This is a very simple circuit to interface a current loop sensor to an input which is designed for a voltage, such as that from a standard potentiometer. This page is technical so that interested persons can build the circuit themselves, but 4QD can also....

Here is an interesting circuit for a magnetic proximity switch which can be used in various applications. The magnetic proximity switch circuit, in principle, consists of a reed switch at its heart. When a magnet is brought in the vicinity of the sensor....

The low-cost circuit in Figure 1 allows you to track four remote temperatures with thermistor sensors through the parallel port on your PC. This four-zone thermometer instrument has a temperature range of 40 to +90°C and a resolution of better than ±1°C. You....

This is the lowest cost dialing alarm on the market and shows what can be done with an 8-pin microcontroller. The complete circuit is shown below. You cannot see all the features of this project by looking at the circuit - most of them are contained in the....

Pin 3 defines the Display type: Common Cathode or Common Anode. Connect this pin to GROUND if you are using common cathode 7-segment led displays. To use common anode displays, connect it to VCC (positive) Pin 4 is the signal input, you can use optical....

The circuit is drawn for measurement of acceleration from 1000 mg until + 1000 mg. It can be placed in kantra'n the car and be supplied from the sheath of electric lighter. The circuit includes one indicative LED and a screen LCD. The measurement of....

This circuit is intended to control a heating system or central heating plan, keeping constant indoor temperature in spite of wide range changes in the outdoor one. Two sensors are needed: one placed outdoors, in order to sense the external temperature; the....

Intelligently modifying the motor-drive commands to a robot can give you control finesse during competitions. Moving a joystick hard right, for example, might have different effects, depending on the robot`s speed and direction. Software running on an....

There are several websites documenting the original Furby circuit board. I decided to replace the original circuit entirely and replace it with a PIC based controller. The mechanism of the Furby itself was designed around micro- controllers. It has one....

Many noncontact temperature-measurement systems use infrared sensors, such as thermopiles, which can detect small amounts of heat radiation. Biomedical thermometers that measure the temperature of an ear or a temple use noncontact temperature measurement, as....