50 Watt Amplifier Circuit

This is a handy, easy to build general purpose 50 watt amp. The amp has an input for a radio, TV, stereo or other line level device. It also has a phono input for a record player, guitar, microphone or other un-amplified source. With the addition of a low pass filter at the input, it makes a great amp for a small subwoofer. Parts List- R1 - 1 - 200 Ohm 1/4 W Resistor R2 - 1 - 200K 1/4 W Resistor R3 - 1 - 30K 1/4 W Resistor R5 - 1 - 1K 1/4 W Resistor R6 - 1 - 5K 1/4 W Resistor R7,R10 - 2 - 1 Meg (5%) 1/2 W Resistor R8,R9 - 2 - 0.4 Ohm 5 W Resistor R11 - 1 - 10K Pot R12,R13 - 2 - 51K 1/4 W Resistor R14 - 1 - 47K 1/4 W Resistor C1 -...

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Transformerless Power Supply

Parts List- C1 - 1 - 0.39uF 250V Capacitor C2 - 1 - 220uF 25V Electrolytic Capacitor D1 - 1 - 1N4741 11V Zener Diode (See Notes) BR1 - 1 - 1 Amp 200V Bridge Rectifier MISC - 1 - Line Cord, Board, Wire, Case Notes- 1. The value of C1 can be increased to increase the amount of current the circuit can supply. With the values shown, the circuit can supply up to about 15mA. Remember to increase the size of C2 also. 2. <>A different value can be used for D1 to increase or decrease the voltage as needed. 3. Please note that this circuit is not isolated from 120VAC. Because of this, the circuit must be treated with caution and encosed at...

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Fixed Voltage Power Supply

Parts List- C1 - 1 - 2200uF 35V Electrolytic Capacitor C2, C4 - 2 - 0.1uF Ceramic Disc Capacitor C3 - 1 - 10uF 35V Electrolytic Capacitor D1, D2 - 2 - 1N4007 Silicon Diode BR1 - 1 - 2A 30V Bridge Rectifier U1 - 1 - Regulator (See Notes) T1 - 1 - Transformer (See Notes) S1 - 1 - SPST 2 Amp Switch F1 - 1 - 2A 250V Fuse and Holder MISC - 1 - Heatsink For U1, Line Cord, Case, Wire Notes- 1. Since this project operates from 120 (or 220, or 240, etc.) volts AC, it MUST be built inside a case. 2. U1 will reauire a heatsink. 3. You will need to choose T1 and U1 to match the voltage you want. Use the table below as a reference. Output Voltage ...

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Laser Power Supply

Parts List- R1 - 1 - 10 Ohm 10W Or Greater Resistor R2 - 1 - Ballast Resistor, See "Notes" D1, D2, D3 - 3 - 1N4007 Silicon Diode C1, C2, C3 - 3 - 0.1 uF 2000V Capacitor T1 - 1 - 9V 1A Transformer S1 - 1 - 115V 2A SPST Switch MISC - 1 - Case, Wire, Binding Posts (for output), Line Cord Notes- 1. T1 is an ordinary 9V 1A transformer connected backwards for step up. 2. R1 MUST be installed on a LARGE heatsink. A good heatsink is the metal case the supply is built in. 3. R2 Protects the laser tube from excess current. It should be soldered directly to the anode terminal on the tube. To find R2, start with a 500K 10W resistor and work down...

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