We started producing shows as Today with a Techie on 2005-09-19, 16 years, 4 months, 5 days ago. Our shows are produced by listeners like you and can be on any topic that "are of interest to hobbyists". If you listen to HPR then please consider contributing one show a year. If you record your show now it could be released in 15 days.
Please help out tagging older shows !
Toshiba Satellite L455-S5000
https://www.ifixit.com/Device/Toshiba_Satellite_L455-S5975
The script!
#!/bin/bash
# target dir is ~/Photos/YYYY-MM-DD_Hm
targetDir="/home/$USER/Photos/$(date +"%F_%H%M")"
# create the dir
mkdir $targetDir
# cd to dir
cd $targetDir
# kill all gphoto stuff
pkill -f gphoto2
# get the files
gphoto2 --get-all-files
# delete all files on camera recursively
gphoto2 -DRI used to use Vagrant to spin up minimal virtual machines when I needed to test code on a different distro than what I ran. Lately I've switched to Podman.
Install Podman with your distribution's package manager.
Configure it:
$ sudo --add-subuids 200000-265536 \
--add-subgids 200000-265536 \
$USER
Create a directory to share data between your container and your localhost:
$ mkdir data
Run a container, with your ./data directory mapped to /storage in the container:
$ podman run -it --volume ./data:/storage:Z busybox
Hosted by Ahuka on 2022-01-14 is flagged as Clean and released under a CC-BY-SA license.
Tags: DOS, early PC computing, syntax, switches, help.
Listen in ogg, spx, or mp3 format.
Series: DOS | Comments (1)
Since DOS is a command line type of operating system, it is really important that you understand the syntax of commands. The good news is that the system will do what you tell it to do. But the bad news is that it will do what you tell it to do. You have to tell it in the precisely correct way, and that means Syntax. And with a number of commands you can modify them using Switches. And where do you learn all about Syntax and Switches? Why, in the HELP system, of course!
In this episode, the Inlaws are hosting Neil Johnson, VP of Engineering at Element. But this is not just about this popular Matrix graphical user interface but rather about this federated communication network dubbed as the next big thing after Mastodon and Discord, soon to take over the world (pretty much like the Inlaws themselves - it's gonna get crowded... :-).
Hosted by tuturto on 2022-01-12 is flagged as Clean and released under a CC-BY-SA license.
Tags: haskell, c#, programming.
Listen in ogg, spx, or mp3 format.
Series: Haskell | Comments (0)
This episode covers some of the differences between C# and Haskell. I'm probably going to omit lot of things accidentally.
Thanks for listening, if you have any questions or comments, you can reach me via email or in fediverse, where I'm tuturto@tech.lgbt. Or even better, you could record your own hacker public radio episode.
Hosted by Archer72 on 2022-01-11 is flagged as Clean and released under a CC-BY-SA license.
Tags: Vinyl, album, Vinyl album, record album, aplay, arecord, alsaloop, ffmpeg,retro, USB turntable.
Listen in ogg, spx, or mp3 format.
Comments (0)
Partial list of albums
Inside Star Trek album: Cover
Click the
thumbnail to see the full-sized image - -
Inside Star Trek album: Contents
Click the thumbnail to see the full-sized image - -
I found a turntable at the thrift store, and the spindle ran, but the platter did not. The belt had slipped off, and here is the fix.
How to remove platter
Click the thumbnail to see the full-sized image - -
Belt placement
Click the thumbnail to see the full-sized image - -
Send input to output
alsaloop -t 500000 -C hw:CARD=CODEC,DEV=0 -P default:CARD=b1https://linux.die.net/man/1/alsaloop
-t
Parameter b1 is found by
pi@retropie:~ $ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: b1 [bcm2835 HDMI 1], device 0: bcm2835 HDMI 1 [bcm2835 HDMI 1]https://scruss.com/blog/2012/11/20/raspberry-pi-as-a-usb-audio-capture-device
arecord -D 'pulse' -V stereo -c 2 -f dat -d 900 out.wav
arecord -D 'hw:CARD=CODEC,DEV=0' -V stereo -c 2 -f dat -d 900 out.wav
Used hw:CARD=CODEC,DEV=0 derived from 'arecord -L'
hw:CARD=CODEC,DEV=0
USB Audio CODEC, USB Audio
Direct hardware device without any conversions -D, --device=NAME
Select PCM by name
-V, --vumeter=TYPE
Specifies the VU-meter type, either stereo or mono. The stereo VU-meter is available only for 2-channel stereo samples with interleaved format.
-c, --channels=#
The number of channels. The default is one channel. Valid values are 1 through 32.
-f --format=FORMAT
Sample format
Recognized sample formats are: S8 U8 S16_LE S16_BE U16_LE U16_BE S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE FLOAT_BE FLOAT64_LE FLOAT64_BE IEC958_SUBFRAME_LE IEC958_SUBFRAME_BE MU_LAW A_LAW IMA_ADPCM MPEG GSM SPECIAL S24_3LE S24_3BE U24_3LE U24_3BE S20_3LE S20_3BE U20_3LE U20_3BE S18_3LE S18_3BE U18_3LE
Some of these may not be available on selected hardware
The available format shortcuts are:
-f cd (16 bit little endian, 44100, stereo) [-f S16_LE -c2 -r44100]
-f cdr (16 bit big endian, 44100, stereo) [-f S16_BE -c2 -f44100]
-f dat (16 bit little endian, 48000, stereo) [-f S16_LE -c2 -r48000]How can one record mic audio straight to a FLAC file?
ffmpeg -f alsa -ar 48000 -ac 1 -i hw:0 testfile.flacChange hw:0 to hw:2 based on
pi@retropie:~/vinyl $ arecord -l
**** List of CAPTURE Hardware Devices ****
card 2: USB20 [AV TO USB2.0], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
ffmpeg -f alsa -ar 48000 -i hw:2 testfile_stereo.flachttps://hackerpublicradio.org/calendar.php
Hosted by beni on 2022-01-07 is flagged as Clean and released under a CC-BY-SA license.
Tags: Swiss,BAKOM,HamRadioTrainer,HB9.
Listen in ogg, spx, or mp3 format.
Series: HAM radio | Comments (1)
The HAM Page of the Swiss Federal Office of Communications, BAKOM: https://www.bakom.admin.ch/bakom/de/home/frequenzen-antennen/frequenznutzung-mit-oder-ohne-konzessionen/amateurfunk.html
Union of Swiss Short Wave Amateurs, they manage the local associations and the use of the frequencies for relays and automated stations: https://www.uska.ch/en/
Most likely the best way to prepare for the exam is attending a preparation course from a local Association, of have a brother who did and forwarded all the background info and documents to me. ;) But apart from having a brother I did the following:
The online version of the books I read: https://www.darc.de/der-club/referate/ajw/darc-online-lehrgang/ - again in German. They're mainly geared towards the German exams but the knowledge contained is useful for the Swiss exams, too.
I mainly used the HamRadioTrainer to prepare for the exam. This is a Windows application which however works pretty well in wine. I was told that the Swiss questions are rather old, 2017ish.
I was told that there are mobile apps with more recent questions but I couldn't be bothered to check whether they exist on F-Droid.
The BAKOM also has a site about the exams, containing PDFs with example questions, of course again everything in German: https://www.bakom.admin.ch/bakom/de/home/frequenzen-antennen/funkerpruefungen/amateurfunk-pruefungen.html
Hosted by Dave Morriss on 2022-01-06 is flagged as Explicit and released under a CC-BY-SA license.
Tags: astronomy,telescope,rocket launch,JWST,NASA,ESA,CSA.
Listen in ogg, spx, or mp3 format.
Comments (1)
On Christmas Day 2021 at 12:20 UTC the James Webb Space Telescope was launched. This is the largest telescope ever sent into space and the project has been delayed for many years. The entire astronomical community was very nervous about the launch and about the phase that will follow as the telescope is set up for use.
Andrew Conway was previously a professional Astronomer, and Dave is very interested in the subject as an amateur. They got together on Mumble to witness the launch, and the dialogue was recorded and is presented here.
Quote from Wikipedia (a page that is being updated as the project proceeds):
The James Webb Space Telescope (JWST) is a space telescope developed by NASA with contributions from the European Space Agency (ESA), and the Canadian Space Agency (CSA). The telescope is named after James E. Webb, who was the administrator of NASA from 1961 to 1968 and played an integral role in the Apollo program. It is intended to succeed the Hubble Space Telescope as NASA’s flagship mission in astrophysics. JWST was launched 25 December 2021 on Ariane flight VA256. It is designed to provide improved infrared resolution and sensitivity over Hubble, and will enable a broad range of investigations across the fields of astronomy and cosmology, including observations of some of the most distant events and objects in the Universe such as the formation of the first galaxies, and allowing detailed atmospheric characterization of potentially habitable exoplanets.
JWST’s primary mirror, the Optical Telescope Element, consists of 18 hexagonal mirror segments made of gold-plated beryllium which combine to create a 6.5 meter (21 ft 4 inch) diameter mirror – considerably larger than Hubble’s 2.4 m (7.9 ft) mirror. Unlike Hubble, which observes in the near ultraviolet, visible, and near infrared (0.1–1.0 μm) spectra, JWST will observe in a lower frequency range, from long-wavelength visible light (red) through mid-infrared (0.6–28.3 μm). This will enable it to observe high-redshift objects that are too old and too distant for Hubble. The telescope must be kept very cold to observe in the infrared without interference, so it will be deployed in space near the Sun–Earth L2 Lagrange point, about 1.5 million kilometers (930,000 mi) from Earth. A large sunshield made of silicon- and aluminum-coated Kapton will keep its mirror and instruments below 50 K (−223 °C; −370 °F).
The NASA Goddard Space Flight Center (GSFC) in Maryland managed the development and the Space Telescope Science Institute is operating JWST. The prime contractor was Northrop Grumman.
Development began in 1996 for a launch that was initially planned for 2007 with a US$500 million budget. There were many delays and cost overruns, including a major redesign in 2005, a ripped sunshield during a practice deployment, a recommendation from an independent review board, the COVID-19 pandemic, issues with the Ariane 5 rocket and the telescope itself, and communications issues between the telescope and the launch vehicle. Concerns among the involved scientists and engineers about the launch and deployment of the telescope have been well-described.
Construction was completed in late 2016, when an extensive testing phase began. JWST was launched 12:20 UTC 25 December 2021 by an Ariane 5 launch vehicle from Kourou, French Guiana and was released from the upper stage 27 minutes later. The telescope was confirmed to be receiving power, and as of December 2021 is traveling to its target destination.
Andrew and Dave came up with the idea of watching the launch and talking about it on Mumble. Although this was not originally planned, the audio was recorded, and is included here.
Note: Dave’s audio had a background hum which has been reduced a little with Audacity’s notch filter. Hopefully it’s not too distracting.
We were puzzled that the altitude of the final stage of the rocket plus telescope decreased during launch. See the link below to a YouTube episode from Anton Petrov explaining what was going on.
In the context of orbital mechanics, Dave spoke of another mission which is heading to Mercury but passing by inner planets to adjust speed. The name couldn’t be recalled at the time, but it was BepiColombo which is taking a 7-year path to its destination.
At the time of preparing these notes (2022-01-02) the JWST is en route to the (Sun-Earth) L2 point, about 1 million miles (1.5 million kilometres) from Earth. Along the way it is preparing itself for use, deploying the features which were folded up or stowed away when it was being launched. See the deployment explorer site for details of what is happening.
There are enormous amounts of information about this project on the web, some examples of which are linked below. Searching with your favourite search engine will certainly reveal more.
Hosted by Ken Fallon on 2022-01-05 is flagged as Clean and released under a CC-BY-SA license.
Tags: mumble,hpr mumble, new year show.
Listen in ogg, spx, or mp3 format.
Comments (0)
The complete shownotes are available in our mumble how-to.
When using Mumble you should always use a microphone and headset positioned close to your mouth but slightly off to the side.
The Mumble website offers download and install instructions for different operating systems.
Once you have installed the client then connect to the HPR Room on Mumble.
There is a first run wizard that will step you through the process of configuring Mumble the first time. This will open up a series of configuration options.
It is very important that you set Push to Talk (PTT) and you Disable Text-To-Speech, as you will disturb the other people in the room if you select the other methods. It may seem to be working fine to you, but it will result in issues for the others.
You are expected to have a digital certificate when connecting to Mumble servers. An automatically created one is usually fine.
Once you have the Mumble client set up we can now start the process of connecting to the HPR Room on Mumble.
If at any time you need to add the HPR server open mumble and press Server - Connect, press Add New...and enter the following information for the HPR server:
Think about your username a bit as if you register it on the server you will not be able to change it again.
Before connecting to any room it's good etiquette to make sure your audio is working correctly. The room Audio Test will allow you to speak and the OpieTheRepeatherBot will record your speech and after 10 seconds will play it back for you.
Get a full list of all our shows.