background preloader

Electronics 7

Facebook Twitter

MySensors - Store. Here you will find verified hardware for your sensor project.

MySensors - Store

From reliable eBay and AliExpress sellers offering really low prices. Almost all recommended items have free shipping. To keep the low prices, shipment is often made from Asia and the usual delivery time is 2-4 weeks depending on your location. We will go through this product list from time to time and update the selected items.

If you are having any problems with the recommended sellers and/or products, please let us know by sending an email to Electronics Index. Battery amp-hour, watt-hour and C rating tutorial. Measuring Battery Voltage with an ADC > Measuring Battery Voltage with an ADC How to measure the voltage on a power source that is greater than the maximum rating of your ADC If you are using a battery powered device, it's often useful to be able to measure the current voltage level on the battery to estimate how much stored energy is left.

Measuring Battery Voltage with an ADC >

You may wish to alert the user if the charge level drops below a certain level, for example, or automatically shut the device off beyond a certain lower threshold. On the other end of the scale, if you are charging the battery, you may wish to cut off the charging process once a certain upper limit is reached. These measurements would all be relatively easy if your battery supply never exceeded 3.3V, for example, but many batteries do indeed exceed 3.3V, such as Lithium Polymer cells that typically go up to 4.2V when fully charged -- much too high to safely connect to an ADC line on your MCU. Basic Voltage Divider Calculating the Relationship Between the Input and Output Voltage.

Hacking. RotaryEncoders. ALPS STEC12E07 Encoder A rotary or "shaft" encoder is an angular measuring device.


It is used to precisely measure rotation of motors or to create wheel controllers (knobs) that can turn infinitely (with no end stop like a potentiometer has). Some of them are also equipped with a pushbutton when you press on the axis (like the ones used for navigation on many music controllers). IMAX B6 50W 5A Charger/Discharger 1-6 Cells (GENUINE) The IMAX B6 is a very advanced charger, able to charge, balance and discharge LiIon, LiPoly, LiFe (A123), NiCd and NiMH batteries.

IMAX B6 50W 5A Charger/Discharger 1-6 Cells (GENUINE)

It is microprocessor controlled just like all the best chargers and will balance the indervidual cells in you Li-XX batteries. It will charge from 0.1 to 5.0A and is capable of charging packs up to 6S packs. It features input voltage protection so as not to flatten your car battery at the field and will also storage charge you packs for when you are not using them. You can power it with any power supply delivering from 11~18V so it is very flexible. This is a GENUINE iMax B6.If you would like a lower priced 6S charger please check our website for other brands.

Web Seminars. HAM RADIO ACTIVITY on Pinterest. Arduino. Starter motor. AVRs. Programmable DC Backup Power Supply. The uninterruptible power supply was once a standard fixture in the small office/home office as a hedge against losing work when the electrons stop flowing from your AC outlet.

Programmable DC Backup Power Supply

Somewhat in decline as computing hardware shifts away from dedicated PCs toward tablets, phones and laptops, the UPS still has a lot of SOHO utility, and off-the-shelf AC units are easy to find. But if your needs run more to keeping the electrons flowing in one direction, then you might want to look at [Kedar Nimbalkar]’s programmable DC backup power system. Built inside a recycled ATX power supply case, [Kedar]’s project is heavy on off-the-shelf components, like a laptop power supply for juice, a buck converter to charge the 12 volt sealed lead acid battery, and a boost converter to raise the output to 19.6 volts.

An Arduino and an optoisolator are in charge of controlling the charging cycle and switching the UPS from charging the battery to using it when mains voltage drops. Solar panel , Buy solar panel Direct from China Manufacturers and Suppliers. Find Made In China solar panel Products - Electronics2. Electrical Engineering. Z0UxR.png (PNG Image, 956 × 570 pixels) IoT. Development Tools. References. Chapter 6: Diode applications (Power supplies, voltage regulators & limiters) [Analog Devices Wiki] 6.1 Rectifier A rectifier is an electrical device that converts alternating current (AC) to direct current (DC), a process known as rectification.

Chapter 6: Diode applications (Power supplies, voltage regulators & limiters) [Analog Devices Wiki]

Rectifiers have many uses including as components of power supplies and as amplitude modulation detectors (envelope detectors) of radio signals. Raspberry Pi. Fractal HF antenna: science or fiction ? When I first got interested in Amateur Radio, I quickly realized that antennas were one of the most important components in an efficient radio station.

Fractal HF antenna: science or fiction ?

One of the most popular type of HF antenna used today is the typical dipole antenna. Invented over 125 years by a German physicist, this antenna is simply two oppositely charged wires and stretched in opposite directions (or poles). These two wires, when energized create an electro-magnetic field that in rapid succession will generate waves, radio waves. The length of the wires needs to be at, or very close to the desired resonating frequency to be able to efficiently transmit and receive the radio wave. Wireless Sensor Network. Frequency counter with PIC and 4- to 5-digit LED display. This document describes the construction of small frequency counter with a cheap PIC microcontroller and a few seven-segment LED digits.

Frequency counter with PIC and 4- to 5-digit LED display

The main features of the frequency counter are: frequency range 1 Hz ... 50 MHz (prototype worked up to 60 MHz but this exceeds the PIC's timing specifications) four or five digits resolution (display for example kHz, MHz, or xx.xx MHz); or 6 digits with F8FII's modification automatic range switching with different gate times optional addition or subtraction of a frequency offset (programmable) optional preamplifier for the input signal can be built on a single-sided 'breadboard-style' circuit board firmware available for common-cathode as well as commom-anode displays very low component count: a PIC 16F628, 4 or 5 7-segment LED displays, a 4- or 20-MHz crystal and a few resistors, optionally one transistor and a few diodes to drive the 5th digit, optionally one other transistor for the preamplifier.

Contents of this document: V. Electronics. MQTT Commander - an Android Application. - Wed Jul 08, 2015 7:43 am#22763 This simple App can switch a light bulb or any appliance from anywhere in the world, using an Android smartphone.

MQTT Commander - an Android Application

Electrical Engineering. How CMOS Works: MOSFETs, JFETs, IGFETS and More. CMOS opened the door for many if not most of the properties needed for today’s highly integrated circuits and low power portable and mobile devices.

How CMOS Works: MOSFETs, JFETs, IGFETS and More

This really couldn’t happen until the speeds and current drive capabilities of CMOS caught up to the other technologies, but catch up they did. Nowadays CMOS Small Scale Integration (SSI) logic families, I.E. the gates used in external logic, offer very fast speeds and high current drive capability as well as supporting the low voltages found in modern designs. Likewise the Very Large Scale Integration (VLSI) designs, or Very Very Large Scale if you like counting the letter V when talking, are possible due to low power dissipation as well as other factors. How CMOS is Designed. Visualizing RF Standing Waves. Standing waves are one of those topics that lots of people have a working knowledge of, but few seem to really grasp.

A Ham radio operator will tell you all about the standing wave ratio (SWR) of his antenna, and he may even have a meter in the shack to measure it. He’ll know that a 1.1 to 1 SWR is a good thing, but 2 to 1 is not so good. Ask him to explain exactly what a standing wave is, though, and chances are good that hands will be waved. $40 Antenna Analyzer with Arduino and AD9850. Prize Entry: PICs and Arduinos, Cats and Dogs Living Together. Half of our little corner of the Internet complains about the Arduino, how the pin headers of the Arduino standard don’t make any sense, how the Arduino IDE is rubbish, gives well-reasoned arguments why the Arduino language is hindering the next generation of embedded programmers, and laments the fact that everything is commoditized into Arduino-compatible packages. The other half of our little corner of the Internet uses Microchip PICs. Hacklet 69 – Morse Code Projects. With over 160 years of history under its belt, Morse code is by far the oldest digital signaling system known to man.

Originally developed for telegraph systems, [Samuel Morse’s] code has been sent over wires, via radio, and even with flashes of light. Hackers, makers and engineers have been working with Morse code throughout history. For many years, simple code keys and practice oscillators were the “hello world” of hobby electronics. DEF CON: The Proxy for ProxyHam. Two weeks ago, news broke of an incredible abuse of power from the National Security Agency. A DEF CON talk was cancelled, and speculation raged that information was not free. This was the ProxyHam, a device that puts you miles away from any agency hunting down your IP address.

Of course, as with just about every DEF CON talk picked up by the press, ProxyHam is an ill-conceived, terrible idea. You can replicate it with parts bought from newegg, and despite using a highly directional antenna the FCC – or any other government agency – can still track you down. In lieu of a talk on using off-the-shelf networking hardware in the way it was intended, [Dave Maynor] and [Robert Graham] of Errata Security gave a talk at DEF CON that is the proxy to the ProxyHam. Self Built Power Meter Uses Dual Sense Transformers. Self Built Power Meter Uses Dual Sense Transformers. Top 40 Arduino Projects of the Web. Raspberry. Proyecto 1. Projectos. The Repeater Builder's Technical Information Page™ ARDUINO HF Anten Analizörü. Untitled-1.png (PNG Image, 1046 × 785 pixels) - Scaled (97%)

Arduino SWR-Power Metre. OH2NLT_bridge.pdf. Jagracar/grafica. ARDUINO HF Anten Analizörü. HF_bridge_diode_FWDvoltage_compensated.pdf. ARDUINO PROJECTS. Hack N Mod - Amazingly Cool Hacks, Mods, and DIY Projects. General Electronics. Environmental Physicians Issue Stern Warning on Biological and Health Effects from Electromagnetic Field Exposures. The American Academy of Environmental Medicine (AAEM) today issued a position paper on “Electromagnetic and Radiofrequency Fields Effect on Human Health”, including wireless technologies and smart meters. Today’s report on electromagnetic fields takes a strong stand that society must acknowledge the biological effects of electromagnetic fields, educate the population about the risks from wireless technologies, and develop safer technologies.

The group, AAEM, is an international association of physicians and professionals that has been dedicated to expanding the knowledge of human health in relationship to the environment since 1965. ALERT: AAEM Releases Recommendations EMF and RF Exposures (7/12/12) These recommendations by AAEM, just released on 7/12/12, will take the world by storm. AAEM recommends that patients with a broad range of medical conditions avoid sources of EMF and RF radiation, especially smart meters on patients’ homes and on neighbors’ homes, nearby. Radio Frequency Safety. ARDUINO PROJECTS. An Accurate Power Meter For QRP Ops by

RF Power Meter by QRP Wattmeter by Power and power measuring techniques by OZ2CPU digital wattmeter by KD1JV Digital SWR / Power Meter by RF Power Detector. K6BEZ Antenna Analyser - Yahoo Groups. Sweeper: An Arduino SWR Scanner. Bill of Materials Arduino UNO board and development cable, standard A to B typeMain Prototyping board, Twin Industries 4” x 5” 8000- Detector prototyping Arduino ProtoShield Keypad Shield v2.0 RF synthesizer regulator mount BNC SWR Bridge Parts. Antenna Analyser Project. Antenna Analyser Project. View topic - SWR Sweeper PC Board version 1.0. Pa0 fbk ham page. SWR Bridge. Bandplan.jpg (JPEG Image, 1167 × 900 pixels) - Scaled (87%) Arduino. Raspberry pi. Digital Wattmeter - 300nW to 30W by

PWR/SWR. Scrap To Power. Wavenode SWR and RF wattmeter with computer graphics and DC power monitoring. Complete with SWR protection and high power remote sensor. Also includes audio and voice announcement of RF power and SWR. Simple RF Current Probes. Amateur Radio II. Amateur Radio III. Amateur Radio I. Tesla Coil Design, Construction and Operation Guide. How to Understand, Present and Invent Electronic Circuits.

NIKOLA TESLA'S WIRELESS WORK. Electronics. Scratch for Arduino Makes Programing the Arduino More Visual. Creating a Mini Maker Space.