Jason Neals DIY Audio and Electronics

Dual Polarity Power Supply
Two versions of a dual polarity power supply with printed circuit board artwork. The supplies are built around the popular LM317 & 337 complementary voltage regulators which offer very high ripple rejection as well as short-circuit and thermal protection.

Jason Neals DIY Audio and Electronics

Microphone Preamplifier
A battery-powered microphone preamplifier and microphone wand for acoustic tests and recording. The preamplifier features 20dB of switchable gain and a clipping indicator,

Jason Neals DIY Audio and Electronics
An interesting website with many photos of electronic projects. There are not many projects but the description and photos and documentation are very useful for learning the art of circuit design.

Low Cost AM FM Stereo Receiver

This was a National Semiconductor Application Note, now TI. – Low Cost IC Stereo Receiver.

AN-147 Low Cost IC Stereo Receiver

Some Highlights

The LM3089 FM IF System does all the major functions necessary for FM processing, including a three stage amplifier/limiter and balanced product detector, as well as an audio preamplifier.

FM stereo demodulation is accomplished by the use of the LM1800 phase locked loop, thereby eliminating the need for external coils.

The AM function of the receiver is done completely with the LM3820 AM radio system. While designed for 3 section tuned superheterodyne application.

The LM382 dual preamplifier was selected for its minimum parts count and low noise capability.

Panel meters are employed in the FM system for both signal strength and center tuning, allowing for easy and accurate tuning. A directly driven LED offers immediate indication of FM stereo reception.

Low Cost AM FM Stereo Receiver

A single transistor tone control circuit was designed as the optimum cost/performance trade-off. The transistor is configured in a shunt-shunt feedback design, allowing gain variations between input functions.

The stereo power section, consisting of the LM378 dual audio amplifier, delivers 3W/channel with total harmonic distortion (THD) less than 1% and 4W/channel with THD less than 10%,

ELM – Electronic Lives Mfg

“My hobby has been a present occupation as it is because I liked electronics relatings since I was little. Railroad, anime, comic and TV game as well. As for programming in the hobby, because they are electronic handicraft” – Chan Japan

ELM – Electronic Lives Mfg

ELM - Electronic Lives Mfg

Chan has many projects for learning the use of Microcontrollers. even Instruments. You can even study about how to develop a PC Interface for electronic design you made. Then there are pages on Audio and Video Processing. See the LED Lantern and the Capacitance Meter too.

DC Servomotor Controller

This is an experiment on the closed loop DC servomotor control system (SMC). It will able to be used for practical use with/without some modifications.

Desktop Line Following Robot

In lines of the Japanese Tradition of Miniaturization, chan has built a tiny line following robot which can run on the desk, A toy that is one fifth the size of the line following robots, seen these days,

Analog Music and Sound Effect Synthesizer

Analogue Synthesizers you could build. Modular and Stand alone boxes. Simple schematics for the modules. The electronic analog basics to build your own synth.

Analog Four synthesizer by Elektron

“In 1997 a handful of students, who got together during a university course at the Chalmers University of Technology in Gothenburg, made a rough prototype of a synthesizer.”

“Elektron is an electronic musical instrument company, based in Gothenburg, Sweden, founded in 1998. Its products include the SID-based SidStation, the Machinedrum percussion synthesizer, the Monomachine synthesizer, the Octatrack performance sampler, and the Analog Four synthesizer.”

 Electron Analog Four 4 voice analog synthesizer

Analog oscillators, Opamp Filters, Ramps. Waveform Generators and Modulators. Generate Square, Sine, Sawtooth/Triangle waves with modulation and mixing.

Music From Outer Space
If you’re into electronics, can solder and trouble-shoot, they have many cool analog synthesizer projects.

SDIY aka Synthesizer Do It Yourself
“When I was a teenager, back in the seventies I became fascinated by those weird sounding machines with those huge panels full of blinking light bulbs and knobs.”

Analog Synthesizer Resources
“Many of these links are from the “Synth DIY” crowd, a community of electronic music enthusiasts who have collected together on the internet to share electronic design ideas and build synthesizer modules.”

Synthesizer Electronic Circuits – Discover Circuits
Hartley Oscillator, produce clean analog signals, paradoxical sounds, simple version of the DDS synth, Precision Frequency generator, Metronome, Beat Box, Tone Generators.

SynthBend – The Electronic Peasant

This is a Analogue Synthesizer Controller from The Peasant. It Aims to be an extremely versatile Musical Effects Equipment working with he “SynthCase System” which also can be found there.

SynthBend – The Electronic Peasant

SynthBend - The Electronic Peasant

Some of you may be aware of my Electronics Engineering community. A DIY question was asked by a young person …

“I wish to build a modular style analogue synthesizer . I was wondering if anyone had any relevant circuit diagrams for oscillators, filters or amps etc …..Im really interested in building good circuits but in my own design ?”.

This made me add some of the Analog Synth Enthusiast Sites in this blog. I also realized that this is a good starting point for young minds to learn analog design. If a student or hobby learner is enthusiastic about some idea, he gets the drive to learn the basics on his own.

When a person who is learning, or even a professional, is passionate about what he is doing; he achieves what is called as Resonance in that filed of activity. This is when Innovations Sparks, this is when an Invention Manifests. This is the beginning of R&D.

Getting back to The Peasant in his own words about this device he created …

“A classic control-voltage type keyboard and an Appendage ribbon controller would be the heart of the project, with many added features. A large quantity and variety of manual CV modulation controls, such as joysticks, potentiometers, and pressure sensors would also be included.”

GainClone Chipamp Audio Amplifier

Gainclone or chipamp is 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.

GainClone Chipamp Audio Amplifier

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.

GainClone Amplifier Rod Elliott (ESP)

“The amp is based on the Project 19 PCB, so uses a pair of LM3876 (or LM3886) power opamps, run from a ±35V supply. ………..The power supply is conventional in almost all respects. I used a 160VA transformer, a 400V 35A bridge rectifier, and a total of 20,000uF per supply rail – 4 x 10,000uF caps in all.”

GainClone Chipamp Audio Amplifier

“The Gainclone amplifier has proved very popular with hobbyists since construction is straightforward and the resulting amplifier has an impressive performance specification.

A Gainclone for the PC Age

Most designs discussed online are aimed at audiophile applications. Here is a design for connection the a PC. It powers up and down with the PC and audio input can optionally be taken over USB.”

Gainclone Monoblocks

“But it was the Gaincard that caught the imagination of audio diy-ers around the world and before long, copies of the Gaincard were appearing on internet sites and discussion forums. The Gainclone was born!”

incise.org: gainclone

“I had previously planned to build a small stereo amp using the amp6 kit from 41hz.com. After deciding I wanted a bit more power, I did some research and am now going to build a so-called gainclone amp based on the LM3886 chip.”

“First, check out this 3-channel buffer amp Darcy made! It uses the chipamp.com LM3886 amp boards! Feel free to send pictures of your amp and we’ll show them off for you.”

Flashing Mains Neon Lamp

Here is a Neon Flasher circuit (untested) for a user request at Circuits FAQ. This can be built into a switchboard or a gadget for indicating Live Power.

D1-C1 form a simple half-wave rectifier, The Cap charges to peak voltage and can store charge for a long time if there is no bleeder. So while building it take extra care. This forms a DC supply across C1. C1 is a Plastic High-voltage cap, IN4007 has a 1KV rating, so it is ok for 230V rectifier.

R1 Charges C2 and when C2 reaches 60-80V depending on Neon, the neon breaksdown. C2 Discharges, Neon Recovers, The C2 starts charging again and so on and on. It Oscillates, probably in a Ramp Waveform. But do not use your Scope on this, you will regret it a lot. This is a live circuit and needs a special probe.

“Oh, i will put the probe it in 10M mode” will not do. The ground clip of the probe goes to Electrical Earth which is ‘connected’ to Neutral in the mains wiring. So you put the earth crocodile clip on the live point. There will be flashes and fireworks. So you need to isolate both terminals of scope. Please use your costly equipment with great care.

For the 1 Meg use two 470K in Series for 230V AC, that is safer. The circuit is live, so take precautions. The 0.47 Micro Farad can be increased if you want a slow flash. If the Mains 50/60 Hz Flicker is too much, the 1 uF can be made 2 uF, or use 4 – 1N4007 as a bridge rectifier.

From Schematics of delabs

User Feedback –

R1 of 4.7M and C2 of 0.47uF Works well at 230V AC. Try your own Combination. Less than 1M may damage Neon.