This show has been flagged as Explicit by the host.
Introduction
MrXDaveMorriss
We recorded this on Saturday September 14th 2024. This
time we were at Swanston Farm, a place we had previously visited for
After lunch we adjourned to Dave's car (Studio N) in the car
park, and recorded a chat. The details of why it is Studio N
instead of Studio C is mentioned in the chat itself!
Preparing this show has taken longer than usual this time
Topics discussed
Studio change:Sadly, since the last recording Studio C (Dave's 10-yearold Citroën C4
Picasso) self-destructed. It was a diesel car and one of the fuel
injectors failed and destroyed the engine management system as it died.
It wasn't worth repairing!
The replacement is Studio N, a Nissan Leaf, which is an EV (electricvehicle). The price of nearly new EV cars is fairly good in the UK
at this time in 2024, so it seemed like a good opportunity to get
one.
Learning to own and drive an EV can be challenging to some extent:"Range anxiety" and access to charging stationsRegenerativebraking
Fast (DC) charging on the road is relatively expensive (£0.79p perkWh), but is convenient
Ideally, a home (AC) charger is required. It will be slower (7 kWper hour) but will be cheaper with a night tariff (£0.085 per kWh versus
£0.25 per kWh normal rate)
There is potential, with solar panels and a battery, to use freeelectricity to charge an EV at home
MrX might like to move to an EV in the futureYouTube channels:Dave is subscribed to a channel called "The PostApocalyptic Inventor (TPAI)" and recently shared one of the
latest videos with MrX. The channel owner collects
discarded items from scrapyards in Germany, or buys old bits of
equipment, and gets them working again.
MillingMachine Adventure! Bring her Home! / Gantry Build
I built a CNCPlasma Cutting Table from Scrap!
Databases:MrX used dBase on DOS in the past,and received some training in databases.
In 2017 he obtained a large csv(comma-separated values) file from the OFCOM (Office of
Communications, UK) website containing their Wireless Legacy
Register, which contains licensees and frequencies with longitude
and latitude values. A means of interrogating this file was sought,
having found that spreadsheets were not really very good at handling
files of this size (around 200,000 records).
MrX used the xsv tool, which was coveredin shows hpr2698
and hpr2752
by Mr.
Young. It allows a CSV file to be interrogated in quite a lot of
detail from the command line. However, with a file of this size it was
still quite slow.
In a discussion with Dave the subject of the SQLite database came up.Using the SQLite Browser it was
simple to load this CSV file into a database and gain rapid access to
its contents. SQLite databases may also be queried through a
command-line interface which can also be run on a Raspberry Pi, phones,
tablets and on a ChromeBook.
The textimgtool:
This is a command to convert from colored text (ANSI or 256) to animage. Dave generates coloured text from his meal database (HPR show hpr3386 ::
What's for dinner?, this being a later enhancement), then captures
the output and sends it to a Telegram channel shared with his
family.
Dave also exchanges weather data obtained from the sitewttr.in with Archer72
on Matrix.
This is a useful tool for generating images from text, including anytext colours. It can be installed from the GitHub copy, and maybe from
some package repositories.
Using coloured text in BASH (Dave responding to MrX):I have used a function to define variables with colour names:Call a function define_colours which defines (andexports) variables called red, green,
etc.
Using red=$(tput setaf 1); export redI use the colours in two ways:Method 1: use these names inecho "${red}Red text${reset}"
Method 2: use another function coloured which takes twoarguments, a colour name (as a string) and a message. The script
encloses the message argument in a colour variable and a reset. The
colour name argument is used in a redirection to turn red
into the contents of the variable $red.
This probably needs a show to explain things fully.Terminal multiplexers:Dave and MrX use GNU screen.Both recognise that the alternative tmux might bebetter to use in terms of features, but are reluctant to learn a new
interface!
Dave has noticed a new open-source alternative called zellij but has not yet used it.Variable weather:Dealing with hot weather: YouTube, Techmoan channel PERSONAL AIRCON -Ranvoo Aice Lite Review
MrX had recently had a holiday in the Lake Districtwhere the weather was good.
In Scotland the weather has been wet and windy in the sameperiod.
Spectrum24, OggCamp:MrX is attending his first OggCamp in Manchester. Dave will beattending too, as will Ken.
HPR has a table/booth at OggCamp.Ken was recently at Spectrum24, an amateur radioconference in Paris.
Meshtastic an open source,off-grid, decentralized, mesh network built to run on affordable,
low-power devices
Old inkjet printers:MrX has an Epson R300 printer where the black ink seemsto have dried up.
Dave has an old HP Inkjet with the same type of problem. Thisprinter has a scanner and FAX capability. An HPR show
was done in 2015 describing how it was set up to use a Raspberry Pi to
make it available on the local network.
Propelling or mechanical pencils:Dave had a Pentel GraphGear 1000 propelling (aka mechanical) pencilwhich was mentioned on HPR show
3197. This was dropped onto concrete, and didn't appear damaged at
the time, but it apparently received internal damage and eventually fell
apart.
Links
Electric cars:EV(electric vehicle)
Regenerativebraking
DatabasesSQLite:SQLiteSQLite BrowserAn Easy Way to MasterSQLite Fast
Open source SQLite Studio available for Linux SQLiteStudioSQL:Origins: TheBirth of SQL & the Relational Database
Intricacies: MySQLJOIN Types Poster (Steve Stedman)
Design:Howto Fake a Database Design - Curtis Poe (Ovid)
The textimg tool:GitHub repository: textimgzellij:Website: zellijGithub repository: zellijQuote from the repo: Zellij is a workspace aimed at developers,ops-oriented people and anyone who loves the terminal. Similar programs
are sometimes called "Terminal Multiplexers".
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