Fifty years ago, several mathematicians at a dinner party were discussing graphs (points and lines, not chart graphs), and the generalization if you make the edges connecting a point (vertex) with another, able to connect multiple points. While working out the minimal number of colors in general, they found it to be an interesting problem, to test out and prove the next day… Well, that solution, to Erdős, Faber, and Lovász’ problem was delayed for years and years!
Continue reading “Mathematicians submit proof of Erdős Coloring Conjecture”App development with Librem 5
Purism’s blog recently posted a new howto on building a Librem 5 app. If you have been wanting to build a Linux app this is a great time to start with both phones and desktops running your app.
Continue reading “App development with Librem 5”Severe weather alerts with a simple Python script
If like many you have been starting gardens and planting rather than traveling and visiting in recent months, there is one important thing to consider lately – severe weather reports including frost on your crops. I noted there was a little red (!) alert icon on an Android weather widget, but there seems to be no such alert for desktop computer or Linux computer or phone. It is a fairly simple to make this alert though with a simple script:
Continue reading “Severe weather alerts with a simple Python script”Introducing the new EMP-proof Ham Radio Repeater Listing
If you have been using Amateur radio for some time you may know about the app connected to hearham.live repeater listing, which lets you keep an offline record of radio repeaters and a topo-map, on your Linux computer, tablet, phone, or even Android phone. But what would you do during an EMP or solar event causing extended downtime and damage of all computer devices?
Continue reading “Introducing the new EMP-proof Ham Radio Repeater Listing”5 reasons to order the new Swytch kit ebike kit
Swytch is a relatively new company building small and lightweight electric bicycle kits. Like most other electric bicycles, it offers a bit of a boost while pedaling, with hardly any noise or extra complexity of messy liquid fuels. So why might you want an assist from a Swytch kit installation..?
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Happy Pi day! Hope you are enjoying making pie (within your household/pod) and learning some new math stuff today! Matt Parker has an interesting video up on an attempting to calculate pi from a diameter of one-molecule thick droplet spreading on water:
Continue reading “Happy Pi day 2021!”Listening for a callsign on DMR with Hearham.live
These past few weeks have certainly been trying for some communities with power outages, winter weather and utility failures. Ham radio is a very good way to communicate in your local community, but what if lots of other people are on the local repeater? What if you want a notification if your child or buddy is calling you, but not every other kerchunk or distracting story on the local repeater? If you have a DMR digital radio and id and digital repeater nearby, the tools on Hearham.live may help – and help save your battery leaving a radio on all day 🙂
Continue reading “Listening for a callsign on DMR with Hearham.live”Review: Radioddity GD77 DMR Radio
The Radioddity is a fairly popular affordable amateur radio, and a good entry level way to get into DMR radio. (You may use this referral code for a discount)
Continue reading “Review: Radioddity GD77 DMR Radio”Upgrading PHP Nginx on Ubuntu 18.04
If you have ever installed WordPress on Ubuntu 18.04 or similar you may have noticed the WordPress warning in site health dashboard for the included default of old PHP 7.2. – “PHP is the programming language used to build and maintain WordPress. Newer versions of PHP are created with increased performance in mind, so you may see a positive effect on your site’s performance. The minimum recommended version of PHP is 7.4.” Furthermore if you do any experimenting with Laravel you may have issues because the latest Laravel 8 is only compatible with PHP7.3 and newer, among other changes.
Continue reading “Upgrading PHP Nginx on Ubuntu 18.04”Mars rover has landed
If you haven’t heard the news or live stream, today the Perseverance rover landed, with the first extraterrestrial helicopter!
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