Category Archives: Projects

Old radio clock upgraded to NTP

I own the radio clock on the title picture. I’ve used it for some time but it annoyed me because it drifted a lot (several seconds a day). It’s synchronized to power network frequency but it doesn’t work well in my case and I hate to adjust the clock over and over again. So I decided to sync it automatically using esp8266. Continue reading Old radio clock upgraded to NTP

$2 USB crypto token for use with GPG and SSH

If you are interrested in security devices this post may be for you. Recently I’ve found a software which makes a GPG security device out of a STM32. It’s called Gnuk. You just need a compatible board, programmer, flash the firmware and you are ready to go. I was just hoping to find some cheap device to flash to play with it.

Continue reading $2 USB crypto token for use with GPG and SSH

New version of Lenkeng HDMI over IP extender – LKV373A (Update 20. oct 2017)

Last week I’ve got the new version of Lenkeng HDMI extender – LKV373A. This version states incompatibility with previous version and usage of new HDbitT protocol so I was wondering what did Chinese engineers invent this time.

This blog is a log of my findings as they went through time. If you want a short review of the device watch this video from OpenTechLab (thank you!):

If you want to know more, just read the blog. Continue reading New version of Lenkeng HDMI over IP extender – LKV373A (Update 20. oct 2017)

Multicast over “stupid” networks

IP multicast is an interesting technology. It’s main purpose is to
save network bandwidth as much as possible – traffic is sent to hosts
which asked for it only (as opposed to broadcast). On the other
side, you need smarter (manageable) switches and separate and
non-trivial configuration on both routers and switches. Even more
complicated it is when you try to make it work over VPN. Continue reading Multicast over “stupid” networks

Yet another IoT thermostat

Hi all,

this post will be about my homemade IoT thermostat.  The goal was to not install any cables (because I live in a rented flat), to go really cheap and to be able to set the temperature from anywhere. I’ll also give you some tips you should think about when building your own. Let’s get started.

Continue reading Yet another IoT thermostat