I worked on developing a digital frostpoint hygrometer for measuring water vapor at NOAA. Using an old analog instrument as a reference, I created this new hygrometer using AVR microcontrollers and other digital electronics. I laid out the circuit board using Altium DXP, had the PCBs fabricated through various companies, and soldered all the parts
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onto each board. I also wrote both the embedded C microcontroller code and C+ control program for the hygrometers. The embedded software handles all of the logic, communication protocols, and data processing on the circuit board. The control program displays and plots the hygrometer data, and allows for certain calibrations to be set. Using Altium DXP, I created the schematic for the frostpoint hygrometer. It centers around an Atmel AVR microcontroller (with decoupling capacitors, a reset pullup resistor, a crystal oscillator, a status LED, and a UART/RS232 header). Many parts are connected through the SPI bus and other IO pins, including an ADC, pressure transducer, and SD card connector. I laid out this printed circuit board from the hygrometer schematic. Copper traces connect various ICs, using vias to change layers when necessary. Designators and layout information are silkscreened on the top layer for reference. Companies like Imagineering can use this layout to fabricate the actual PCBs. This is the finished hygrometer board. I soldered all parts on the PCB using a regular soldering iron. As production increases, we will move to a more efficient means of fabrication (hot air reflow, or using a separate company that has a pick and place machine). These instruments are now used as the standard on our balloon flights to measure water vapor, giving accurate data even in the upper atmosphere (with incredibly low water...
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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