Simple power supply for large breadboards

Most breadboards are not equipped with a power supply circuit. Every electronic enthusiast uses a breadboard since they are a fundamental tool to develop in a fast and easy way. Some problems arise when we need to work with devices not powered from the USB port or that need other supply voltages than 5V, so I decided to add a simple power supply to my large breadboard.

bbsupply_main

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2SC5200 & 2SA1943 output power stage

Every audio amplifier is made basically of three blocks, each one with different purposes:

  1. Voltage Amplifier – it receives the input signal with high impedance (tipically 47kohm) and amplifies it so that can drive the driver stage
  2. Driver Stage – is places between Voltage Amplifier and Output Stage and adapt and sometime “processes” the signal so that can drive the output stage
  3. Output Stage – is the final block in charge of deliver high currents, so that the amplifier can handle low-resistance loads such as a speaker

out_pwr_st_diag

The project that I’m about to present is an output power stage, capable to handle more than 500w if mounted on a suitable heatsink.

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LM3886 Gainclone Boosted!

Gainclone or chipamp is a term commonly used to describe a type of audio amplifier made by do-it-yourselfers, or individuals interested in DIY audio. It is a design based on high-power integrated circuits, particularly the National Semiconductor Overture series. The Gainclone is probably the most commonly built and well-known amplifier project amongst hobbyists. It is simple to build and involves only a few readily accessible, inexpensive parts. As an amplifier it is highly regarded by many in the DIY community. (from wikipedia http://en.wikipedia.org/wiki/Gainclone)

No one can describe the gainclone’s philosophy better than this wikipedia page!

Tha gainclone is an easy-to-built, cheap, hifi quality, simple amplifier made with few components. I’ve decided to create a gainclone version myself, doubling the output power and using the idea from an old application note from National Semiconductor, talking about the parallel amplifier PA100.

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Schumann Resonator

The Schumann resonances (SR) are a set of spectrum peaks in the extremely low frequency (ELF) portion of the Earth‘s electromagnetic field spectrum. Schumann resonances are global electromagnetic resonances, excited by lightning discharges in the cavity formed by the Earth’s surface and the ionosphere.

(from Wikipedia http://en.wikipedia.org/wiki/Schumann_resonances)

Schumann resonances are claimed to provide equilibrium between people and Earth, since the main frequency (7.83Hz) has a wavelength of 38000Km (about the circumference of the Earth). Most of scientific community argued that a body small like the human one can’t obtain advantages from this frequency. Despite of this, some audiophiles (in which I also agree) says that when in presence of a Schumann resonance the music listening is more relaxed.

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