Matt circuit

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 for all manner of projects, this little board may be just what's needed for interfacing a balanced microphone with PC sound cards or other gear. Unlike most of my boards, this one is double-sided. I normally avoid double-sided PCBs for projects because rework by those inexperienced in working with them will almost certainly damage the board beyond repair. I consider this not to be an issue with this preamp, because it is so simple. It is extremely difficult to make a mistake because of the simplicity. As you can see, the board uses a PCB mounted XLR connector and pot, so is a complete mic preamp, ready to go. Feel free to ignore the terminals marked SW1 (centred between the two electrolytic supply caps), as they are specific...

The circuit is a MOSFET based linear voltage regulator with a voltage drop of as low as 60 mV at 1 ampere. Drop of a fewer millivolts is possible with better MOSFETs having lower  RDS(on)  resistance. The circuit in Fig.1 uses 15V-0-15V secondary output from a step-down transformer and employs an n-channel MOSFET IRF540 to get the regulated 12V output from DC input, which could be as low as 12.06V. The gate drive voltage required for the MOSFET is generated using a voltage doubler circuit consisting of diodes D1 and D2 and capacitors C1 and C4. To turn the MOSFET fully on, the gate terminal should be around 10V above the source terminal which is connected to the output here. The voltage doubler feeds this voltage to the gate through resistor R1. Adjustable shunt regulator TL431 (IC2) is used here as an error amplifier, and it dynamically adjusts the gate voltage to maintain the regulation at the output. Circuit Fig.1 With adequate heatsink for the MOSFET, the circuit can provide up...

This is a circuit that detects tesões 1.8 V up to 230 Volts AC or DC. This circuit is not a novelty, but it proved so useful, simple and cheap that every technician should have one on the bench. When the tip (red) positive is connected to a positive DC voltage and the black lead to the negative, the red LED lights up. Reversing the polarity green LED lights. Connecting the probes to an AC source both LEDs will light. The lamp current is limited to 40mA @ 220V AC LED for illuminating and a filament starts from about 30V, shining more intensely with increasing tension. Therefore, due to the behavior of the lamp filament, any voltage in the range from 1.8 to 230 V can be detected without changing component values​​.   Ultra voltmeter and Voltage sensing Circuit Diagram   List of Components D1________5 or 3mm. red LED D2________5 or 3mm. Green or yellow LED LP1_______220V 6W lamp filament P1________ Tip multimeter red P2________ Probe Multimeter Black

Ultra Fast Battery Chager for Nickel-Cadmium battery cells [NiCad] which will be discussed in this article is Fast NiCad Battery Charger, called the Ultra Fast Charger Battery Charger NiCad because it can make filling fast NiCad Batteries Cell. A battery charger in Desai has a fast charging capabilities such as Ultra Fast Battery Chager for Nickel-Cadmium battery cells [NiCad] on this article shall be equipped with some ability to protect the battery and charger circuit itself. Feature owned by Ultra Fast Battery Chager for Nickel-Cadmium battery cells [NiCad]  Autoshut-off, is the ability of the charger to stop charging current to a NiCad battery if the capacity NiCad battery is fully charged. Polarity Protection, with the existence of this capability so if there are mounting the battery on the charger upside yan can be known. Constant output voltage Output currents enough to fill some NiCad batteries at once in parallel. Short Circuit Protection, with the existence of this protec...

This is a simple project of Ultra-Bright LED Lamp Circuit Diagram. This ultra-bright white LED lamp works on 230V AC with minimal power consumption. It can be used to illuminate VU meters, SWR meters, etc. Ultra-bright LEDs available in the market cost Rs 8 to 15.These LEDs emit a 1000-6000mCd bright white light like welding arc and work on 3 volts, 10 mA. Their maximum voltage is 3.6 volts and the current is 25 mA. Anti-static precautions should be taken when handling the LEDs. Ultra-Bright LED Lamp Circuit Diagram Fig.1: Ultra-Bright LED Lamp Circuit Diagram The LEDs in water-clear plastic package emit spotlight, while diffused type LEDs have a wide-angle radiation pattern. This circuit (Fig. 1) employs capacitive reactance for limiting the current flow through the LEDs on application of mains voltage to the circuit. If we use only a series resistor for limiting the current with mains operation, the limiting resistor itself will dissipate around 2 to 3 watts of power,whereas no powe...