Matt circuit

9V battery operated add-on unit for moving magnet pick-ups Two-stage Series/Shunt feedback RIAA equalization This unit was designed for amateurs owning an old collection of vinyl recordings and wanting to have it digitally remastered into a personal computer. Or sometimes they would listen to an old, invaluable, LP collection through their modern High Fidelity chain, usually lacking a phono preamp stage: this is a circuit capable of satisfying their needs. The unit is powered by a 9V battery, allowing a quick and easy connection to all high-level input preamplifier stages and the very low current drawing of the circuit will guarantee a long battery life. Circuit diagram : Portable Phono Preamplifier Circuit Diagram Despite the low voltage supply, circuit performance with moving magnet pick-ups is quite good, featuring high input overload capability, very low distortion and accurate reproduction of the RIAA equalization curve, thanks to a two-stage op-amp circuitry in which the R...

Can be fitted into a packet of cigarettes, Also suitable as Fuzz-box This small amplifier was intended to be used in conjunction with an electric guitar to do some low power monitoring, mainly for practice, either via an incorporated small loudspeaker or headphones. The complete circuit, loudspeaker, batteries, input and output jacks can be encased in a small box having the dimensions of a packet of cigarettes, or it could be fitted also into a real packet of cigarettes like some ready-made units available on the market. This design can be used in three different ways: Loudspeaker amplifier: when powered by a 9V alkaline battery it can deliver about 1.5W peak output power to the incorporated loudspeaker. Headphone amplifier or low power loudspeaker amplifier: when powered by a 3V battery (2x1.5V cells) it can drive any headphone set type at a satisfactory output power level or deliver to the incorporated loudspeaker about 60mW of output power. This configuration is useful for saving ba...

This is a portable battery powered USB charger circuit. This circuit is able to charge your PDAs, Ipods, Mp3 players and any device that plug in to a computer USB to charge. If you fit this circuit in a small box with a 9V battery then it will become a portable emergency USB charger. Simple Portable battery Powered USB Charger Circuit Diagram The schematic is so simple using only few components so you can make this circuit in some minutes if all parts available with you. The circuit is using low dropout regulator IC LM7805 which is easily available in the market and it is also very cheap. The circuit takes voltage from 9V battery and step down the voltage in to a DC 5V output.

This circuit was designed to charge Nicad battery packs in the range of 4.8 to 15.6 V from a convenient remote power source , such as automobile battery. When power is first applied to the circuit applied to the circuit , a small bias current supplied by R1 via winding L1 , starts to turn on the transistor TR1. This forces a voltage across L2 and the positive feedback given by the coupling of L1 and L2 causes the transistor to turn hard on , applying the full supply across L2. The base drive voltage induced across L1 makes the junction the necessary base current to hold Q1 on. Component List Resistor R1 = 1M R2 = 120R R3 = 10R R4 = 39R Capacitor C1 = 100uF 25V C2 = 0.01uF C3 = 4700pF C4 = 100uF 25V Diode D1 = 1N4148 D2 = BYV27-5 D3 = BYV27-5 Transistor Q1 = ZTX650 Transformer L1 = 12T 36awg L2 = 13T 36awg L3 = 20T 30awg L4 = 40T 30awg Core FX3437 with gap of 0.08mm Former DT2492

This is a small, portable set, designed for those aiming at look improvement. The Bio-Stimulator provides muscles' stimulation and invigoration but, mainly, it could be an aid in removing cellulite. Tape the electrodes to the skin at both ends of the chosen muscle and rotate P1 knob slowly until a light itch sensation is perceived. Each session should last about 30 - 40 minutes.  Portable Muscular Bio-Stimulator Circuit diagram : Portable Muscular Bio-Stimulator Circuit Diagram C1 generates 150µSec. pulses at about 80Hz frequency. Q1 acts as a buffer and Q2 inverts the polarity of the pulses and drives the Transformer. The amplitude of the output pulses is set by P1 and approximately displayed by the brightness of LED D1. D2 protects Q2 against high voltage peaks generated by T1 inductance during switching. Parts : P1-----4K7 Linear Potentiometer R1-----180K   1/4W Resistor R2-----1K8  1/4W Resistor (see Notes) R3-----2K2  1/4W Resistor R4-----100R   ...

Portable GSM900 Cellular Phone Jammer Circuit Diagram Emits a carrier that sweeps the 925-960 MHz cellular tower transmitter band (handset receive band)  GSM900 Cellular Phone Jammer Circuit Diagram

This is a project of Portable Microphone Preamplifier Circuit Diagram. This circuit is mainly intended to provide common home stereo amplifiers with a microphone input. The battery supply is a good compromise: in this manner the input circuit is free from mains low frequency hum pick-up and connection to the amplifier is more simple, due to the absence of mains cable and power supply. Using a stereo microphone the circuit must be doubled. In this case, two separate level controls are better than a dual-ganged stereo potentiometer. Low current drawing (about 2mA) ensures a long battery life.  . Circuit Operation: The circuit is based on a low noise, high gain two stage PNP and NPN transistor amplifier, using DC negative feedback through R6 to stabilize the working conditions quite precisely. Output level is attenuated by P1 but, at the same time, the stage gain is lowered due to the increased value of R5. This unusual connection of P1, helps in obtaining a high headroom input, allow...

This is a project of  Mini Portable Guitar Amplifier Circuit Diagram. Can be fitted into a packet of cigarettes, Also suitable as Fuzz-box. This small amplifier was intended to be used in conjunction with an electric guitar to do some low power monitoring, mainly for practice, either via an incorporated small loudspeaker or headphones. The complete circuit, loudspeaker, batteries, input and output jacks can be encased in a small box having the dimensions of a packet of cigarettes, or it could be fitted also into a real packet of cigarettes like some ready-made units available on the market. This design can be used in three different ways: Loudspeaker amplifier: when powered by a 9V alkaline battery it can deliver about 1.5W peak output power to the incorporated loudspeaker. Headphone amplifier or low power loudspeaker amplifier: when powered by a 3V battery (2x1.5V cells) it can drive any headphone set type at a satisfactory output power level or deliver to the incorporated loudsp...

This is a small, portable set, designed for those aiming at look improvement. The Bio-Stimulator provides muscles' stimulation and invigoration but, mainly, it could be an aid in removing cellulite. Tape the electrodes to the skin at both ends of the chosen muscle and rotate P1 knob slowly until a light itch sensation is perceived. Each session should last about 30 - 40 minutes. Circuit diagram : Portable Muscular Bio-Stimulator Circuit Diagram C1 generates 150µSec. pulses at about 80Hz frequency. Q1 acts as a buffer and Q2 inverts the polarity of the pulses and drives the Transformer. The amplitude of the output pulses is set by P1 and approximately displayed by the brightness of LED D1. D2 protects Q2 against high voltage peaks generated by T1 inductance during switching. Parts : P1-----4K7 Linear Potentiometer R1-----180K   1/4W Resistor R2-----1K8  1/4W Resistor (see Notes) R3-----2K2  1/4W Resistor R4-----100R   1/4W Resistor C1-----100nF  63V Polyester Capacitor ...

This portable AM and FM radio circuit is designed using the LA1800 IC and some other external components. As you can see in this circuit diagram the LA1800 manufactured by Sanyo Semiconductors , require few additional components. The LA1800 am FM portable radio circuit needs to be powered from a 3 volt DC power supply circuit. You can use an 3 volt battery. This radio receiver circuit has a low current dissipation of 5.6mA for FM band and 3.2mA for AM band .Also the output signal is driven into earphone speakers , but you can use an additional speaker ( in that case you need to connect an additional small power audio amplifier).