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I’m a weather nerd. I like all things weather related. Around 10 years ago I ran across an interesting project to track lightning strikes around the world. Blitzortung.

Blitzortung is a community-based lighting detection network that uses Time of Arrival (TOA) and Time of Group Arrival methods to locate lightning strikes. It relies on a network of distributed, low-cost receiver stations, run and assembled by volunteers, to detect VLF radio waves emitted by lightning. By measuring the time it takes for these signals to arrive at different stations, the system can triangulate the strikes location.

I won’t go into great detail here on how it works, as you can find that information on the Blitzortung project pages. What I will show here is a little about my receiving station.

My station is a “System Red” PCB 10.4 detector. I purchased it as a kit and assembled it. I had to build my own antennas. You can find out a ton more information about the receiver and how it all works at the System Red link.

I chose to use Ferrite Rod antennas for my application. I wound the antenna on ferrite rods, shoved them inside a piece of 1/2″ PEX tubing, then wrapped them in copper tape with a 2mm slit to provide shielding. That all get put into a 3/4″ PVC pipe to weather proof the elements. There are two of these antennas, one is mounted vertically and one horizontally.

Antenna after insertion in PEX tubing and wrapping it with the copper shielding tape.

The completed antenna and the outdoor amplifier board.

I attached the completed antenna to my privacy fence in the backyard. Shielded CAT5 Ethernet cable connects the amplifier to the main controller. I also mounted the necessary GPS antenna outdoors.

Inside is the Main Controller, mounted to a wall in my basement.

It all works surprisingly well, though it does suffer from some interference. The spot on the fence seems to be one of the quieter spots. Mounting it on the side of the house was a lot worse interference wise.

This isn’t a simple build it and it will work setup. You have to be willing to tweak antennas and locations to find the “best” spot for the antennas.

System Red is long since discontinued, but is still supported by the network, and was replaced by System Blue, but I believe these are sold out.

Blitzortung is run completely by hobbyists, so their resources are a bit limited. In addition to making and selling the kits they also have to operate the servers that aggregate the data and calculate the lightning locations. They make the data freely available at www.lightningmaps.org. If you use their data please consider a donation to keep things running.

I had been wanting a nice digital UTC clock for my hamshack. In particular one that could set itself to an NTP server over the internet to maintain precise time. But I was having trouble finding a WiFi NTP clock at a price I was willing to pay. Most of the ones I was finding online were $200 or more. So what’s a ham to do? Build your own!

After a lot of searching for what I wanted, I ran across this project (see notes at end of post) over at Adafruit, and seemed like it just might fit the bill. And it did.

I used a Raspberry Pi Zero W as the brains, and the Adafruit 1.2″ 4-Digit 7-Segment Display w/I2C Backpack for the display. I followed the rest of the tutorial and it worked great.

After trying it for some time I was happy with it, and found a Polycase enclosure that was almost the right size. At least for the 7-segment display itself. With it soldered to the backpack it was way too tall. So why not run it remotely from the backpack board? Using some jumper wires I did just that, and with only some minor Dremeling to the enclosure to make it fit perfectly.

I used some red plexiglass on the front and it looks great in the shack. And it’s a bonus that the time is always correct. Just be sure that when you configure the Pi you set it to use UTC time.

Finished WiFi NTP Clock — The finished LED Wifi NTP Clock

All together I spent around $60 to build this clock.

NOTES:
Before pip3 command can be run, you need to do this:
sudo apt-get install python3-pip
You also need to run the pip3 commands as sudo.

It appears the github content for this project has gone 404, so you may have to create the python code files yourself.

You also will have to set the program to run as a service and should consider ways to extend the life of the SD card by reducing writes.