Quadcopter of Harald Sattler

The top of the sNQ Shorty looks much tidier than its big brother, here the experience gained with the first work increases. The cables between the control unit and the LEDs and the motors are now laid on the underside of the circuit board and lead through the holes to the pads provided for this purpose.

sNQ Shorty – Quadcopter of Harald Sattler

“After initial flight tests I can confirm the function of the Mega328 with 16 MHz at 3.3 V operating voltage. Of course, one must be aware that the chip is operated outside its specification and no one can guarantee that the two chips and the ?C function are compatible with all possible conditions. It may well be that the shorty in the living room at 20 ° prima flies, then one opens the door and there comes cold air into the room, the copter simply crashes.”

Quadcopter of Harald Sattler

“With the sNQ Stretcho, we pushed the motors down as far as possible through the brackets, because this would dampen or even suppress vibrations due to the engine running, and disturbances of the IMU chip largely fall away. In the case of the sNQ Shorty, this can only be implemented to a limited extent, …”

Mikes Optical Timer Counter

“This page is the result of a lot of effort over the past couple years to develop a quality, inexpensive device to test shutters on the classic film cameras that I have been using…” .. Mike

Mikes Optical Timer Counter

Once built, this counter timer/device is easily adapted to a wide variety of applications, simply by construction of a new sensor. Although designed to be used with photo-transistors, this device can also use relays, transistors and many other kinds of electrical switches as a sensor.

Mikes Optical Timer Counter

Other Projects

Model Railroading, 3 Transistor Audio Preamp for a Dynamic Microphone

Configuration and control of this counter/timer is through a RS232 port. Cable configuration for a usual PC compatible would consist of a null modem cable, with a female connector on the timer/counter end of the cable. The correct cable for a PC or usb to serial adapter with a DB-9 interface is listed in the bill of materials.

delabs Page Digital Timers Counters and Clocks 

VK5JST Amateur Radio Ideas with Photos

The new Ham Project Pages are VHF/HF Aerial Analyser, A 600MHz Frequency Counter.  Then there is a an ESR Meter for Electrolytic Capacitors.

VK5JST Amateur Radio Ideas with Photos

With a two tone tester, a dummy load and an oscilloscope, a transmitter can be really put through its paces. Two tone testing consists of applying two clean non-harmonically related sine waves of approximately equal amplitude to the audio input of an SSB transmitter.

Simple Two Tone Oscillator

 

The sine waves are typically around 600 – 700Hz and 1800 – 2000Hz i.e. about 300Hz from either end of the audio pass band.

A Simple Two Tone Oscillator

This project was published in the September 2004 issue of the Australian magazine “Amateur Radio”.

Other Readworthy Pages

  • Easy PCB’s Made With Kitchen Appliances
  • How to Make a Q Meter
  • Making a High Current 13.8 VOLT Supply For SSB Transceivers
  • VK5MM’s excellent amateur radio homepage
  • Transformer Construction Details
  • Shortform Method of Designing Power Transformers

The photos at VK5JST Homepage are very educative and express the idea better than words. – delabs

Quasar Electronics – Hobby eStore

They specialise in online mail order electronics for industrial, educational and domestic applications. The company’s founder started selling electronic kits back in 1993 .

Quasar Electronics – Hobby eStore

Electronic Kits, Modules, Hobby Projects UK Superstore. A specialist retailer and manufacturer of electronic kits and modules with over 20 years experience.

Quasar Electronics - Hobby eStore

From electronic starter kits and project labs for kids to hi-fi quality valve audio amplifier kits for audiophiles and industrial controller boards for commercial applications

Official distributor stockists for Velleman, Cebek, Smart Electronics and Quasar Electronics. They also have power supplies, inverters, cables, leads, components, connectors,tools, soldering irons, multimeters, function generators and oscilloscopes.

Quasar Electronics Limited
PO Box 6935, BISHOPS STORTFORD, Hertfordshire CM23 4WP
UK – England & Wales

Tom Jennings – World Power Systems

“I make things, mostly technological, but don’t hold me to that, consistency is not a human virtue. Electronics and software, cast iron and plastics, microcontrollers in vintage automobiles, faux historical machinery that could (not) have been; finely crafted, rigorously rugged, reliable, most often.”

Tom Jennings – World Power Systems

The Model 01a (aka M01a) is a 3″ x 5.5″ self-contained controller board designed for embedded applications. It’s based around Microchip Inc’s in-circuit-programmable 14-bit PICs, and contains I/O expansion, a power supply and various goodies that I found useful in five years of using my previous controller board design.

WPS Model 01a Control Engine

WPS Model 01a Control Engine

The M01 board contains enough support hardware to pull off a lot of functionality. Before I get to handling common interface problems here’s a function-by-function description of the hardware. There’s some subtlety to some of the design that’s worth paying attention to.

Index of www.wps.com, by subject

Technical reference data; obsolete, obscure, hard to find, and sometimes just plain old; mostly things made or written by others.

G-switch timer – Vern Knowles

The timer is built using four small inexpensive CMOS integrated circuits. This allows it to run on just 3V from two small AAA batteries. U1 is a 74HC688 8-bit equality comparator. It compares the switch settings to the counter output and will set pin U1-19 low when they match. The actual counter is U2. It is a 74HC4060 14-stage binary ripple counter with built-in oscillator.

The G-switch itself uses a cantilevered metal bar that pivots down as the rocket accelerates upward. The metal bar actuates a small micro-switch that triggers a digital counter to begin the timing sequence. The timer is designed so that it will not start unless the micro-switch has been activated for a duration of at least 0.5 seconds.

G-switch timer - Vern Knowles

G-switch timer – Vern Knowles – The timer was built using a small prototyping circuit board and point-to-point wiring.

U3 is a 74HC74 D-type flip-flop that is used as part of the triggering logic. U3-12 will be low when the counter matches the switch settings. Consequently, on the next oscillator clock edge from U2-9 the flip-flop output at U3-9 will go low. This is the event that activates the 2N4403 transistor that fires the flash bulb.

Thaikits – Electronic Kits for Learning

A group of test engineers in Thailand who worked in an Electronic factory more than 12 years have started a small business to sell electronic projects and electronic kits worldwide in 2007.

CH012 Transistor Curve Tracer adapter XY Oscilloscopes 2 ranges Bias

Thaikits - Electronic Kits for Learning

Some interesting kits are HHO High Frequency PWM DC Motor Speed Controller 30A, CH018 Cycling Timer 1.5 -180 minutes ON-OFF 12VDC/30A Heavy Duty 110V/240VAC, CH024 ICL8038 Function Generator Sine Triagle Square wave 0.5Hz-100kHz.

Thaikits.com
5/16 Moo 18 ,Bueng Kham Phroi,Lam Luk Ka, Pathum Thani 12150, Thailand