Electronics, Radio & antennas

1PPS distribution circuit

1PPS is a great way to synchronize multiple devices and measure time intervals. A typical source of the 1PPS is a GPS receiver. This clock is disciplined by GPS atomic clock and has a reasonable precision. GPS receiver 1PPS output should have enough loading capability, but it’s a good idea to use a buffer. Especially when voltage level translation is…

Continue Reading

Electronics

Compact and powerful DC driver using IRS2104

A few years ago, I wrote about the powerful DC motor driver based on IR2110. This construction appeared to be quite popular. This time I want to describe a much compact and simpler (but still very powerful) solution with IRS2104. This device can be used to control any power-hungry DC load like DC motors, heaters, and so on.

Electronics, Linux system development, Radio & antennas, Radioastronomy, Software

Satellite LNB controller with GUI interface

Satellite LNB are quite cheap and easy to get devices. There are different models for different bands (C, Ku, and Ka) with different characteristics like SNR, noise figure, etc. Typically those devices are used with TV Set-top boxes. More interesting is that LNB can be easily connected to an SDR receiver. LNB is a simple frequency down-converter with an output…

Continue Reading

Linux kernel, Software

Linux block device driver

My article about character devices is quite popular, so I decided to write something about another big class of devices in Linux – block devices. This type of device is used to access various storage hardware types – hard disks, SSD, etc. Here I want to describe blk-mq based devices in modern (>= 5.0) Linux kernels and a previous type…

Continue Reading