, i.e. not between the FETs, the thing won't work and the battery will discharge over the solar panel. Why? Am I playing to close to the rails? How can this be remedied/improved/redesigned? Do I need a diode between the comparator's imputs?
* If I use micropower comparators like the Texas Instruments TLC393, the comparators blow up spectacularly, but with the standard LM393 everything works fine. Why? What did I miss?
Help would be greatly appreciated!

Next attempt

This one works fine and uses about 0.5mA, but that might improve because I'm not done tweeking yet: