All posts on March, 2008
Posted on 29 Mar 2008
Author writes:”As an educational experiment, I decided to build a small temperature sensor, and data logger. Since I have little experience with direct Analog to Digital (A->D) converters, I decided to start out with a little more “meaty” hardware. I used a Basic Stamp II (BOE) BS2-IC microcontroller to capture temperature using a Sensirion Temperature and Humidity Sensor, and display using a 2×16 Serial Display.”[more]
Posted on 29 Mar 2008
This is a cheap DIY credit card reader project.The reader mechanism consists of magnetic head on a spring mechanism along with low level head signal amplifiers and data slicers. Three signal lines comming from the unit provide card presence, clock, and data.The data from the unit read by PIC12F675 in ASCII format then send to PC via RS232.[more]
Posted on 29 Mar 2008
This is a simple dynamically balanced vehicle.Williamson writes:The only really exotic component is the motor/gearbox: it is a high impedance motor with a 62:1 epicyclic gearbox and cost ?7. A cheaper option is to use a mabuchi solar motor without any gearbox at all, a walkman motor would also probably work although I haven’t tried it. Use a wheel just slightly
bigger than the motor body to maximise torque. One-wheel drive is important because the correcting force must be applied at the end of the dowel. If you use two wheel drive the sideways wobble of the mast puts all the weight on one wheel or the other and the vehicle spins about the axis of the mast. The undriven wheel provides sideways balance, like an outrigger, without exerting any steering force.[more]
Posted on 28 Mar 2008
You can build this FM receiver with just one MPF102 FET Transistor and a few of electronic components.This radio is sensitive enough to tune 20 stations across the FM band, some with volume high enough to drive a small PM speaker. The ability to tune 88.9 MHz and 89.1 MHz is testimony of its selectivity. The signal-to noise ratio rivals that of the better walkman type radios.In this exciting project, not only will you have a very unique one transistor FM receiver, but also be in-store for making home-made air-core coils. And even more than that, when you finish ‘your’ project, your journey has just started. With your now-working FM receiver, you can start experimenting with many wonderful things. [more]
Posted on 28 Mar 2008
This article shows you how to to build your own a simple ECG device & heart monitoring system. The signal from the body is being amplified, filtered to remove the noise, sampled by an Analog to Digital converter and then sent to your computer through RS232.This project use the famous instrumentation amplifiers device from Analog Devices(AD620).[more]
