LED Christmas tree – Learning Electronics

Letter from Chris of PyroElectro.com in 2013 – Happy Holidays!

Here’s a project I know your readers will love! It’s an all-digital-hardware LED Christmas tree we’re calling the Christmas Tree O’Digital Logic.

The tree itself is composed of 64 LEDs built into a spiral sitting on a piece of protoboard. Underneath, the controller uses shift registers and a 555 timer to create two modes of display: a predictable pattern and a random pattern. This should light up any desk or shelf and bring merriment to your readers!

LED Christmas tree - Learning Electronics

We’re also running a Kickstarter campaign to fund our second free online electronics course, “An Introduction To Digital Electronics.” We have just 4 days left to raise $2,124. If you would be so kind as to spread the word about our efforts, we’d be extremely grateful!

To build the tree, we’ll use 63 green LEDs and 1 red LED. Lots of wire will be needed to make the spiral + cone shape of LEDs from top to bottom. To build a random pulse generator, we’ll use some digital logic trickery with a 7404 hex inverter. A 555 timer will be used to drive 8 shift registers, which will control all 64 of the LEDs. Finally, a 4 bit timer should be thrown into the circuit in case we want to slow things down with a divider.

MadLab – Inventive electronic kits

Unique, hands-on electronics workshop for children and adults. In the workshop participants solder electronic components onto specially-designed circuit boards.

MadLab – Inventive electronic kits

MadLab has been made possible through the generous sponsorship and support of the Edinburgh International Science Festival, Zot Engineering and Microchip.

MadLab - Inventive electronic kits

A really useful tool for the budding electronics engineer – a digital frequency meter. New and improved version.

  • input signal range from about 15Hz to 8MHz
  • new feature – bypass switch for low-frequency TTL-level signals from 1Hz
  • internal accuracy +/-1Hz
  • 4 digits of displayed accuracy
  • input conditioning amplifier sensitive to 50mV

MadLab presents an absolute beginner’s guide to electronics. Following this short course will lead you from basic ideas about electronics right up to an understanding of how the simple MadLab kits actually work.

Experiments with the LM2575

The standard buck regulator circuit delivers a +5V output. This is a rather straightforward circuit and will operate with a wide spread of component values. Optimal values should be selected however to get minimal ripple, minimal noise to the power source, maximum efficiency etc. Note that the quiesent current is about 10 to 14mA.

Experiments with the LM2575

Here is a nice way of using this regulator, this can be used for CMOS opamps as you have a -5V too. That means a portable instrument may find this design useful.

The TI Datasheet Layout Guidelines

LM2575 Switching Regulator
LM2575 – Step-Down Adjustable Voltage Switching Regulator with Output Enable

 The Spirit of Hacking and Fixing, Giving back Life to Old Instruments.

Fluke 8050A LCD display replaced with LED seven-segment

“Recently I was able to cheaply buy a second hand Fluke 8050A made in the early eighties. It is a nice 4.5 desktop digit meter, but a typical problem seems to be that the LCD wears out and goes black. Replacement LCD displays are hard to find, not cheap and probably lead to similar problems in due time.”

Tesla Coils from Terry Blake

Nikola Tesla invented the Tesla Coil in the late 1800s. Here you will find some information and technologies related to that. HV is not safe and this is not a Hobby for Youngsters. Read to understand the dangers of High Voltage and Marvel at the phenomena.

Tesla Coils from Terry Blake

Multi-Mini Capacitors

The pulse-energy nature of the Tesla coil has long been a tough environment for the discharge capacitor. Coilers have built capacitors with glass bottles and salt-water, sheets of glass and aluminum foil, and more recently, polyethylene sheets, aluminum flashing, and mineral oil

Magnifier Tesla Coil

In a Classic Tesla coil, the magnetic coupling between L1 and L2 is around 20% (0.2).  Tesla realized this caused a lot of loss, and he abandoned the design in favor of a 3 coil system with a very high coupling (60%).

Tesla Coils from Terry Blake

D.C. Cox’s Cheesehead Teslathon, Ed Wingate’s RATCB Teslathon, The Geek Group’s Halloween Teslathon and many more.

MarS Board – Freescale ARM Cortex-A9

A super ARM DIY Platform. Measuring only 65.46mm by 102.04mm, the MarS Board is a low-cost highly-integrated controller board based on Freescale’s i.MX 6 Dual ARM Cortex-A9 application processor which encompasses a dual-core platform running up to 1 GHz with 1 MB of L2 cache and 64-bit DDR3 or 2-ch., 32-bit LPDDR2 support.

MarS Board – Freescale ARM Cortex-A9

MarS Board - Freescale ARM Cortex-A9

The MarS Board is a ready-to-run platform with ported Linux 3.0.15 or Android 4.0.4. Additionally, Embest provides the demo for uC/OS-II V2.92.05 for user experience. It is an ideal core processing component for your end devices based on a single hardware design

Features Include These too

  • MarS Board is a Multi-Display platform.
  • MarS Board is a Multi-Expansibility Platform
  • NEON SIMD media accelerator
  • HD class 1080p encode/decode video engine
  • 10M/100M/1Gbps Ethernet Interface

PIC Microcontroller with GSM

How would you let your PIC-Micro Board Interface with your Cell Phone (Network). These Cards and Designs will help your Embedded System to be Controlled or Monitored using a simple Wireless Device Networking.

PIC-GSM at Olimex 

Using PIC-GSM you can easily monitor and control your home from everywhere with your GSM cell phone. You can switch on and off relays remotely by SMS. You can monitor the status of your GPIOs or toggle them. You can establish a call to the GSM module and speak or listen on the audio channel of the board. You can monitor the temperature from several digital remote temperature sensors.

PIC-GSM at Olimex

SMS Transceiver for PIC (SMST4PIC)

SMS Transceiver for PIC (SMST4PIC) is a tool for sending SMS via a RS232 serial connection between a PIC and a mobile phone. It establish on the basis of a serial line connection a AT command based communication for sending SMS and SMS-based e-Mails.

GSM Monitoring and Control System

A simple GSM based monitoring and controlling system on a small board with a PIC processor holding a solid program able to control a various types of GSM modems and Cell phones.  Four inputs, one power output prepared for monitoring and controlling through SMS messages on your mobile phone.

OscilloScopes for the DIY Enthusiast

Here are some Hobby Scopes that might even be quite professional if you develop them further. They are virtual instruments. Making Scopes with tablets may be much more easy now.

The µSCOPE – A poorman’s oscilloscope
The oscilloscope is still one of the most important measurement tools of the electronic engineer. With the advent of the often very reasonably priced USB scopes, such an instrument is now within reach of every body.

OscilloScopes for the DIY Enthusiast

Digital oscilloscope – Build a simple Inexpensive digital oscilloscope. Single channel, about 100 MSPS. RS-232 based.

xoscope is a digital oscilloscope using input from a sound card orEsounD and/or a ProbeScope/osziFOX and will soon support Bitscopehardware. Includes 8 signal displays, variable time scale, math,memory, measurements, and file save/load.

xoscope – digital oscilloscope for Linux

MHZ100Q is a low cost FPGA-based high speed data acquisition system. Version 2 is a standalone board containing 2, 100MHz 8-bit A/D channels, preamp, 7th order elliptical antialiasing filters, and a Xilinx FPGA.

MHZ100Q – Open Source FPGA-based 100MHz A/D

A USB interface is implemented in the FPGA firmware. Power comes from the USB bus. Schematics, VHDL and Verilog source code, and signal capture and display software are available and being posted.