New Circuits Page 199
- Page 199
-
Detailed discussion of how to add current limit or foldback current limit to the linear regulator controllers of the MAX1864. Can be used with other discrete regulator designs such as in MAX1865, MAX1964, MAX1965, MAX8513, and MAX8514. Shows tested c....
-
-
Designed the same thing but for the reason of having a higher output voltage swing for the mono part of the signal. I personally don`t believe/understand Meier`s idea as voltages are just relative anyway aren`t they I haven`t read this entire thread but from....
-
Have you ever seen the stairs to one of the upper stories in your house turn into a waterfall? Or maybe you ve come home to find your aquarium fish trying....
-
-
This is a schematic and block diagram of a 2-MHz frequency counter. It uses and LSI counter/display driver, LCD readout, and a, few logic chips for timebase and timing pulse circuitry. Q2 and Q3 form a signal (input) amplifier. The circuit contains a crystal....
-
The audio amplifier shown here is based on the TDA7240 IC from ST Microelectronics. The TDA 7240 is an integrated audio amplifier IC that can deliver 20 watts of audio output power into a 4ohm load. The IC has minimum external parts count and is available in....
-
-
It is small and compact stereo amplifier is powerful but can easily be used to replace your broken amplifier or new construction, or to make an active speaker, in all cases combined with a preamplifier. With remarkable feature smake it the true Hi-Fi....
-
This pages contain information about building your own version of the Calrec PQ1549 Equalizer, the one found in the Calrec "Polar" desk. This EQ is one of my absolute favorites when it comes to standard IC-based types, so I made this project to make it....
-
The use of diode rectifiers in AC voltmeters with a low lower limit of measurement range (0. 5. 1 V) leads to significant nonlinearity of the scale because of the nonlinearity of current-voltage characteristics of diodes. The use of electronic amplifiers in....
-
Right here is definitely an simple VE7GC Popcorn RF preamplifier by Dick Pattinson. The circuit utilizes a single tuned circuit at the front end and can connect straight to a mixer or product detector in a simple receiver project. Note how Dick provided....
-
A simple mini or small audio amplifier circuit with diagram and schematic using TDA 7052 IC from philips. Ideal to use as a pocket radio amplifier circuit which deliver 2 watts....
-
-
There are many applications where the accuracy of a digital or analogue (bar graph) is not required but something better than a simple low/high indicator....
-
-
This little project came about as a result of a design job for a client. One of the items needed was a mic preamp, and the project didn`t warrant a design such as the P66 preamp, since it is intended for basic PA only. Since mic preamps are needed by people....
-
In this circuit, using a photoelectric coupler can reach 100G? isolation between TTL and relay circuit, it avoids relay noise and peak voltage influencing TTL circuit. When the TTL input singal is high, Q1 turns on, there is no current in LED, and there is....
-
With this voltage regulator extension circuit you can increase the output current up to 10 A. T1 power transistor has a resistor in the emitter and thus th....
-
This design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously, its power output will be comprised in the 9. 5 -....
-
A truly timeless circuit. LM317 is a versatile and highly efficient 1.2-37V voltage regulator that can provide up to 1.5A of current with a large heat sink. It`s ideal for just about any application. This was my first workbench power supply and I still use....
-
It took sometime to develop this interface for Echolink. It uses PIC16F84A and accepts external DTMF from Radio. My Latest Version Foxecho-k7 provides total isolation between Rig And PC and has AGC on received audio. Delay on this project was in part of....
-
-
The following circuit is a simple, cheap and easy build motorcycle alarm. The circuit just required 2 transistors to drive the relay the the relay act as a switch to activate the buzzer. Any number of normally-open switches may possibly be applied. Fit the....
-
This circuit SJT is 1024kHz temperature compensation crystal oscillator. Circuit theoryis asshown. Because output signal level of the circuit is low, the buffer of follow-up transistor VTl is amplified. VTl base bias resistor R2, the load resistor R3, the....
-
This is a simple single-zone burglar alarm circuit. Its features include automatic Exit and Entry delays and a timed Bell/Siren Cut-Off. It`s designed to be used with the usual types of normally-closed input devices such as - magnetic reed contacts - micro....
-
The circuit board I purchased didn`t have a working 48v phantom power voltage converter on it. That was completely fine with me because I wanted to build a 48v DC phantom powermicrophone pre-amp which would be powered by five 9v batteries. It was good luck....
-
The schematic shows the design of a circuit that senses the resistance of the skin and converts it into a useful switching signal....
-
-
Today we would like to offers solutions for a set time for take control relay and take NO. / NC. contact to apply to control other devices. such as disable or enable the device. function of this circuit is using IC555 to determine the pulse and a resistor R1....
-
Above is a schematic diagram of an LM741 light/dark sensor circuit (from the excellent 741 Op-Amp Tutorial by Tony van Roon).The ECG128/NTE128 transistor stipulated can be substituted with any NPN transistor rated at sufficient gain and current for the....
-
The circuits looked at so far depended for their functioning on linear feedback. The magnitude of the signal returned to the negative input was always strictly proportional to that of the output voltage. The result was that within the limits set by the....
-
Here is the circuit of an Arduino-based Panic Alarm! The wiring is very simple so that even a novice can construct this interesting circuit without any difficulty. Arduino is a family of microcontrollers (tiny computers) and a software creation environment....
-
This circuit responds to RF signals bellow the standard broadcast band to over 500MHz and provides an visual, and audible indication when the rf signal is detected. By adjusting the bias of D2 with the R2 potentiometer the circuit can detect low power or....
-
The circuit simply consists of a PIC micro, ICSP interface, an RS232 level translator and an HD44780 LCD. Initially a scrolling message is displayed using show_intro. When a serial input is detected the main program starts. All keys are now either text....
-
If your scope probes are not isolated then it's still no problem because you can connect the grounding leads of your probes to point A and the tips of your probes to points B and C. Yes, the resulting current traces will be inverted, but only if you don't....
-
In this issue, we feature articles on a variety of measurement-and sensor-related embedded design projects. I encourage you to try similar projects and share your results with our editors. Starting on page 14, Petre Tzvetanov Petrov describes a multilevel....
-
The particular interest of the ADL5519 is focused on bandwidth which is specified up to 8GHz (but still usable in 10GHz with reduced dynamic). With two channels, it is possible to measure the power transmitted to the antenna and the reflected wave, to....
-
Air-cored inductor L1 consists of 13 turns of 1mm dia. enamelled copper wire with an inner diameter of 10mm. The completed inductor is pushed over R7 and its terminals soldered to those of the resistor. All electrolytic capacitors must be mounted upright.....
-
An electromagnetic generator without moving parts includes a permanent magnet and a magnetic core including first and second magnetic paths. A first input coil and a first output coil extend around portions of the first magnetic path, while a second input....
-
The article on my RGB LED fader has been one of the most-visited articles on this blog. Since posting it, I`ve designed and built another microcontroller-based RGB LED project, this time controlling the colors from the computer over USB. The AVR needs to be....
-
There are still neighbors that keep annoying you by having loud the TV or the radio? Well I have you the solution. In fact all neighborhood will face your jamming waves at their TVs and radios, so be careful. This Jammer is the improved version of the old....
-
An audio source, like a mixer, preamp, EQ, or a recorder, is fed to the input of the Electronic Crossover Circuit. This signal is either AC or coupling, depending on the setting of switch 51, the non-inverting input of buffer amplifier Ul-a, a section of a....
-
Using the TB2922HQ audio power IC can be designed a very simple and high efficiency power audio amplifier electronic project . TB2922HQ is 2ch BTL audio amplifier for TV or home audio applications. It includes and the pure complementary P-ch and N-ch DMOS....
-
This transmitter can be used for transmitter hunts, for remote key finding, or for radio telemetry in model rockets. It can be tuned to the two meter band or other VHF bands by charging Cl and Ll. 11 is four turns of #20 enameled wire airwound, 0.25 inch....
-
To generate regulated ± 5-V supplies from a pair of dry batteries, the circuit of Fig. 1 is commonly used. In order to give protection from inadvertent reverse connection of a battery, a diode in series with each battery would produce an unacceptable....
-
This field strength meter consists of a tuned crystal detector producing a dc output voltage from a transmitted signal. The dc voltage is used to shift the frequency of a transmitter of 100-mW power operating at 1650 kHz. The frequency shift is proportional....
-
A flashing light of high brightness and short duty cycle is often desired to provide maximum visibility and battery life. This necessitates using an output transistor, which can supply the cold filament surge current of the lamp while maintaining a low....
-
The availability of a seemingly limitless variety of monolithic DAC chips makes it easy to implement most digital-to-analog-conversion applications with a single off-the-shelf device. Sometimes, an unusual set of requirements necessitates a multichip....
-
This circuit uses an MC1373 to form a TV video modulator. The coil and capacitor connected between pins 1 and 2 should be selected to have a parallel resonance at the carrier frequency of the desired TV channel...
-
You use the fully controlled circuit in Figure 1 to parallel-program two-wire serial EEPROMs via the I2C bus. Gang programmers must address all memory devices during a write operation. To verify the memory contents, however, the system must address only one....
-
Figure 1 illustrates the simplified block diagram of a typical high-speed data converter system. The system consists of a bandpass filter, ADC, high-frequency clock, high-speed storage device, and post processing unit. Aside from the MAX104, the....
-
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....
-
Another very simple audio preamp to build. all parts should be available at your very local electronics shop...
-
The purpose is supposedly to account for the fact that human hearing is less sensitive at low and high frequencies than in the upper midrange, and that this variation is dependent upon the sound intensity (SPL). The Fletcher-Munson curve (as it is commonly....
-
This low-power video transmitter is useful for R/C applications, surveillance, or amateur radio applications. Seven transistors are used in a crystal oscillator-multiplier RF power amplifier chain, and a high-level video modulator. A 9- to 14-Vdc supply is....
-
This converter uses a low-pass filter instead of the usual tuned circuit so the only tuning required is with the receiver. The dual-gate MOSFET and FET used in the mixer and oscillator aren"t critical. Any crystal having a frequency compatible with the....
-
When SI (sensor) is closed, power is applied to U2, a dual timer. After a time determined by C2, CI is ene..
-
The simple diode network can stabilize the voltage supplied to CMOS circuitry from a battery. D1 and D2 must have a c..
-
This is the latest version of the Improved Infrared Receiver with Status LED which can control any desktop PC with an ordinary remote control. The project comes along with a small PCB in order to save space. It connects to the serial port as stated in the....
-
The input attenuator uses a commutating capacitor to cancel the input capacitance of the FET buffer (see DC-10 MHz amp schematic). The commutating capacitors are absolutely necessary to cancel the effect of the input capacitance to the DC-10MHz amplifier.....
-
I don`t know why, but people like blinking lights. You see LED chasers everywhere, in TV shows (Knight Rider), movies, and store windows. This schematic is my version of a simple 10 LED chaser. There is no 555 timer used because at my local electronics store....
-
This unit is easily tunable and stable, consumes little power, and costs less than other types of oscillators tlmt operate at the same frequencies. This unusual combination of features is made possible by a design concept that includes operation of the....
-
Teledyne Semiconductor"s Type TSC9402 is a versatile IC. Not only can it convert voltage into frequency, but al..
-
Precise, adjustable control of beats per minute from a largo of 18 to a frenzied, high presto of 500, These beats are produced acoustically through a speaker. A light flashes at the same rate. When SW1 is closed, CI begins to charge through Rl and R2. Cl....
-
This documents ties to clear out one method for connecting Sega 3D glasses to PC serial port for cheap PC virtual reality. This who do no not know what those Sega 3D glasses are. Sega designed special glasses for it`s video game console to be able to produce....
-
This simple circuit drives 6 LEDs in `Knightrider scanner mode`. Power consumption depends mainly on the type of LEDs used if you use a 7555 (555 CMOS version)...
-
The circuit as shown gives the bandpass operation the transfer function calculated from FBP(s) = where = 1 + s/Qo>0 + s2/w02. The cut-off frequency, 0, and the Q-factor are given by 0 = g/C and Q = gR/2 where g is the transconductance at room temperature.....
-
This complete high quality, low noise 5-BAND GRAPHIC EQUALIZER circuit is based around Monolithic Linear integrated circuit LA3600 manufactured by SANYO. This circuit is very easy to build and has good Quality. You can use it with Portable component stereos,....
-
The rectifier input is tied to the input. This makes gain inversely proportional to input level so that a 20-dB drop in input level will produce a 20-dB increase in gain. The output will remain fixed at a constant level. The circuit will maintain an output....
-
The circuit"s frequency of oscillation is/= 2.8/ [C1 x (R1 + R2)]. Using the values shown, the output frequency can be varied from 60 Hz to 20 kHz by rotating potentiometer R2. A portion of IC1"s output voltage is fed to its noninverting input at pin 3.....
-
The circuit furnishes an initial charging voltage of 2.5 V per cell at 25°C to rapidly charge a batt..
-
Voltage variations and power cuts adversely affect various equip- ment such as TVs, VCRs, music systems and refrigerators. This simple circuit will protect the costly equipment from high as well as low voltages and the voltage surges (when power resumes). It....
-
#
This version uses a double sided PCB. Dimensions are approximately the same as the original version.
#
Removed the second push button switch and components for the RS232 serial interface.
#
Added 22K resistor between MCLR input and Vdd. This....
-
In this circuit, audio fed to the control channel is amplified and rectified by Dl and D2. This dc level activates LED D3 via Q2. The light from D3 causes R9, a light-dependent resistor to decrease resistance. As Rll (audio gain) is set higher, more audio....
-
This is a CMOS IC (CD4033) based circuit which can be used to detect presence of mains AC voltage without any electrical contact with the conductor carrying AC current/voltage. Thus it can be used to detect mains AC voltage without removing the insulation....
-
The Dutch magazine Audio & Techniek once published an article about one-way loudspeakers that were based on Audax units 1. Although speakers using just a single full-range unit per audio channel were disregarded in audiophile circles (high intermodulation....
-
Figure 1 shows the various LED-circuit configurations, and Figure 2 shows the timing to generate all three colors from bicolor and tricolor LEDs, although using only one LED`s operating current. Note that the driver for the bicolor LED must be able to sink....
-
The step size of the converter is variable by selection of the high order data bits. The first DAC, A, has a stable reference current supplied via the 10.24 V reference IC and Rl. R2 provides bias cancellation. As shown, only the first 4 MSB inputs are used,....
-
A high-gain amplifier using a UA741 is used to sense relative voltage drop in a conductor, and therefore current i..
-
Another method that helps program development besides a dot LED as the output device is a serial bit. With a serial transmission to a terminal emulator program, developer may then test program running easier than a dot LED. One of my circuit uses PIC16F84....
-
A practical 92% efficient LCD backlight design is a classic
study of compromise in a transduced electronic system.
Every aspect of the design is interrelated, and the physical
embodiment is an integral part of the electrical circuit. The
choice and....
-
-
This High Voltage power supply is able to generate up to 25-30kV DC Output from a 12-24v DC input. With a fully adjustable DC input power supply (0-24V/4A), it is possible to adjust the HV output between 5 to 30kV. This HV power supply use a common flyback....
-
The FM broadcast band was moved immediately after World War II from its original spot just below 50 Mc to the present 88-108 Mc band. Hallicrafters was one company to offer receiving converters for those who had the old FM radio sets. The offerings....
-
Using the bilateral properties of a balanced mixer this transvertcr will produce 6-m output with 2-m inputs. Y1 is a 90-MHz crystal. Note that the input on 2 m is 143 to 144 MHz for 53 to 54-MHz output. This avoids possibility of extraneous 2-m reception....
-
This is a four-channel temperature measurmet adapter that works without external power supply. It will suitable for measureing temperature and logging its data with a PC. The circuit diagram is very simple and no adjustment is required, everybody will able....
-
The overall design went through a number of design changes as I tried one
option after another and in the end, the simplest one won out. I had tried to utilize
all electronic (no relay) circuitry but creating the high power circuits was too much
of a....
-
** UPDATED 2014 ** This project is the original High power mobile phone Jammer circuit, and all updates are posted here. All other versions are just copied from next.gr. First off all you should be very careful how to use this device. Its fully illegal and....
-
The 22 watt amp is easy to build, and very inexpensive. The circuit can be used as a booster in a car audio system, an amp for satellite speakers in a surround sound or home theater system, or as an amp for computer speakers. The circuit is quite compact and....
-
The LTC®4010 and LTC4011 are NiCd/NiMH battery
chargers that simplify Nickel-based battery charger
design and include power control and charge termination
for fast charging up to 16 series-connected cells using a
synchronous buck topology. The LTC4011....
-
Assume the correct phase sequence to be VA-VB-VC. The circuit terminals are connected such that Tl gets connected to phase A and T2 to phase B. The capacitor advances the voltage developed across R2 due to phase "B" by — 60°, while the voltages developed....
-
This device was designed to use two generic-patterned, pre-made, pre-drilled circuit boards that are available from Radio Shack, and other places. Parts consist of: two generic pre-etched and pre-drilled PCBs (printed circuit boards), 136 precision 1%,....
-
The circuit consists of two basic circuits, the oscillator and the detector. The oscillator uses an FET in a Colpitts configuration. The energy circulating in the oscillator tank is coupled through C4 to the detector circuit, where a small diode (D2)....
-
This device provides three channels of 8 bit pulse-width modulation. Output pulse duty cycle ranges from 0 to 255/256 in 255 steps. DACs may be loaded by the DS interface. DAC values may also be copied into the on-chip EERPOM and then automatically be loaded....
-
This project`s purpose is to design a fully automated machine for drilling a printed circuit board, (PCB) blank at a minimum cost and with the minimum amount of custom machining. This low cost philosophy is achieved by adapting the existing mechanical....
-
The pins RA3 to RA0, are used as outputs driving each column LED. The pins RB0 to RB7 are used as outputs driving signal for each column LED. The 74HC154 (Decoder 4 to 16) is the chip that decodes the signal into a binary digit dekaexapsifio. In the left....
-
If found myself in need of a 1 KHz signal source for an experiments. My function/sweep generator was needed as a pulse generator for the same experiment, so I went though my junk box, looking for circuits from long ago that might fill the need, but found....
-
This is a video scan converter to display NTSC video signal into VGA monitor. Normally, the VGA monitor occupies most desk top space, so that everybody will be thinking that if the VGA monitor can be used for video monitor...
-
In the actual device the transistors are bolted to the aluminium case. The schematic diagram shown here represents how the circuit would be built if all components were on-board. Separate paths for load current and voltage sensing allow the battery voltage....
-
Sensitive systems, such as those in aircraft, must withstand fault conditions, thereby avoiding component and system damage, because a sensor failure could cause a catastrophic event to occur. A channel protector, comprising two n-channel MOSFETs connected....
-
This type of reset pulse is ideally provided by this circuit. Because of the high input impedance of the Schmitt trigger, long reset pulse times may be achieved without the excess dissipation that results when both output devices are on simultaneously, as....
-
WinBode traces automatically true and asymptotic Bode diagrams of any F(s) function of the complex pulsation...
Detailed discussion of how to add current limit or foldback current limit to the linear regulator controllers of the MAX1864. Can be used with other discrete regulator designs such as in MAX1865, MAX1964, MAX1965, MAX8513, and MAX8514. Shows tested c....
Designed the same thing but for the reason of having a higher output voltage swing for the mono part of the signal. I personally don`t believe/understand Meier`s idea as voltages are just relative anyway aren`t they I haven`t read this entire thread but from....
Have you ever seen the stairs to one of the upper stories in your house turn into a waterfall? Or maybe you ve come home to find your aquarium fish trying....
This is a schematic and block diagram of a 2-MHz frequency counter. It uses and LSI counter/display driver, LCD readout, and a, few logic chips for timebase and timing pulse circuitry. Q2 and Q3 form a signal (input) amplifier. The circuit contains a crystal....
The audio amplifier shown here is based on the TDA7240 IC from ST Microelectronics. The TDA 7240 is an integrated audio amplifier IC that can deliver 20 watts of audio output power into a 4ohm load. The IC has minimum external parts count and is available in....
It is small and compact stereo amplifier is powerful but can easily be used to replace your broken amplifier or new construction, or to make an active speaker, in all cases combined with a preamplifier. With remarkable feature smake it the true Hi-Fi....
This pages contain information about building your own version of the Calrec PQ1549 Equalizer, the one found in the Calrec "Polar" desk. This EQ is one of my absolute favorites when it comes to standard IC-based types, so I made this project to make it....
The use of diode rectifiers in AC voltmeters with a low lower limit of measurement range (0. 5. 1 V) leads to significant nonlinearity of the scale because of the nonlinearity of current-voltage characteristics of diodes. The use of electronic amplifiers in....
Right here is definitely an simple VE7GC Popcorn RF preamplifier by Dick Pattinson. The circuit utilizes a single tuned circuit at the front end and can connect straight to a mixer or product detector in a simple receiver project. Note how Dick provided....
A simple mini or small audio amplifier circuit with diagram and schematic using TDA 7052 IC from philips. Ideal to use as a pocket radio amplifier circuit which deliver 2 watts....
There are many applications where the accuracy of a digital or analogue (bar graph) is not required but something better than a simple low/high indicator....
This little project came about as a result of a design job for a client. One of the items needed was a mic preamp, and the project didn`t warrant a design such as the P66 preamp, since it is intended for basic PA only. Since mic preamps are needed by people....
In this circuit, using a photoelectric coupler can reach 100G? isolation between TTL and relay circuit, it avoids relay noise and peak voltage influencing TTL circuit. When the TTL input singal is high, Q1 turns on, there is no current in LED, and there is....
With this voltage regulator extension circuit you can increase the output current up to 10 A. T1 power transistor has a resistor in the emitter and thus th....
This design is based on the 18 Watt Audio Amplifier, and was developed mainly to satisfy the requests of correspondents unable to locate the TLE2141C chip. It uses the widespread NE5532 Dual IC but, obviously, its power output will be comprised in the 9. 5 -....
A truly timeless circuit. LM317 is a versatile and highly efficient 1.2-37V voltage regulator that can provide up to 1.5A of current with a large heat sink. It`s ideal for just about any application. This was my first workbench power supply and I still use....
It took sometime to develop this interface for Echolink. It uses PIC16F84A and accepts external DTMF from Radio. My Latest Version Foxecho-k7 provides total isolation between Rig And PC and has AGC on received audio. Delay on this project was in part of....
The following circuit is a simple, cheap and easy build motorcycle alarm. The circuit just required 2 transistors to drive the relay the the relay act as a switch to activate the buzzer. Any number of normally-open switches may possibly be applied. Fit the....
This circuit SJT is 1024kHz temperature compensation crystal oscillator. Circuit theoryis asshown. Because output signal level of the circuit is low, the buffer of follow-up transistor VTl is amplified. VTl base bias resistor R2, the load resistor R3, the....
This is a simple single-zone burglar alarm circuit. Its features include automatic Exit and Entry delays and a timed Bell/Siren Cut-Off. It`s designed to be used with the usual types of normally-closed input devices such as - magnetic reed contacts - micro....
The circuit board I purchased didn`t have a working 48v phantom power voltage converter on it. That was completely fine with me because I wanted to build a 48v DC phantom powermicrophone pre-amp which would be powered by five 9v batteries. It was good luck....
The schematic shows the design of a circuit that senses the resistance of the skin and converts it into a useful switching signal....
Today we would like to offers solutions for a set time for take control relay and take NO. / NC. contact to apply to control other devices. such as disable or enable the device. function of this circuit is using IC555 to determine the pulse and a resistor R1....
Above is a schematic diagram of an LM741 light/dark sensor circuit (from the excellent 741 Op-Amp Tutorial by Tony van Roon).The ECG128/NTE128 transistor stipulated can be substituted with any NPN transistor rated at sufficient gain and current for the....
The circuits looked at so far depended for their functioning on linear feedback. The magnitude of the signal returned to the negative input was always strictly proportional to that of the output voltage. The result was that within the limits set by the....
Here is the circuit of an Arduino-based Panic Alarm! The wiring is very simple so that even a novice can construct this interesting circuit without any difficulty. Arduino is a family of microcontrollers (tiny computers) and a software creation environment....
This circuit responds to RF signals bellow the standard broadcast band to over 500MHz and provides an visual, and audible indication when the rf signal is detected. By adjusting the bias of D2 with the R2 potentiometer the circuit can detect low power or....
The circuit simply consists of a PIC micro, ICSP interface, an RS232 level translator and an HD44780 LCD. Initially a scrolling message is displayed using show_intro. When a serial input is detected the main program starts. All keys are now either text....
If your scope probes are not isolated then it's still no problem because you can connect the grounding leads of your probes to point A and the tips of your probes to points B and C. Yes, the resulting current traces will be inverted, but only if you don't....
In this issue, we feature articles on a variety of measurement-and sensor-related embedded design projects. I encourage you to try similar projects and share your results with our editors. Starting on page 14, Petre Tzvetanov Petrov describes a multilevel....
The particular interest of the ADL5519 is focused on bandwidth which is specified up to 8GHz (but still usable in 10GHz with reduced dynamic). With two channels, it is possible to measure the power transmitted to the antenna and the reflected wave, to....
Air-cored inductor L1 consists of 13 turns of 1mm dia. enamelled copper wire with an inner diameter of 10mm. The completed inductor is pushed over R7 and its terminals soldered to those of the resistor. All electrolytic capacitors must be mounted upright.....
An electromagnetic generator without moving parts includes a permanent magnet and a magnetic core including first and second magnetic paths. A first input coil and a first output coil extend around portions of the first magnetic path, while a second input....
The article on my RGB LED fader has been one of the most-visited articles on this blog. Since posting it, I`ve designed and built another microcontroller-based RGB LED project, this time controlling the colors from the computer over USB. The AVR needs to be....
There are still neighbors that keep annoying you by having loud the TV or the radio? Well I have you the solution. In fact all neighborhood will face your jamming waves at their TVs and radios, so be careful. This Jammer is the improved version of the old....
An audio source, like a mixer, preamp, EQ, or a recorder, is fed to the input of the Electronic Crossover Circuit. This signal is either AC or coupling, depending on the setting of switch 51, the non-inverting input of buffer amplifier Ul-a, a section of a....
Using the TB2922HQ audio power IC can be designed a very simple and high efficiency power audio amplifier electronic project . TB2922HQ is 2ch BTL audio amplifier for TV or home audio applications. It includes and the pure complementary P-ch and N-ch DMOS....
This transmitter can be used for transmitter hunts, for remote key finding, or for radio telemetry in model rockets. It can be tuned to the two meter band or other VHF bands by charging Cl and Ll. 11 is four turns of #20 enameled wire airwound, 0.25 inch....
To generate regulated ± 5-V supplies from a pair of dry batteries, the circuit of Fig. 1 is commonly used. In order to give protection from inadvertent reverse connection of a battery, a diode in series with each battery would produce an unacceptable....
This field strength meter consists of a tuned crystal detector producing a dc output voltage from a transmitted signal. The dc voltage is used to shift the frequency of a transmitter of 100-mW power operating at 1650 kHz. The frequency shift is proportional....
A flashing light of high brightness and short duty cycle is often desired to provide maximum visibility and battery life. This necessitates using an output transistor, which can supply the cold filament surge current of the lamp while maintaining a low....
The availability of a seemingly limitless variety of monolithic DAC chips makes it easy to implement most digital-to-analog-conversion applications with a single off-the-shelf device. Sometimes, an unusual set of requirements necessitates a multichip....
This circuit uses an MC1373 to form a TV video modulator. The coil and capacitor connected between pins 1 and 2 should be selected to have a parallel resonance at the carrier frequency of the desired TV channel...
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....
Another very simple audio preamp to build. all parts should be available at your very local electronics shop...
The purpose is supposedly to account for the fact that human hearing is less sensitive at low and high frequencies than in the upper midrange, and that this variation is dependent upon the sound intensity (SPL). The Fletcher-Munson curve (as it is commonly....
This low-power video transmitter is useful for R/C applications, surveillance, or amateur radio applications. Seven transistors are used in a crystal oscillator-multiplier RF power amplifier chain, and a high-level video modulator. A 9- to 14-Vdc supply is....
This converter uses a low-pass filter instead of the usual tuned circuit so the only tuning required is with the receiver. The dual-gate MOSFET and FET used in the mixer and oscillator aren"t critical. Any crystal having a frequency compatible with the....
When SI (sensor) is closed, power is applied to U2, a dual timer. After a time determined by C2, CI is ene..
The simple diode network can stabilize the voltage supplied to CMOS circuitry from a battery. D1 and D2 must have a c..
This is the latest version of the Improved Infrared Receiver with Status LED which can control any desktop PC with an ordinary remote control. The project comes along with a small PCB in order to save space. It connects to the serial port as stated in the....
The input attenuator uses a commutating capacitor to cancel the input capacitance of the FET buffer (see DC-10 MHz amp schematic). The commutating capacitors are absolutely necessary to cancel the effect of the input capacitance to the DC-10MHz amplifier.....
I don`t know why, but people like blinking lights. You see LED chasers everywhere, in TV shows (Knight Rider), movies, and store windows. This schematic is my version of a simple 10 LED chaser. There is no 555 timer used because at my local electronics store....
This unit is easily tunable and stable, consumes little power, and costs less than other types of oscillators tlmt operate at the same frequencies. This unusual combination of features is made possible by a design concept that includes operation of the....
Teledyne Semiconductor"s Type TSC9402 is a versatile IC. Not only can it convert voltage into frequency, but al..
Precise, adjustable control of beats per minute from a largo of 18 to a frenzied, high presto of 500, These beats are produced acoustically through a speaker. A light flashes at the same rate. When SW1 is closed, CI begins to charge through Rl and R2. Cl....
This simple circuit drives 6 LEDs in `Knightrider scanner mode`. Power consumption depends mainly on the type of LEDs used if you use a 7555 (555 CMOS version)...
The circuit as shown gives the bandpass operation the transfer function calculated from FBP(s) = where = 1 + s/Qo>0 + s2/w02. The cut-off frequency, 0, and the Q-factor are given by 0 = g/C and Q = gR/2 where g is the transconductance at room temperature.....
This complete high quality, low noise 5-BAND GRAPHIC EQUALIZER circuit is based around Monolithic Linear integrated circuit LA3600 manufactured by SANYO. This circuit is very easy to build and has good Quality. You can use it with Portable component stereos,....
The rectifier input is tied to the input. This makes gain inversely proportional to input level so that a 20-dB drop in input level will produce a 20-dB increase in gain. The output will remain fixed at a constant level. The circuit will maintain an output....
The circuit"s frequency of oscillation is/= 2.8/ [C1 x (R1 + R2)]. Using the values shown, the output frequency can be varied from 60 Hz to 20 kHz by rotating potentiometer R2. A portion of IC1"s output voltage is fed to its noninverting input at pin 3.....
The circuit furnishes an initial charging voltage of 2.5 V per cell at 25°C to rapidly charge a batt..
Voltage variations and power cuts adversely affect various equip- ment such as TVs, VCRs, music systems and refrigerators. This simple circuit will protect the costly equipment from high as well as low voltages and the voltage surges (when power resumes). It....
In this circuit, audio fed to the control channel is amplified and rectified by Dl and D2. This dc level activates LED D3 via Q2. The light from D3 causes R9, a light-dependent resistor to decrease resistance. As Rll (audio gain) is set higher, more audio....
This is a CMOS IC (CD4033) based circuit which can be used to detect presence of mains AC voltage without any electrical contact with the conductor carrying AC current/voltage. Thus it can be used to detect mains AC voltage without removing the insulation....
The Dutch magazine Audio & Techniek once published an article about one-way loudspeakers that were based on Audax units 1. Although speakers using just a single full-range unit per audio channel were disregarded in audiophile circles (high intermodulation....
The step size of the converter is variable by selection of the high order data bits. The first DAC, A, has a stable reference current supplied via the 10.24 V reference IC and Rl. R2 provides bias cancellation. As shown, only the first 4 MSB inputs are used,....
A high-gain amplifier using a UA741 is used to sense relative voltage drop in a conductor, and therefore current i..
Another method that helps program development besides a dot LED as the output device is a serial bit. With a serial transmission to a terminal emulator program, developer may then test program running easier than a dot LED. One of my circuit uses PIC16F84....
This High Voltage power supply is able to generate up to 25-30kV DC Output from a 12-24v DC input. With a fully adjustable DC input power supply (0-24V/4A), it is possible to adjust the HV output between 5 to 30kV. This HV power supply use a common flyback....
The FM broadcast band was moved immediately after World War II from its original spot just below 50 Mc to the present 88-108 Mc band. Hallicrafters was one company to offer receiving converters for those who had the old FM radio sets. The offerings....
Using the bilateral properties of a balanced mixer this transvertcr will produce 6-m output with 2-m inputs. Y1 is a 90-MHz crystal. Note that the input on 2 m is 143 to 144 MHz for 53 to 54-MHz output. This avoids possibility of extraneous 2-m reception....
This is a four-channel temperature measurmet adapter that works without external power supply. It will suitable for measureing temperature and logging its data with a PC. The circuit diagram is very simple and no adjustment is required, everybody will able....
** UPDATED 2014 ** This project is the original High power mobile phone Jammer circuit, and all updates are posted here. All other versions are just copied from next.gr. First off all you should be very careful how to use this device. Its fully illegal and....
The 22 watt amp is easy to build, and very inexpensive. The circuit can be used as a booster in a car audio system, an amp for satellite speakers in a surround sound or home theater system, or as an amp for computer speakers. The circuit is quite compact and....
Assume the correct phase sequence to be VA-VB-VC. The circuit terminals are connected such that Tl gets connected to phase A and T2 to phase B. The capacitor advances the voltage developed across R2 due to phase "B" by — 60°, while the voltages developed....
This device was designed to use two generic-patterned, pre-made, pre-drilled circuit boards that are available from Radio Shack, and other places. Parts consist of: two generic pre-etched and pre-drilled PCBs (printed circuit boards), 136 precision 1%,....
The circuit consists of two basic circuits, the oscillator and the detector. The oscillator uses an FET in a Colpitts configuration. The energy circulating in the oscillator tank is coupled through C4 to the detector circuit, where a small diode (D2)....
This device provides three channels of 8 bit pulse-width modulation. Output pulse duty cycle ranges from 0 to 255/256 in 255 steps. DACs may be loaded by the DS interface. DAC values may also be copied into the on-chip EERPOM and then automatically be loaded....
The pins RA3 to RA0, are used as outputs driving each column LED. The pins RB0 to RB7 are used as outputs driving signal for each column LED. The 74HC154 (Decoder 4 to 16) is the chip that decodes the signal into a binary digit dekaexapsifio. In the left....
If found myself in need of a 1 KHz signal source for an experiments. My function/sweep generator was needed as a pulse generator for the same experiment, so I went though my junk box, looking for circuits from long ago that might fill the need, but found....
This is a video scan converter to display NTSC video signal into VGA monitor. Normally, the VGA monitor occupies most desk top space, so that everybody will be thinking that if the VGA monitor can be used for video monitor...
In the actual device the transistors are bolted to the aluminium case. The schematic diagram shown here represents how the circuit would be built if all components were on-board. Separate paths for load current and voltage sensing allow the battery voltage....
This type of reset pulse is ideally provided by this circuit. Because of the high input impedance of the Schmitt trigger, long reset pulse times may be achieved without the excess dissipation that results when both output devices are on simultaneously, as....
WinBode traces automatically true and asymptotic Bode diagrams of any F(s) function of the complex pulsation...
