This 1-Wire MicroLAN [1] uses a capacitor and diode half-wave rectifier to provide parasitic power from the data line for the station's various sensors and to transfer data (see Figure 1). Each sensor has a unique serial number that identifies it to the bus. The station is controlled by a PC or microprocessor executing Touch Memory Executive (TMEX) software. Data transfers are half-duplex and bit sequential over a single twisted pair using short and long time slots to encode the binary 1s and 0s.
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Wind Direction
Magnetically activated reed switches were selected as the wind sensors for several reasons. They do not require power to operate. Because they are neither motion nor rate dependent, they can measure static conditions. They do not require signal conditioning. And they have a very high impedance in the open state and negligible impedance (150 m) when closed.
The basic weather station measures wind speed and direction, ambient temperature, and rainfall totals (see Figure 2). The package can be augmented with humidity, barometric pressure, and other weather sensors simply by connecting the sensor to the cable at the desired position and adding the appropriate software. Another option is to connect several weather stations to the same 1-Wire communication link for cost-effective measurement of laminar air flow patterns and other climatic parameters.
Interestingly, reed switches are normally rated as failed or end-of-life when the on resistance of the switch reaches 1 or 2 when operated at rated power level. A reed switch can operate over 100 million or more cycles at 50 V/100 mA levels or higher before failure. 1-Wire devices, which run at 5 V/4 mA, present almost no load, however, and can work with on resistance values of up to 100 . The functional lifetime of a reed switch in a 1-Wire environment such as the weather station is therefore much greater. Ongoing tests on the weather station show no degradation...
This project fits more for custom made battery casing that can have more space to hide things inside. This switch with few alterations can be used for any other project as well but is designed based on e-bike needs! This project use a clever functionality of....
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is....
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to....
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This....
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the....
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound,....
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the....
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power....
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower.....
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