Hobby Projects - Insulation tester, LED Circuits, Meters.

Thursday, August 25, 2011

8051 Single Board Computer

New Microprocessor learning board demonstrates exemplary design of 8-bit single board computer. More peripheral and easy to adapt to be a dedicated controller.

8051 Microcontroller Kit

8051 kit using 7-segment display and hex key monitor. The design is simple, small number of components and cheap. The size is compact, 5.3x5.7 inches. The keypad is ergo design for young students. The kit is 8051 based microcontroller. So many chip makers produce the 8051 core microcontroller. The kit is available for both preassembled and kit form.

 8051 Microcontroller Kit

8051 Single Board Computer

The new 8051SBC features;
  • CPU: Any 8051 compatible with 40-pin DIP package @11.0592MHz
  • MEMORY: 27C256, 32kB EPROM for monitor program
  • 62256, 32KB SRAM for both code and data space
  • I/O: direct cpu bus interface 2x16 line LCD
  • MEMORY and I/O Decoder: GAL16V8D
  • EEPROM: 24LC256, 32KB serial eeprom
  • RTC: Real-time clock, DS1307 with +3V Lithium backup
  • ADC: LTC1298, SPI interface 2-channel 12-bit Analog-to-Digital Converter
  • I/O pins: P1,P3 of 8051 cpu, 16-bit I/O port
  • Keypad and DIPSW: 4-bit keypad and 4-bit DIP switch
  • RS232 Level Converter: MAX232
  • RS485: 75176 differential transceiver
  • Serial Interface: 9600 8n1
  • Monitor Program: Modified PAULMON2 including new commands
delabs Notes -
 
This is an Educational Masterpiece, with more Relevance to Asian Students. I took my first steps with 8085, Z80 and later 8749. Then the 80C51. If you start writing code for 8080, you will want features which will come in 8749 and when you study 8749 and think of enhancements 80C51 will pop out as if they read your mind.

Once you work with these, then you can use all the new uC and uP easily. It is better you write code with as less EPROM or Flash as possible. This will help you make quality code. The smaller the code the more real time your firmware and lesser bugs.

Wednesday, August 24, 2011

Stereo Audio Music Players

40 Watts Hi-Fi Music System - Stereo Music player with Tuner, 1986, LED VU meter and Analog VU meter.

SAN 20

This was done as repairing home electronics was my hobby in school days, I learnt by building Amplifiers based only on transistors from the Old Philips Circuits and Books. The above one is TDA2020 20 Watts Per Channel, with LED input level meter and moving-coil output meters.

It would have a 5 pin din input and RCA speaker output, input for phono, tape, etc. The Speakers had a woofer, tweeter and midrange with passive crossover network.

SAN 20 Speakers

Stereo Adapter for Portable Music Player

Low Cost Stereo Adapter 20 Watts for Portable Music Player 1984, Bass Treble and Presence.

Portable Music Player

This was a TB810 based 10+10 Watts Stereo Amplifier with LM381 or 2 Preamplifier, The portable player docks in a wooden cabinet. There was no IR, Wi-Fi or Bluetooth in those days, so the device would interface with amp thru a stereo ear-phone socket-jack system with a shielded cable. Bass, treble and Presence as per an old phillps audio amp book.

FreePCB - PCB editor

FreePCB - PCB editor

FreePCB is a free, open-source PCB editor for Microsoft Windows, released under the GNU General Public License. It was designed to be easy to learn and easy to use, yet capable of professional-quality work. It does not have a built-in autorouter, but it can use the FreeRoute web-based autorouter at freerouting.net. Some of its features are:

  • 1 to 8 copper layers
  • Board size up to 60 inches by 60 inches
  • Uses English or metric units (i.e. mils or mm) for most functions.
  • Footprint libraries courtesy of Ivex Design International Inc.
  • Copper fill areas
  • Footprint Wizard and Footprint Editor for creating or modifying footprints
  • Imports and exports PADS-PCB netlists
  • Exports extended Gerber files (RS274X) and Excellon drill files
  • Design rule checker
  • Autosave

Example - Logic Analyzer: This is an open-source logic analyzer called MiniLA contributed by Bob Grieb of the User Forum. The image on right is the Logic Analyzer PCB.

miniLA - mini Logic Analyzer

Some Features:

  • Up to 32 channels
  • 128 Kb of memory for each channel
  • Sampling rate up to 100 MHz (timebase in 1-2-5 sequence)
  • Input levels compatible with 3.3V and 5V logic
  • Selectable pretrigger/posttrigger buffer size in 8K step

Tuesday, August 23, 2011

PIC Project by Myke Predko

"The application itself consists of the 16F84 PICMicro (with power, reset and clocking 'core') with two LEDs and a button. One of the LEDs is lit by the PICMicro while the other is lit when the button is pressed. "
PIC Project by Myke Predko
 


The Experience he Gained -

"There is one point to make about the layout that you should always keep in mind when developing a circuit with a microcontroller or other programmable device; you should always design the circuit in such a way that the chip can be pulled easily. This means that there should be space at either end for prying the chip up out of its socket or, as I like to do, slide a small screwdriver underneath the PICMicro and "pop" it up simply by twisting it. I know a lot of people that end up cursing themselves because they've forgotten to remember this basic operation"


The Experience of the remote Hobbyist is very important for a Kit Maker or Gadget Maker. We tend to feel .."everybody thinks like me". Each person has his own faculties, tools and experience. Most importantly - the method of teaching which has to adapt to each student. Hence it is important to have a spread of different things and methods, for a enthusiast to choose from. - delabs

The Micro Stop - RS232 and microcontroller schematics and C code, a lot is free! RS232 DVM-001 Voltage Input Board in Kit Form or Fully Assembled and Tested


RS232 Voltmeter PIC Based

123 PIC MCU Experiments for the Evil Genius by Myke Predko

Thursday, August 18, 2011

Why Wi-Fi gaining over RJ45

This would be nice on Instructables, The speed of data transfer on a wired connection depends on Cable, Connector and the Crimping.

Ethernet over Coax (EoC) co-axial cable. Optical and Gigabit Ethernet over Optic Fibers. Copper twisted pair and others are other means of Digital Data Transfer over Ethernet.

Wi-Fi and WiMax helps freeing the user from wires.

Building a RJ-45 Ethernet cable of a specific length

RJ-45 connectors and coloured caps; the latter helps to protect the ethernet connector as well as they differentiate the cables in the muddle of cables a network can produce!

Down flat... and in the right ordre to be manipulated; from left to right:

white/orange, orange, white/green, blue, white/blue, green, white/brown, brown

Tuesday, August 16, 2011

Supercap and White LED and Energy Harvesters

This is a educative and simple example to help learn about supercaps and white LED. It will also help you understand component behavior. If you are learning electronics, try this one out.

The goldcap-Dynamo Lamp idea is a DIY Tutorial by Kainka on Electrical Energy Harvesting. What may be this EH Thing ?

http://www.b-kainka.de/bast482.jpg

Energy harvesting (also known as power harvesting or energy scavenging) is the process by which energy is derived from external sources (e.g., solar power, thermal energy, wind energy, salinity gradients, and kinetic energy), captured, and stored for small, wireless autonomous devices, like those used in wearable electronics and wireless sensor networks. - EH at Wikipedia
 
Then the Cycle Dynamo may not be the ideal choice for furthering this research. The reason being, this is quite a powerful source of energy, especially when going downhill!

We need a more fussy source of Electricity. Like the waves of the sea, that could splash onto Large plates of Springy Beryllium Copper Cantilevers, which moves an Array of Magnets in coils (Reverse of Solenoids). This gives Random Spurts of High Energy Pulses which have to be Harvested.

That is for you to dare and do ........ Now let me give some things you can read, before you start this epic Adventure...
Now Move ! There is so much Abundant Energy to be Harvested. You can Even Setup a Roadside Electric Trike Recharging Station.
Gomier Electric Tricycle
Gomier Electric Tricycle

We need more contests, An LED Lighting Contest and a Sponsored Elekrik Vehicle (Non-Car) Super-Contest.

Monday, August 15, 2011

DIY Electronics Section of Beis.de

Here you will find Audio Oriented projects, many in the German Language. There is one - Converting Analog into Digital (IIR) Filters which is useful for Mixed Design students. Then there is a FPGA-Based Digital Audio Peak Level and Correlation Meter with many features. The Hi-Fi Audiophile will like the Tools - Audio Preamplifier, Weighting Filter Set and Universal Filter.

DIY Electronics Section of Beis.de

24 Bit / 192 kHz Audio ADC and DAC AD24QS and DA24QS</p> <p>

24 Bit / 192 kHz Audio ADC and DAC AD24QS and DA24QS

"It is very well known what kind of deviations from the original signal a human ear is able to hear (e.g. distortion, frequency
response, noise etc.) and also in which amount and under which circumstances this is the case. All these deviations from the original
signal are measurable with a precision and sensitivity far, far superior to the human ear...."

An Introduction to Delta Sigma Converters

Delta sigma converters are different from other converters. Note that I do not make a difference between analogue-to-digital (ADC) and digital-to-analogue converters (DAC). Both are very similar and what is realized in one of them using analogue signal processing circuitry is implemented in the other one using digital signal processing and vice versa. I will explain the delta sigma technique with the analogue-to-analogue delta sigma converter as the first object.