Electronics

Isolated USB to RS485 adapter

RS485 is a standard for use in serial communications systems. Electrical signaling is balanced, and multipoint systems are supported. This communication standard is used in a wide range of computer and automation systems. RS-485 is used as the physical layer underlying many standard and proprietary automation protocols used to implement Industrial Control Systems, including the most common versions of Modbus…

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Allsky camera, Astro tools, Electronics

Autonomous Allsky camera with Raspberry PI. Part 1: overview.

Allsky (or weather) camera is one of the most important parts of the modern observatory. It’s very important to monitor sky conditions during night observations, especially when the observatory is remote controlled or should be fully automatic. Different vendors provide different solutions. But all they are share the same problems: very high prices, lack of autonomy (PC is required) and…

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Allsky camera, Electronics, Linux system development

Connecting HTU21D temperature/humidity sensor to the Raspberry PI using simple C i2c interface

Previously in my projects, I’m always used well-known DHT22 (AM2302) temperature/humidity sensors. But I found that these sensors are not very stable and subject to hung. In my case, this device is worked for about two weeks and then stops responding until power rebooted. This is absolutely unacceptable on some distant and autonomous devices. After some googling, I found that…

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Astro tools, Electronics

Isolated eqmod adapter for the telescope control

There are popular and quite cheap amateur telescope mounts from different vendors: Sky-Watcher, Celestron, and so on. Most of that mounts contain motors and some controller schematic. Users can control these devices in different ways. One way is to use the mount’s hand controller, other way is connect to computer and use some software to control and guide the telescope.…

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