## Circuit-Zone.com - Electronic Projects

Dome Light Dimmer With Delay For Cars
Posted on Wednesday, November 17, 2010   •   Category: Miscellaneous

12V to +-20V Automotive Power Converter (for audio amplifier)
Posted on Wednesday, November 17, 2010   •   Category: AC / DC Innveters

The limitation of car supply voltage (12V) forces to convert the voltages to higher in order to power audio amplifiers. In fact the max audio power x speaker (with 4 ohm impedance) using 12V is (Vsupply+ - Vsupply-)^2/(8*impedance) 12^2/32 = 4.5Watts per channel, that is laughable... For powering correctly an amplifier the best is to use a symmetric supply with a high voltage differential. for example +20 - -20 = 40Volts in fact 40^2/32 = 50 Watts per channel that is respectable. This supply is intended for two channels with 50W max each (of course it depends on the amplifier used). Though it can be easily scaled up or the voltages changed to obtain different values.

500W 12 Volt to 220 Volt Inverter
Posted on Wednesday, November 17, 2010   •   Category: AC / DC Innveters

This is circuit Inverter 12VDC to 220V 50Hz 500W. It easy to make and low cost.

12V to 220V 100W Transistor Inverter
Posted on Wednesday, November 17, 2010   •   Category: AC / DC Innveters

12V to 220V 100W transistor based power inverter.

100W Power Amp
Posted on Wednesday, November 17, 2010   •   Category: Amplifiers

This is a 100W Transistor based Power Amp Circuit. It's an old circuit, but nice circuit amplifier. Uses transistors MJ15003 and MJ15004, power supply +38V,-38V 3A. Output power is 100W for 8 OHM Speaker.

OCL Power Amp
Posted on Wednesday, November 17, 2010   •   Category: Amplifiers

This is old circuit Power amp OCL, But easy circuit and very nice. To use for play music in your home. It low cost too. It use IC 741 or LF351(good) and Transistor x 4 (2N3055+MJ2955+BD139+BD140) and little component. Power supply volt +35V/-35V and 3A for Mono, 5A for Stereo.

Stereo Tone Control Circuit with Adjustable Bass-Treble
Posted on Wednesday, November 17, 2010   •   Category: Amplifiers

PCB Tone control adjustable bass-treble Stereo by IC LM348

Loudspeaker Protection with Soft Start
Posted on Wednesday, November 17, 2010   •   Category: Amplifiers

This is a small protection circuit from loudspeakers, from DC voltage that likely to exist after some damage in the power amplifier. If a DC voltage is presented in the exit of amplifier, RL1 it interrupts immediately the line of loudspeakers preventing thus to reach in he. Parallel it provides a delay time of 3 seconds from the moment where the power supply will be applied. This delay protects the loudspeakers from undesirable bangs that are observed when open the supply switch.

TDA2030 Amp OTL 15W
Posted on Wednesday, November 17, 2010   •   Category: Amplifiers

Circuit of TDA2030 amp OTL 15W

HA1377 Bridge Amplifier BCL cap 17W (Car audio)
Posted on Wednesday, November 17, 2010   •   Category: Amplifiers

This is circuit Car audio Amplifier(Bridge Amplifier BCL) , It use IC HA1377, Supply Volt 12V-13V. Speaker 4 OHM. Nice Circuit and Easy to Build.