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Showing posts from January, 2017

Energy Efficient Backlight

The backlights used in some LCD panels are not exactly economical: typical current draws of 20 mA to 100 mA are common. Normally the current is determined by a series resistor, which leads to additional power losses. It is considerably more efficient, if a little more complex, to use a switching regulator IC. Alternatively, it is often the case that driving the LCD panel is a microcontroller, which we can press into service to provide regulation in software. Fortunately, the regulation does not need to be exceptionally precise. At the heart of our circuit is T1, a p-channel MOSFET, which is driven by an inverted (active low) pulse-width modulated signal from the microcontroller. Component s D1, L1 and C1 form the remainder of the standard step-down switching regulator configuration. In the circuit diagram the LCD backlight is represented by two LEDs; the current flowing through these LEDs is measured by a shunt resistor, filtered, and finally amplified to a level suitable for input to

GUS DriverBoost

50W DC DC Converters TRACOPOWER with the Highest Power Density

TRACOPOWER launches the high performance TEN50 Series with 12 models providing 50W power in a 1”x 2”x 0.4 “ compact package. Today already almost all of applications require a high efficiency of a voltage conversion. When we add to this requirement also saving of space and a galvanic isolation, we´ll get to widely used components – DC/DC modules. The TEN 50 Series models feature a very high efficiency of up to 92%. Excellent efficiency is maintained in over a wide load range and no minimum load is required for an accurate output regulation. They are available in three basic groups – TEN 50-12xx, TEN 50-24xx a TEN 50-48xx with a wide input voltage range (2:1).   Low thermal losses and the use of highest grade components allow an operating temperature range of –40°C to +85°C while up to 55°C no forced air cooling is required. With an optional heat-sink this temperature can even be increased. An operation without a forced air cooling is possible even at higher temperatures – at an adequat

Electronic Quiz Switch Circuit Diagram

One of the common  rounds in the  quizzes is the buzzer round. We are describing here a simple electronic circuit that can be used in any test or quiz competition. In this circuit, only four persons can participate,  and  every  participant is assigned a certain number. Whenever a switch is pressed, the circuit locks the remaining three entries. At the same time, an alarm sounds and the designated switch number is displayed on the seven segment LED display.When a player presses his switch, the corresponding output of IC1 goes high. Let us suppose, when switch S1 is pressed, D1 input of IC1 goes low and its corresponding output Q1 goes high. As a result, current passes through D5 to piezo buzzer PZ1, which creates a beep. At the same time, current also passes through diodes D6-D7 to show the number on the LED display. Simple Electronic Quiz Switch Circuit Diagram Simple Electronic Quiz Switch Circuit Diagram Similarly, when any other switch (S2-S4) is pressed, the corresponding  number

20 Watt Power Amplifier

This IC chip was designed specifically for use in power boosting applications in automobiles. It is self protecting against short circuits and thermal problems. In the bridge configuration shown it will deliver 20 watts of power into a 2 ohm speaker operating at 14.4 volts. 20 Watt Power Amplifier Circuit Diagram

positioning of buchhloz relay

LED Photosensor

It is not always necessary to use special photoresistors or phototransistors to make light-sensitive switches. Although it is not well known, normal visible-light and infrared LEDs will also work. A voltage that depends on the intensity of the natural or artificial illumination falling on the LED can be taken from the anode of the LED. This behaviour can be easily verified by connecting a DVM or oscilloscope directly to the two leads of the LED. Circuit Diagram: LED Photosensor Circuit Diagram Since the load on the photoelectric potential should be kept as small as possible, a JFET is used here as a buffer. The type used is not critical; similar transistors should work equally well. The buffered voltage is fed to the inverting input of comparator IC1. The threshold voltage can be adjusted to meet the desires of the user by means of the potentiometer. A pull-up resistor is connected to the com-parator output, since the LM393 has an open-collector out-put. The supply voltage may be c

Digital control system applications

Digital Control System  is a branch of the control system with continuous time processes in the region associated with the digital controller as the controller of the control elements that control systems and computing discrete time. Depending on requirements, a digital controller can be shaped microcontroller and ASIC to a standard desktop computer. Because the digital computer system is discrete, then the Laplace transform is used in the control system is replaced with the Z-transform. Therefore, you must understand about the concept of continuous time and discrete time concept. Flow Chart - Digital Control system applications Digital computer also has a limited precision (See quantization) extra care needed to ensure that errors in the coefficients, A / D conversion, D / A conversion, etc. do not produce unwanted effects or planned. The application of digital control can easily be done when used in a feedback form. Since the creation of the first digital computer in the early 1940

Build a Car Voltage Regulator Circuit Using LM317

The car cigarette lighter socket does not only light cigarettes, but can be utilized as an electrical channel for powering tools to work on the car such as laptops and other electronic devices. The following circuit diagram shows a way of powering a two-way mobile radio using the LM317 T voltage regulator . The LM317 T is an adjustable 3-terminal positive voltage regulator that efficiently provides a load current of 1.5 Amps over an output range of 1.2 V and 37 V. With reference to the circuit, it can accept 14 volts without any hassle and the voltage can be controlled easily with the use of a potentiometer, a 3-terminal resister with sliding contact. The whole circuit will contain the following components:  Printed Circuit Board (PCB) Resistor 1 (R1): 270 ohms Resistor 2 (R2): 2K carbon potentiometer Capacitor 1 (C1): 100nF Capacitor 2 (C2): 1uF tantalum LM317T Voltage Regulator Heat Sink DC Power Jacks Green LED: Power Red LED: Over Voltage Zener Diode: over voltage LED switch The ze

How to build Fading Red Eyes

Two Light Emitting Diodes slowly light up and fade away due to the circuitry, giving it a feel of blinking red eyes in darkness. It is the perfect way to set up your own horror show in Halloween. It can also be installed in series for the Christmas tree or during Diwali or a decorative power indicator for the daily appliance. A 3 volt linear wave is generated at Pin 1 via LM 1458 IC and followed by a transistor which buffers the emission. A 47 K resistance coupled with a 22uF capacitor is joined at Pin2 to limit the frequency to 0.5Hz. The rate can be varied using a 100K pot(potentiometer) replacing the 47K resistor. Two operational amplifiers govern the circuit. The transitional voltage is produced by the first op-amp which slowly modulates voltage between 3 to 6 volts. The second op-amp supplies alternating voltage of 2 and 7 volts to charge the capacitor and discharge it via constant current. Two 47K resistors establish a fixed voltage when joined across Pin 3 & 6 to keep

Fan Controller Using Just Two Component

Fan Controller Using Just Two Component Circuit diagram. The Maxim MAX 6665 (www.maxim-ic.com) provides a complete temperature-dependent fan controller. It can switch fans operating at voltages of up to 24 V and currents of up to 250 mA. The IC is available from the manufacturer in versions with preset threshold temperatures between +40 °C (MAX6665 ASA40) and +70 °C (MAX6665 ASA 70). The device’s hysteresis can be set by the user via the HYST input, which can be connected to +3.3 V, connected to ground, or left open. The following table shows the hysteresis values available: HYST = Hysteresis open = 1 °C ground = 4 °C +3.3V = 8 °C Fan Controller Using Just Two Component Circuit diagram: Fan Controller Circuit Diagram The other pins of the SO8 package are the FORCEON input and the status outputs WARN, OT and FANON. The test input FORCEON allows the fan to be run even below the threshold temperature. The open-drain output WARN goes low when the temperature rises more than 15 °C above th

Inverter 12VDC to 230V 50Hz

The power inverter can be useful anywhere where you do not have to hand power outlet, like in your car, trailer or cottage. It is powered by mains appliances such as radios, tape recorders, televisions, electric shavers, lamps, Compact fluorescent or charger for mobile phone etc. The maximum load depends on the inverter transformer used as transistors can be up to 150W. Inverter 12VDC to 230V 50Hz Circuit Diagram The source frequency of 50 Hz is known 555 timer, frequency, impact resistance Rx and capacitor Cx. The switching function is performed by two MOS transistors with channel N. The state resistance is only 0.2 R. One is driven directly from the IO, the other through an inverter with BC547. Gate transistors have a relatively large capacity of about 1 nF, must be driven by the least possible resistance. The output resistance of IC 555 is just about the 100R, which is good. BC547 collector resistance must be as small as possible (you can use less of its current is negligible agains

Vocal fader IC

General Description: The BA3837, BA3837F and BA3838F are ICs with an internal secondary active LPF for vocal cancellation functions and mixing amplifier functions with high degrees of vocal cancellation. Three control pins are used to switch between modes: the key controller input mode, through mode, vocal fader mode, sound multiplexing mode and mute mode. By offering these functions on a single chip, these ICs can significantly reduce the number of external components. Circuit diagram: Vocal fader IC Datasheet for BA3837: Download

New leaked Motorola Droid X2 Specifications

Motorola is currently preparing to produce a new variant of the Motorola DROID X and is rumored that the phone will have the name Motorola Droid X2, this phone is also known as the Daytona. We currently have leaked information about the official specs of these phones that we can from the site PocketNow, and here are the features available on these phones: * 1GHz dual-core 2 processor Tegra * 4.3-inch QHD capacitive touchscreen (thats 540,960 pixels) * EV-DO Rev. A connectivity * 8-megapixel camera with dual-LED flash * Wi-Fi 802.11 a / ​​b / g / n * HDMI out * Bluetooth 2.1 + EDR * Proximity, ambient light, accelerometer and compass sensors * 8GB of internal storage The plan of this phone will be bundled by the U.S. Verizon Wireless network.

Simple Miniature Loop Alarm Circuit Diagram

This is the Simple Miniature Loop Alarm Circuit Diagram. The simple construction, reliable operation, very small power consumption, and, most of all, small size. I started with CMOS logic gates, but was soon forced to abandon the concept after a few unsuccessful (and far too complicated) attempts. Then I suddenly realized that a simple transistor switch might do the job and I was right. Simple Miniature Loop Alarm Circuit Diagram Notes As you can clearly see from the schematics, the circuit is utterly primitive and consists of two identical transistor switches. Each has its own alarm LED and they're coupled to a neat 82dB buzzer. The two 1N4148 diodes are used to prevent a signal from one sensor from triggering both LEDs. The sensors used are either wire loops or normally closed reed switches or even a combination of both. You could, for example, tie a wire loop to your suitcase and place a reed switch to the door of your hotel room.Since this little alarm is intended to be kept in

Automatic Turn Off Relay

Per request the circuit today we have relay circuit. It is worth noting again that the diagram provides a time delay of about 0.5 seconds for every microfarad in the value of capacitor C1. This permits delays of up to several minutes. If desired, the delay periods can be made variable by replacing resistor R2 with a fixed and variable resistor in series whose nominal values are approximately equal of the total value of R2 (680K). Automatic Turn Off Relay Circuit Diagram

TRAFFIC LIGHT CONTROL CIRCUIT USING NE555

S S Display Manual i p board

i used ss display and manual i/p board to interface it with 8051 Generic board, of course you can interface it with any other microcontroller.  ICs required for this board are 74hc573 latch, 74hc238 decoder and 74ls48 BCD2dec converter . For their proper working operation refer to their datasheets. 74hc573 is used to store data so that the previous content on SS is not vanish when we disable LE pin. T0 select the proper latch 74hc238, 3x8 decoder is used. And to convert BCD into decimal, 74ls48 converter is used. Note that latches U1 to U4 are connected with C.C SS, so the output of 74ls48 will only go to these latches. Whereas latches U6 and U8 are connected to DP oF SS and LEDs respectfully. You can emit these latches i used them to distinguish between various mode i.e, digital clock, stop watch, counter and manual input etc. For manual input DSW1 is used and J2 is the 8-way connector i used to connect it with 8051 Generic board, same for J1 connector. J3 and three switches are used

The R 2nR DAC

This DAC circuit, otherwise known as the binary-weighted-input DAC, is a variation on the inverting summer op-amp circuit. If you recall, the classic inverting summer circuit is an operational amplifier using negative feedback for controlled gain, with several voltage inputs and one voltage output. The output voltage is the inverted (opposite polarity) sum of all input voltages: For a simple inverting summer circuit, all resistors must be of equal value. If any of the input resistors were different, the input voltages would have different degrees of effect on the output, and the output voltage would not be a true sum. Let’s consider, however, intentionally setting the input resistors at different values. Suppose we were to set the input resistor values at multiple powers of two: R, 2R, and 4R, instead of all the same value R: Starting from V 1 and going through V 3 , this would give each input voltage exactly half the effect on the output as the voltage before it. In other word

Voltage Tester for Model Batteries

With a suitable load, the terminal voltage of a NiCd or lithium-ion battery is proportional to the amount of stored energy. This relationship, which is linear over a wide range, can be used to build a simple battery capacity meter. Circuit Image :   Voltage Tester for Model Batteries Circuit Image  This model battery tester has two functions: it provides a load for the battery, and at the same time it measures the terminal voltage. In addition, both functions can be switched on or off via a model remote-control receiver, to avoid draining the battery when it is not necessary to make a measurement. The load network, which consists of a BC517 Darlington transistor (T2) and load resistor R11 (15 Ω /5 W), is readily evident. When the load is active, the base of T1 lies practically at ground level. Consequently, T1 conducts and allows one of the LEDs to be illuminated. Circuit Diagram : Voltage Tester for Model Batteries Circuit Diagram The thoroughly familiar voltmeter circuit, whi

6 to 15V DC to DC Converter

  A very efficient 6V to 15V DC to DC converter using LM2585 is shown here. LM2585 is a monolithic integrated voltage converter IC that can be used in various applications like flyback converters, boost converters, forward converters, multiple output converters etc. The circuit requires minimum number of external components and the IC can source up to 3A output current. Circuit diagram : 6 to 15V DC to DC Converter Circuit Diagram Here the IC is wired as a boost converter where resistors R1 and R2 are used to set the output voltage .The junction of R1 and R2 is connected to the feedback pin of IC1. Capacitor C4 is the input filter while capacitor C1 the filter for output. Network comprising of resistor R1 and capacitor C2 is meant for frequency compensation. Inductor L1 stores the energy for acquiring boost conversion. Notes:      Assemble the circuit on a good quality PCB. LM2585 requires a heatsink. Output voltage is according to the equation Vout =( (R1/R2)+1) x 1.23. C

12 Volt Battery Voltage Monitor BVM1

The BVM1 is an ultra low power ten LED battery voltmeter circuit that is optimized for monitoring solar-charged 12V battery systems. The circuit features an expanded meter scale that displays ten color-coded voltage steps from 10.5V to 15.0V. Power is conserved by only turning on the appropriate LED for a short but bright flash once every 1.25 seconds. The LED display can be turned on continuously (no blinking) by turning the Calibrate switch on, more battery power is consumed in this mode. BVM1-12 Volt Battery Voltage Monitor With Parts List  The BVM1 also includes a battery low voltage beeper that warns when the battery voltage drops below a preset voltage. The beeper can be turned on and off with the L.V. Beep Activate switch. The BVM1 is protected against reverse voltage connection and is fused for safety. The design goals of this circuit were efficiency, simplicity, reliability and the use of field replaceable parts. The BVM1 circuit has been designed to work in conjunction with

JCM 800 Pre

In sale the new range of Philips UHD TV on OC Android

TP Vision company introduced an expanded line of Philips TV with a resolution of 4K Ultra HD, running the operating system Android. Philips 7900 Series - available 4K Ultra HD TVs that run on Android OS and have a double-sided backlit Ambilight. The second novelty, Philips 9100 series, equipped with powerful features to improve the quality of the image. Two new series offer expanded TP Vision in 4K Ultra HD TVs, which also includes recently introduced models Philips 8800 Series New TV series 7900 and 9100 . As the producer, all 4K Ultra HD TVs Philips Android-based certified by Google. Thus, their owners will be able to access the majority of applications, services and content store Google Play, adapted for use on TV, which significantly enriches the existing offer Philips Smart TV.

Simple Car Battery Voltage Monitor Circuit

This circuit is used to monitor the battery voltage to display a dual-colored LED status of the battery to. If the LED “green”battery voltage exceeds 11.9 volts. If the yellow LED , battery voltage 11.9 to 11.5 volts. If the LED is “red” If the battery voltage below 11.5 volts. You can of course change the trigger points by the trimmer resistors and / or changing the value of the resistors in the divider.  .  Simple Car Battery Voltage Monitor Circuit Diagram . A dual op amp is used as a comparator. The green LED on the board, until the voltage exceeds 11.5 volts. The red LED illuminates when the voltage falls below 11.9 volts to the circuit. Therefore, in the 11.9 to 11.5 volts, both LEDs are on, producing a slightly yellow color. When the voltage falls below 11.5 V, the green LED , and now only the red LED flashes to indicate low voltage. Parts List R1=1K2 R2-3-4=680R R5=15K R6=10K R7-8-9-10=1K IC1=LM324 D1=5V6 /0.5W Zener D2-3-4-5=LED RV1=10K trimmer  Is recommended that multi-

Ibanez Tube Screamer TS808 Compact Mini Tagboard Layout

Steps AVR Programming a Best Chip

This is a complete AVR Tutorial, including avr programming in a very basic & organized way, We will go through by following items. What is an AVR? Using Mac and Windows How AVR programming works Choosing a programmer, to burn the code. Using AVRDUDE Click Here is one for Windows What is a micro-controller? The best way to explain what a microcontroller is, is to start with your computer. Your desktop computer (or laptop) is comprised of multiple parts, a CPU (such as a Pentium or Celeron), some RAM, a hard disk, a keyboard and mouse and a monitor screen. Programs are stored on the hard disk and run on the CPU, with temporary data stored in RAM. You can run multiple programs at a time by having one ‘master program’ called an operating system (such as Linux, Windows or Mac OS X) and that master program keeps track of things for you. AVR Programming Chip The AVR chip has components, too. It has a CPU, some flash storage, some RAM and some EEPROM, all in one little chip!. The CPU is ju

Is Bigger Better in Auto Sound Systems

When it comes to auto sound systems, one question seems to be repeated often-is bigger better? The honest answer to that is not by a long shot. There are many excellent quality sound systems that will not require the backseat and your first-born in order to enjoy wonderful quality of sound and music as you drive along on your daily commute. One thing that is important to remember is that dynamite does in fact come in small packages. The same can be true of a good quality sound system for your car, truck, or SUV. You can elect to have the full range sound package. This package, if not custom installed by the dealer can take up a great deal of real estate within your car, truck, or SUV. If you own a compact car, these types of speakers and this particular type of sound system is definitely not recommended. The first reason it is unattractive is that it will most likely require either the vast majority of your trunk or take out your back seat. I for one like being able to cart around frie

10W Stereo Audio Amplifier Using TDA2009A

This is a schematic of a 10W stereo audio amplifier using TDA2009A amplifier IC. TDA2009A is a good IC provides quality sound. It has built in features like output current protection and thermal protection etc. The circuit can be operate between 8 to 24V DC with 1 to 2 amphere. 10W Stereo Audio Amplifier Circuit Diagram : If you want to operate this 10 watt amplifier circuit with watt amplifier circuit with mains supply then use a filtered and stable power supply to reduce mains hum. 10 watt out put power can be obtained by providing 20V 1.5A to the circuit. Use good and thick heatsink with the IC.  Source By : Circuitsstream

Stereo Tv Decoder Circuit

Ql is an audio amplifier and Ul is used as a 31.5-kHz subcarrier, which is similar to 38-kHz FM MPX.  Pilot frequency is 15.734 kHz.   Stereo Tv Decoder Circuit

Low Cost Universal Battery Charger Schematic

Here is the circuit diagram of a low cost universal charger for NiCD - NiMH batteries. This circuit is Ideal for car use. It has ability to transform a mains adapter in to a charger . This one can be used to charge cellular phone, toys, portables, video batteries, MP3 players, ... and has selectable charge current. An LED is located in circuit to indicate charging. Can be built on a general purpose PCB or a veroboard. I hope you really like it. Picture of the circuit:     A Low Cost Universal Charger Circuit Schematic Circuit diagram: A Low Cost Universal Charger Circuit Diagram Parts: R1 = 120R-0...5W R2 = See Diagram C1 = 220uF-35V D1 = 1N4007 D2 = 3mm. LED Q1 = BD135 J1 = DC Input Socket Specifications: Ideal for in car use. LED charge indication. Selectable charge current. Charges Ni Cd or NiMH batteries. Transforms a mains adapter into a charger. Charge cellular phone, toys, portables, video batteries … Features: LED function indication. Power supply polarity protected. S

Mutron Micro V

Project of Nicad Battery Protection Circuit Diagram

This is a simple Project of Nicad Battery Protection Circuit Diagram. If a NiCad battery is discharged to a point at which the lowest capacity cell becomes fully discharged and reverses polarity, that cell will usually short internally and become unusable.  To prevent this type of damage, this circuit detects a one-cell drop of 1.25 V and turns the load off before cell reversal can occur. Low-current zener or other voltage sensor Dl and resistors Rl and R2 establish a reference level for transistor Ql. These resistors bias the zener to a few microamperes above its `knee.` Therefore, if battery voltage falls more than 1.25 V, Ql turns off, turning off Q2, and disconnecting the load.   Nicad Battery Protection Circuit Diagram After the load is disconnected, if the battery returns to nominal voltage, the high value of resistor shunting Q2 provides enough output voltage to reset the voltage sensor and turn Q2 back on. If desirable, shunt diode D2 or the parasitic diode of the TMOS device,

USB Function Generator Based on AD9833

One tool that I’ve been missing at my lab at home is function generator. They tend to be a bit expensive, so I haven’t bought one. I thought this might be a good opportunity to try and make one myself. I found a pretty common DDS (direct digital synthesis) chip, called AD9833. Then just strap a USB-enabled AVR micro there and maybe some analog electronics.   This board doesn’t do any of the special analog magic to allow for variable amplitude or offset for the signal. The output is fixed to 0-4v. I’m planning to make another completely analog board for adjusting amplitude and offset.

Switch Mode Power Supply Circuit Diagram

The SMPS described here is suit-able for high-wattage stereos and other similar equipment. The circuit employs two high-voltage power transistors (BU208D) which have built-in re-verse-connected di-odes across their collectors and emitters. It can supply about 250-watt out-put. The circuit uses a ferrite core transformer of 14mm width, 20mm height, and 42mm length of E-E cores. An air gap of 0.5 mm is required between E-E junction. Good insulation using plastic-insulating sheets (Mylar) is to be maintained between each layer of winding.  Switch Mode Power Supply Circuit Diagram The number of primary turns required is 90 with 26 SWG wire. The secondary winding employs 17 SWG wire (for 4A load current). Each turn of the secondary develops approximately 2 volts. The reader can decide about the output volt-age and the corresponding secondary turns, which would work out to be half the desired secondary voltage. The volt-age rating of capacitors C7 and C8 should be at least twice the secondar

Flashing Lights Circuit Diagram

This is a simple flashing lights circuit can be used as beacon. The assembly consists basically of two blinking steps that commands two light bulbs. With the help of P1 you can adjust the flashing frequency between some limits. There are 2 parts for the circuit, the second one works the same way as the other but with the help of a wire bridge or a switch you can choose different operating modes.A bridge between M and 3 means: 2 independent blinks. Circuit diagram : Flashing Lights Schematic Circuit Diagram If there is a bridge between M and 2, then the lamps lights alternatively with a frequency that can be adjusted with P1. And finally there is one more possibility for M and 1, where the lamps blinks at the same time. The flashing lights circuit works with voltages between 3V and 15V. The lamps voltage must be 2/3 of working voltage. R5 and R10 are chosen so that the lamps are about to light.

Miniature Loop Alarm

This electronic circuit project of Miniature Loop Alarm. As you can clearly see from the schematics, the circuit is utterly primitive and consists of two identical transistor switches. Each has its own alarm LED and they're coupled to a neat 82dB buzzer. The two 1N4148 diodes are used to prevent a signal from one sensor from triggering both LEDs. The sensors used are either wire loops or normally closed reed switches or even a combination of both. You could, for example, tie a wire loop to your suitcase and place a reed switch to the door of your hotel room. Miniature Loop Alarm Circuit Diagram: Since this little alarm is intended to be kept in arms reach at all times, there aren't any provisions for automatic shutdown after a certain period of time. The buzzer will sound until you turn the whole circuit off or connect the wire loop back to the jumpers. The same goes for the two LEDs, each indicating its own zone. Construction is not critical and there aren't any traps for

Amplifier Circuit 2 X 10 watt with IC AN7145

This is Stereo Amplifier On this schematic amplifier circuit  use the ic AN7145L , but can use the following IC : AN7145M AN7145H AN7146M AN7146H You can use of all ic above. anthis circuit need suply voltage with dual voltage . Minimum voltage 6 Volt and maximum voltage 20 volt . Voltage just (-) and (+), but (-) can also ground. Maximum power output 2 X 20 watt with minimum impedance 4 ohm. Click image to view enlarge. You can operate this circuit with  plugging input to , PC or other media can give signal audio.