Popular Circuits Page 239
- Page 239
-
amplifier input and output impedance, load and source resistance are strongly mutually dependent in the CC circuit. That`s a reason, why "impedance matching" doesn`t achieve results representative for the circuit operation. Analyzing the circuit as CB with....
-
-
Using an odd mix of high voltage diodes although I have some 1200 volt, 6 amp diodes on order which will replace the three HV diodes I`m currently using. The Relay is triggered with a basic transistor circuit and square wave generator. The circu..
-
Now, when the construction is nearly done, here is a circuit diagram. When I finally settled on how it was going to be done, and set it down on paper,....
-
DTL internal structure shown in the inverter circuit (M5936P) is. Inputs with diodes, transistors signal processing, power supply is + 5V. When the input terminal A high level ..
-
Small in size! Big in use Here is a simple and powerful LED circuit that can be operated directly from the AC 100 volt to AC 230 Volts mains supply. The c....
-
Wrap hundreds of turns of magnet wire around the paper tube. Connect this home-made inductor in series with an AC power supply and lamp to form a circuit. When the tube is empty, the lamp should glow brightly. When the steel bar is inserted in the tube, the....
-
-
Finally, white LED`s are bright enough to use in a practical stroboscope. This circuit can operate as a bench-top stroboscope that, in conjunction with an oscilloscope or frequency meter and bench top power supply can accurately measure rotational speeds, or....
-
A 12v battery is being charged from a solar panel. When battery is 12v solar panel is disconnected from battery and connect the load with battery. And again solar panel is connected with battery when battery voltage is say 10v. How to switch simply Which one....
-
From what I understand, an SCR is like a diode that can either be turned on to act like an everyday diode, and it will only turn back off when the power is cut. With this understanding, will this circuit work if not, can you explain even if itdoesn`twork as....
-
An old nonfunctional DVD player donated by the Engineering Department was gutted to provide an appropriate enclosure for the audio amplifier. To mount the nearly 16 lb toroidal transformer and 2in diameter filter capacitors, various sheet metal braces were....
-
This is a simple LED flasher project that uses a common 555 timer IC for its operation. It is configured as an astable mode which means that its output is a square wave oscillator. Two LEDs are connected to its output in such a way that when one LED is ON,....
-
-
The oscillation circuit of the transmitter was added. An oscillation circuit by 555 IC is used for a modified circuit. This is to adjust an oscillation frequency easily. Thereby, it is necessary to change the software...
-
7809 is a voltage regulator integrated circuit(IC) which is widely used in electronic circuits. Voltage regulator circuit can be manually built using parts available in the market but it will take a lot of time to assemble those parts on a PCB. Secondly, the....
-
-
Field effect transistor amplifier has fixed bias input source with feedback. Therefore, the input impedance is very high and very low capacitance. Drive a field effect transist..
-
The operation of a 303MHz circuit has been covered in our project WIRELESS DOORBELL.
We are not going over how the circuit works but explain the importance of some of the components and how they effect the range. The most critical component is the....
-
The circuit you are about to see is the culmination of some effort at improving the basic Link intercom design. You may think that pulse dialing is `old hat` nowadays, but the exercise of building and testing the Link `P` in this format, and understanding....
-
This circuit uses a 555 timer to drive a 4017 counter. The counter outputs drive transistor relay drivers. Time lights "on" can be proportioned by changing connections of outputs of counter. ..
-
The diagram of detail of Fig.2 gives additional precise details: The signal HF collected by the antenna is amplified by T1, framed reel S of agreement L1 and L2. To vary the profit of T1, it is enough to vary its supply voltage. Here it passes from 4v to....
-
As shown in Fig multi-channel temperature measurement circuit. The test circuit consists of a core consisting of 555 one-shot delay circuit. When the button i..
-
-
So there I was, ripping out a solo during a practice on my ""new"" Hammond C2 organ and the sound falls away and gets soft to the point of no....
-
The time can be set with a potentiometer between 1 minute and 1023 minutes, about 17 hours. A pushbutton starts the time, turns on a relais and the timer will turn off the relais when the time is elapsed. It can be switched to seconds for a shorter time....
-
-
This is a design circuit diagram of a moderate power FM transmitter circuit. This circuit is built operation by two transistors. This is a figure of complete circuit. Operation of this circuit is explain as the voice signals picked by the microphone will be....
-
This digital voltmeter is ideal to use for measuring the output voltage of your DC power supply. It includes a 3. 5-digit LED display with a negative voltage indicator. It measures DC voltages from 0 to 199. 9V with a resolution of 0. 1V. The voltmeter is....
-
Ty- Regarding your updated drawing of the AF/PI stage: - I don`t think R45 exists? - The disk cap bypassng R44 is labeled 68NF750 10% which I assume....
-
A high quality stereo FM transmitter circuit is shown here. The circuit is based on the IC BA1404 from ROHM Semiconductors. BA1404 is a monolithic FM stereo modulator that has built in stereo modulator, FM modulator, RF amplifier circuitry. BA1404 FM....
-
The output frequency of this simple low-cost active voltage-controlled oscillator circuit is based upon the inherent frequency dependent characteristics of our operational amplifier. The oscillator circuit shown uses a TL082 op amp. When power is applied,....
-
Here`s a metal detector circuit that frequencies of the two oscillators are then mixed in similar fashion to BFO, to produce an audible heterodyne. On the surface of it, this design would seem to represent little more than a twinned BFO metal detector. What....
-
For proper operation, circuit ground must be connected via a small value, high voltage-rating capacitor to one side of the mains supply socket. The "Live" side is the right one. The purpose of this circuit is to animate shop-windows by means of a capacitive....
-
It provides a fully featured commentator position and a line-level input. The unit has an individual commentator output, with an additional output providing a mix of commentator and line input audio. A limit indicator on the main panel shows when the....
-
Circuit schematic shown in Figure 2-3 ov, rlr, VT2 composition twin direct coupled input amplifier stage, the emitter-VT2 VTr base using local feedback to stabilize its DC oper..
-
There are various obvious methods of rust removal, but these methods are unsuitable for very old or valuable artifacts as they tend to be destructive in use, meaning that along with the rust some of the base metal is also removed. Dissolving the rust with....
-
It will allow your car headlights to flash on and off at the same time or it will cause them to flash alternately. The circuit is based on the 555 timer. It is used in the astable mode. The 555 timer output will go high for an adjustable period of time and....
-
Uses barium titanate transducer as microphone, tuned with 20-mh coil to provide peaks at control frequencies of 38.5 and 41.5 kc. Balanced discriminator detects the two ultrasonic tones. Frequency shift of continuous ultrasonic tone activates tuning-motor....
-
With the circuit shown here the response at one octave off tune is within 10% of the far out response: notch sharpness may be increased or reduced by reducing or increasing.respectively the 68 ohm resistor. Linearity tracking of R8 and R9 has no effect on....
-
This circuit shows a twin-T network connected to an LMl02 to fonn a high-Q, 60-Hz notch filter. The junction of R3 and C3 which is normally connected to ground, is bootstrapped to the output of the follower. Because the output of the follower is a very low....
-
IC TDA7052 is a mono output amplifier in 8-comng Head DI package (DIP). The device is designed primarily for battery-operated portable audio circuits. Features include TDA 7052, no external components needed, no switch-on or switch-off button sounds great....
-
Here is a simple charger circuit for charging SMF(sealed maintenance free ) batteries. The charger circuit being curernt and voltage regulated, can be safely used to charge SMF batteries of 1. 2 AH rating. This circuit was actually designed in response to a....
-
Opening SA, changes the indicator lamp from flashing to steady-lit condition. The 6-V incandescent lamp on the collector of Q2 requires about 0.3 A. A 1-KO load resistor limits Ql"s collector current to about 6 mA. ..
-
This is flashing LED circuit emulate the turning of incandescent lamp. The characteristic of incandescent lamp is that they can`t abruptly change the....
-
This linear amplifier delivers 10-W PEP output; with 1.25-W drive on 10 m. Tl, T2, and T3 are 10 turns of bifilar windings on an FT-50-43 toroidal core. The transformers are broadband. Filters for other bands, if desired, are shown. Note: use #26 wire for....
-
This is a SCR timer circuit. Here, SCR is used to drive the final actuator, the buzzer. The time constanst of this circuit is determined by R1 and C1. The buzzer will sound when C1 charges up to a desired level, it will cause the Q1 to conduct and triggers....
-
-
Security is a prime concern in our day-today life. Everyone wants to be as much secure as possible. An access control for doors forms a vital link in a security chain. The microcontroller based Door locker is an access control system that allows only....
-
We aim to transmit more information by carrying articles. Please send us an E-mail to wanghuali@hqew. net within 15 days if we are involved in the problems of article content, copyright or other problems. We will delete it soon. ..
-
-
LM317HV adjustable regulator is capable of supplying in excess of 1. 5A over a 1. 2V to 57V output range. The design of these high current power supply is very easy, because the LM317HV require just few external resistors to set the output voltage. Further,....
-
If you`ve got a Squeezebox then you`ve probably got an amplifer to go with it. Having to get up and turn the amp on and off when you need it is just far too tedious (especially if your Squeezebox is hidden away in a cupboard or something), so we need a....
-
This simple AVR Programmer able to transfer hex programs to most ATMEL AVR microcontrollers. It is more reliable than most other simple AVR programmers available out there and can be built in very short amount of time. This Programmer support the AVR....
-
-
-
Two reasons why LM101 is well suited to comparator applications are it has a large differential input voltage range and the output is easily clamped to make it....
-
Ultrasonic Cleaning the main role in the use of ultrasonic cavitation. Role in the sound field, there is liquid in the bubble will have high-frequency micro-vibration, when the sound pressure reaches a certain value, the rapid growth of air bubbles and then....
-
20W power amplifier circuit shown in Figure 8-3. It consists of a pre-release level, and promote the level of three parts p power level in order to reduce the large phase shift..
-
As shown for the TDA8358J actual application circuit. Television signal processing circuit input signals are input TDA8358J Hill 1,2 feet, positive sawtooth voltage input pin 1..
-
This is an astable multivibrator? (oscillator) circuit using CMOS inverter. This circuit uses CD4007 or MC14007. This circuit has operating frequency range of ...
-
The ROMs or PROMs must have the correct code for converting the data from the NE5037 -used as address for the ROMs or PROMs-to the appropriate segment driver codes. The displayed amount could easily be converted to degrees Fahrenheit, °F, by the....
-
The purpose of the Kapagen is to suck the free electrons from the Earth. The Earth is a big capacitor which contains free electric charges. If it is possible to create or to find a potential imbalance between two points in the ground, it seems possible to....
-
The first attempt used a small flyback from an old computer and a simple driver based on a 555 IC with AC coupling to the driver transistor, with this schematic diagram. It was assembled in a perforated board and put in a box. The circuit has two possible....
-
-
This circuit allows a 12v relay to operate on a 6v or 9v supply. Most 12v relays need about 12v to "pull-in" but will "hold" on about 6v. The 220u charges via the 2k2 and bottom diode. When an input above 1.5v is applied to the input of the circuit, both....
-
A board design that is supposed to measure a loadcell. We have finally tracked a system accuracy fault down to the amp IC. When we twist the board, the amp IC changes its output. I get +80mV when I twist the board from its 4 corners. I`m using the amount of....
-
This mini metronome gives a linear scaled output and 40 to 208 beats per minute. 1- Q1 and Q2 transistors provide linear frequency variation of IC1 depend....
-
Figure 4-18 by volume potentiometer T (Xi 153AP and tone potentiometer T ( 155AP consisting of volume, tone control circuit circuit, Rx, cx clock oscillation element, the value..
-
A simple seven/7 segment counter circuit with an LED display. This counter circuit diagram is designed using IC CD 4033 as counter,555 Timer IC and seven segment LED Display LT 543....
-
The Mini 3 digit display aka "DVM-module" (digital voltmeter module) can easily be tuned and modified because you have control over the firmware. The key advantages of this module are: The internal reference voltage in the atmega8 microcontroller is 2. 56V.....
-
Fixed three-terminal integrated voltage regulator can be directly used in various electronic devices as a voltage regulator. Since the internal set over current..
-
The automatic porch-light control circuit holds a triac on until a 4020 divider counts a number of 60-Hz powerlinc pulses. The circuit turns off a light after a predetermined time by using pins other than pin 3 of III. Various times can be set...
-
This is a very basic tutorial for atmega32 microcontroller beginners to get started. You can call this little program as Hello World for atmega...
-
-
This is an efficient flyback driver for modern cylindrical rectified television flybacks. Many sites doesn`t provide circuits driving these transformers, they simply say that they are bad. I don`t agree. In fact I built this circuit. I spent a lot of time....
-
The lf555afosc1. pdf file download is the diagram (with notations) of Sub-Tone (CTCSS or "PL") Oscillator, made with the famous 555 timer IC set up for astable-multivibrator operation. The values shown place the tone range near the center of the standard....
-
It is a simple and reliable system for processing human speech. It has the task of altering the tone of the human voice and making it heard as artificial, such as the voice of a robot that, as it is known, is produced by artificial means. This is an easy but....
-
Although a distribution amplifier may accept different input channels and output those to particular outputs. The term is meant to describe something that outputs the same signal to some number of outputs,based on one input. The outputs are identical, and....
-
This device is a stereo amplifier for a high sensitivity stereo parabolic microphone. It can be used for listening to distant sounds. The Big-E can be used with headphones or as an audio source for a stereo tape recorder or a PC sound card. This circuit also....
-
This circuit controls a load (in this case a dc brushless fan) based on a temperature compared with a setpoint. THe transduced is a diode in the forward polarization regime. In fact when forward biased, the forward voltage drop accross a diode has a....
-
You'll find that this is a very easy project to build. It will transmit good quality sound in the FM band ( 88 - 108 mhz ). One inportant item is that the IC chip operates on 3 volts DC. The chip will get destroyed if it is operated on any voltage higher....
-
Battery-operated, ionization chamber smoke detector includes a circuit to generate a unique alarm when the battery reaches the end of its useful life. The circuit uses the MCMOS MC14572 for two alarm oscillators (smoke and low battery)..
-
Self switching Power Supply. One of the main features of the regulated power supply circuit being presented is that though fixed-voltage regulator LM7805 is used in the circuit, its...
-
An Instruction and Reference Book on Radio and Television, Coyne Electrical and Television-Radio School, 1951..
-
-
-
Is based on the FTDI`s USB / serial IC FT-232BM. The adapter has been successfully tested with the following transceivers and software: VX-7R (VX-7R Commander), FT-8900 (FTB-8900), FT-817 (FT-817 Commander and Ham Radio Deluxe) and IC-706MkIIG (Ham Radio....
-
-
-
-
Here we are using the Trigger and Threshold pins (2 & 6) to detect the maximum and minimum levels, respectively. The two voltage comparator op-amps inside the 555 control the output, turning it on/off. Looking at the circuit diagram you will notice that the....
-
This alarm circuit was designed to monitor a mains-powered smoke detector located in a shed (which is used to house dog kennels). It provides complete iso....
-
There are an incredibly large number of TX and RX Modules for micro-controllers. The cheapest I found was $9.99, not bad but I remember seeing FM rece....
-
Attach any I2C client chip (thermo sensors, AD converter, displays, relais driver, to your PC via USB quick, easy and cheap! Drivers for Linux, Windows...
-
The voltage regulator is an LM317T, and should accept up to about 14 volts without problems. It can handle up to 1 amp, but you WILL need a heatsink on the voltage regulator. I also added DC power jacks for input and output on my voltage regulator, a green....
-
The diagram shows telephone control automatic lighting circuit. At night, when telephone rings or master takes up telephone transmitter dialing, the light can lighten; when telephone ringer stopped (no one listen) or on-hook, it can delay 10~40s, then the....
-
-
The drawing below illustrates a multistage light sequencer using descrete parts and no integrated circuits. The idea is not new and I hear a similar circuit was developed about 40 years ago using germanium transistors. The idea is to connect the lights so....
-
Software such as that available on PGM-Fi. org and from Hondata make use of the Honda ECU`s oxygen sensor input to allow real time display and data logging of wideband oxygen sensors. This involves feeding the analogue output of the wideband sensor`s....
-
The ZN414 IC contains an entire automatic gain controlled AM receiver in a small three pin package. With only a few external components, a simple radio with excellent selection and reception can be constructed. Since the chip also uses a low supply voltage....
-
-
Here is an inexpensive way to get slow-moving analog data directly into a spreadsheet on your computer! A simple circuit connects to a serial port and a short Qbasic program gathers and saves 12 bit data to a file. A spreadsheet automatically retrieves the....