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Color organ with PIC16F84
Flash-back to the 60's with this 5 channel unit with up to 100 watts per channel. This unit uses a PIC16F84 with an 8 bit A/D. The signal from both stereo channels is combined and digitized. Each of 5 frequency bands is processed using a 16 point FFT. Then the level of each channel is output as PWM (pulse width modulation) to a set of solid...
A/D converter 16Bit with LCD and PIC18F2550
The analog to digital converter (ADC) is a commonly required in most of the projects. Analog voltage measurement can be done using the ADC hardware built in together in a PIC. The picture below show a simple setup for measuring the voltage through the adjustment of the potentiometer. PIC used in this example come with a 10 bit ADC. In the...
Surround Sound Decoder
The particular circuit does?t have the requirement to replace the trade decoders Surround, because this they have many more facilities and possibilities. It give however the possibility in many try with this article of decoding. The coding in Stereo Dolby Surround show the tendency to be abandoned and is replaced with digital DTS, Dolby 5.1...
10 Bit analog to digital converter
Study the Analog to Digital capabilities of Atmel ATtiny26. This tiny but mighty IC is really a miracle. One special thing is the internal 10-inputs multiplexed ADC circuit which can covert analog voltages to bytes. This check circuit uses only 3 inputs. Of course you can may changes to use more inputs. I used the AVRISP in-circuit programmer to...
15 x 7 LED display with PIC16F628
This project is provided as a "prototyping project" as no PC board has been produced. The photographs show the project built on a matrix board using surface-mount components and very fine wire. The final design will require a double-sided board with plate-through holes, especially for the matrix of LEDs, but for the moment you can refer to the...
5x7 LED display schematic
Your 5x7 display is my favourite toy; the tunes and graphics in the elevator display always impress my mates! Since building the display I developed my own 400 dot matrix using a pic and the SN74154 [4bit binary to 1 of 16 demultiplexer\counter] - in place of the 4017. It works well but I still have to hook it up to my computer to change the...
Analog to Digital Converter with ADC0808
Normally analogue-to-digital con-verter (ADC) needs interfacing through a microprocessor to convert analogue data into digital format. This requires hardware and necessary software, resulting in increased complexity and hence the total cost. The circuit of A-to-D converter shown here is configured around ADC 0808, avoiding the use of a...
You're simulating a circuit, it requires several digital gates, but you don't have a mixed-mode simulator. What to do? One solution involves creating simplified versions of the logic functions. To do this, we look to the NMOS transistor implementation of logic gates where the transistor acts like a voltage-controlled switch. But, instead of the...
Digital Voice Record and Playback Project by ISD2560P
This project is based on ISD2560P IC which allows you to record 60 seconds voice and then playback it with very high quality. As shown in the schematic, the input soruce is an electret microphone. If a dynamic microphone is used, R2, R3, R4 resistors and C3, C5, C7 capacitors will be omitted and microphone will be connected to the 17 and 18...
High speed data switch circuit
This circuit is a small representation of a very low cost printer sharer i made very long ago. This is as much i can remember of the basic ideas behind the product.
IR S/PDIF Receiver
This simple circuit proves to achieve surprisingly good results when used with the IRS/PDIF transmitter described elsewhere in this site. The IR receiver..
IR S/PDIF Transmitter
The best-known ways to transmit a digital audio signal (S/PDIF) are to use a standard 75? coaxial cable or Toslink optical modules with matching optical c..
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
Digital Signal Integrity
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