# articles

feed_id: http://www.dotmana.com/weblog/?p=2218
title: Linux/Ubuntu: Speaking clock with online TTS
uri: Linux-Ubuntu-Speaking-clock-with-online-TTS
url: http://www.dotmana.com/weblog/2017/01/linuxubuntu-speaking-clock-with-online-tts/
content:
<p>As a followup of my previous article:</p>
<blockquote data-secret="SlYWdAHMgz" class="wp-embedded-content"><p><a href="http://www.dotmana.com/weblog/2013/02/ubuntu-talking-clock-every-hours/">Ubuntu: talking clock every hours</a></p></blockquote>
<p><iframe class="wp-embedded-content" sandbox="allow-scripts" security="restricted" src="http://www.dotmana.com/weblog/2013/02/ubuntu-talking-clock-every-hours/embed/#?secret=SlYWdAHMgz" data-secret="SlYWdAHMgz" width="584" height="329" title="&#8220;Ubuntu: talking clock every hours&#8221; &#8212; DotMana" frameborder="0" marginwidth="0" marginheight="0" scrolling="no"></iframe></p>
<p>4 years after the previous article, I still need this tool, but I wanted a more &#8220;natural&#8221; TTS.</p>
<p>So I&#8217;m using <a href="https://www.voxygen.fr/">Voxygen</a>, a natural TTS provider (very good for French), retrieving the generated voice with wget and the following command:</p>
<pre>wget --quiet --no-check-certificate -O /tmp/clock_`date +\%-1H`.mp3 "https://www.voxygen.fr/sites/all/modules/voxygen_voices/assets/proxy/index.php?method=redirect&amp;text=il est exactement `date +\%-1H` heures.&amp;voice=Loic"</pre>
<p>Here is the script to run every hours:</p>
<pre>if [ ! -e /tmp/clock_`date +\%-1H`.mp3 ]; then wget --quiet --no-check-certificate -O /tmp/clock_`date +\%-1H`.mp3 "https://www.voxygen.fr/sites/all/modules/voxygen_voices/assets/proxy/index.php?method=redirect&amp;text=il est exactement `date +\%-1H` heures.&amp;voice=Loic"; fi ; mpg321 /tmp/clock_`date +\%-1H`.mp3 --gain 200</pre>
<p>We will be using gnome schedule taks:</p>
<p><a href="http://www.dotmana.com/weblog/2017/01/linuxubuntu-speaking-clock-with-online-tts/screenshot-from-2017-01-05-100935/" rel="attachment wp-att-2222"><img class="aligncenter size-full wp-image-2222" src="media/3835a838.Screenshot-from-2017-01-05-100935.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-01-05-100935.png" alt="screenshot-from-2017-01-05-100935" width="905" height="545" srcset="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-01-05-100935.png 905w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-01-05-100935-300x181.png 300w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-01-05-100935-768x462.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-01-05-100935-498x300.png 498w" sizes="(max-width: 905px) 100vw, 905px" /></a></p>


feed_id: http://www.dotmana.com/weblog/?p=2235
title: Plastic part surface finish: please stop making mirror products
uri: Plastic-part-surface-finish-please-stop-making-mirror-products
url:
http://www.dotmana.com/weblog/2017/04/plastic-part-surface-finish-please-stop-making-mirror-products/

content:
<p>They are simply dust, fingerprint and scratch magnet, everything is summarised in the amazing book <strong><span id="productTitle" class="a-size-extra-large">The Hardware Hacker: Adventures in Making and Breaking Hardware </span></strong>from <a href="https://www.bunniestudios.com/">Andrew &#8216;bunnie&#8217; Huang</a></p>
<p><img class="aligncenter size-full wp-image-2236" src="media/2685650a.514FY5Hw55L._SY291_BO1204203200_QL40_.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/514FY5Hw55L._SY291_BO1204203200_QL40_.jpg" alt="" width="195" height="293" /></p>
<blockquote><p>&#8220;My world is full of small frustrations like this. For example, most customers perceive plastics with a mirror finish to be of a higher quality than those with a satin finish. There is no functional difference between the two plastics&#8217; structural performance, but making something with a mirror finish takes a lot more effort. The injection-molding tools must be pains-takingly and meticulously polished, and at every step in the factory, workers must wear white gloves. Mountains of plastic are scrapped for hairline defects, and extra films of plastic are placed over mirror surfaces to protect them during shipping. For all that effort, for all that waste, what&#8217;s the first thing users do? They put their dirty fingerprints all over the mirror finish. Within a minute of a product coming out of the box, all that effort is undone. Or worse yet, the user leaves the protective film on, resulting in a net worse cosmetic effect than a satin finish. Contrast this to satin-finished plastic. Satin finishes don&#8217;t require protective films, are easier for workers and users to handle, last longer, and have much better yields. In the user&#8217;s hands, they hide small scratches, fingerprints, and bits of dust. Arguably, the satin finish offers a better long-term customer experience than the mirror finish. But that mirror finish sure does look pretty in photographs and showroom displays!&#8221;</p></blockquote>


feed_id: http://www.dotmana.com/weblog/?p=2239
title: Linux: hide cursor when typing
uri: Linux-hide-cursor-when-typing
url: http://www.dotmana.com/weblog/2017/05/linux-hide-mouse-when-typing-on-keboard/
content:
<p>Very basic feature, yet not present in Linux.</p>
<p>This very simple tool, <a href="https://github.com/jcs/xbanish">xbanish</a>, hide mouse&#8217;s cursor away when you start typing, and is restored back when moving the mouse.</p>


feed_id: http://www.dotmana.com/weblog/?p=2232
title: Renault Trafic II (2001): pdf manuel atelier
uri: Renault-Trafic-II-(2001)-pdf-manuel-atelier
url: http://www.dotmana.com/weblog/2017/05/renault-trafic-ii-2001-pdf-manuel-atelier/
content:
<p><img class="aligncenter size-large wp-image-2245" src="media/70c9b1b7.Screenshot-from-2017-05-11-085941-707x1024.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-05-11-085941-707x1024.png" alt="" width="584" height="846" srcset="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-05-11-085941-707x1024.png 707w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-05-11-085941-207x300.png 207w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-05-11-085941-768x1112.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-05-11-085941.png 773w" sizes="(max-width: 584px) 100vw, 584px" /></p>
<p><a href="media/a2bed99b.revue-technique-renault-trafic-II.pdf" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/revue-technique-renault-trafic-II.pdf">Renault Trafic II (2001): pdf manuel atelier.pdf</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2249
title: Aménagement des camping-cars – Confort et sécurité des occupants – AFNOR ISBN 978-2-12-415661-0
uri: Aménagement-des-camping-cars-Confort-et-sécurité-des-occupants
url:
http://www.dotmana.com/weblog/2017/07/amenagement-des-camping-cars-confort-et-securite-des-occupants-afnor-isbn-978-2-12-415661-0/

content:
<p><img class="aligncenter size-medium wp-image-2250" src="media/4c21ad2e.Screenshot-from-2017-07-09-171139-202x300.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-07-09-171139-202x300.png" alt="" width="202" height="300" srcset="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-07-09-171139-202x300.png 202w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-07-09-171139-768x1138.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-07-09-171139-691x1024.png 691w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2017-07-09-171139.png 797w" sizes="(max-width: 202px) 100vw, 202px" />Télécharger le PDF <a href="http://www41.zippyshare.com/v/VxzBLM9U/file.html">ici</a> ou mirror <a href="https://mega.nz/fm/ciZmRIiQ">ici</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2252
title: Webradio
uri: Webradio
url: http://www.dotmana.com/weblog/2017/07/webradio/
content:
<p>Download a RPI image, in this case, I choose : <a href="http://pipaos.mitako.eu/">pipaOS A lighweight, fast, Raspbian based distro for the Raspberry PI</a></p>
<p>Once the image unziped, copy to a fresh high performance micro SD card</p>
<pre>sudo dd bs=4M if=./pipaos-tamarillo-4.7.img of=/dev/mmcblk0</pre>
<p>in order to boost performances, I use a Samsung EVO+ for high performance for a very fast boot</p>
<p>&nbsp;</p>
<pre>ssh sysop@192.168.1.84 (password posys)</pre>
<h1>Connect to WIFI network</h1>
<p>Rpi 3 rev B and Zero W have integrated wifi</p>
<h2>Edit WIFI credentials</h2>
<p>The file  /etc/network/interfaces should NOT be modified, as it&#8217;s overwritten at start.</p>
<p>Edit the file</p>
<pre>sudo nano /boot/network.ini</pre>
<p>To add your credential:</p>
<pre>#
 # interfaces - setup your networking devices here
 #

auto lo
 iface lo inet loopback

allow-hotplug eth0
 iface eth0 inet dhcp

allow-hotplug usb0
 iface usb0 inet dhcp

# pipaOS Will automatically try to connect
 # to wireless ESSID "pipaos" passphrase "pipa123pass"
 allow-hotplug wlan0
 iface wlan0 inet dhcp
 wpa-ssid YOUR_SSSID
 wpa-psk YOUR_WIFI_KEY</pre>
<h1>High quality sound</h1>
<p>Rasberry Pi have 3.5mm stereo jack output but the quality is pure crap, wondering why they even bother populate a jack.</p>
<p>So lets connect a cheap UBS sound card and check what appends</p>
<pre>dmesg</pre>
<p>sould display something like</p>
<pre>[ 106.865142] usb 1-1.2: new full-speed USB device number 5 using dwc_otg
 [ 107.006372] usb 1-1.2: New USB device found, idVendor=0d8c, idProduct=0102
 [ 107.006387] usb 1-1.2: New USB device strings: Mfr=0, Product=2, SerialNumber=0
 [ 107.006395] usb 1-1.2: Product: USB Sound Device

[ 107.042816] input: USB Sound Device as /devices/platform/soc/3f980000.usb/usb1/1-1/1-1.2/1-1.2:1.3/0003:0D8C:0102.0002/input/input1
 [ 107.105630] hid-generic 0003:0D8C:0102.0002: input,hidraw0: USB HID v1.00 Device [USB Sound Device ] on usb-3f980000.usb-1.2/input3</pre>
<p>and</p>
<pre>lsusb</pre>
<p>will output:</p>
<pre> Bus 002 Device 009: ID 0d8c:0102 C-Media Electronics, Inc. CM106 Like Sound Device
 Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub</pre>
<p>&nbsp;</p>
<h1>Create startup service : webradio</h1>
<pre>sudo apt-get install mplayer</pre>
<pre>mplayer `curl -w "%{url_effective}\n" -I -L -s -S http://direct.fipradio.fr/live/fip-midfi.mp3 -o /dev/null`</pre>
<h2>Webradio player script</h2>
<p>create non returning script:</p>
<pre>sudo nano /home/sysop/webradio.sh</pre>
<pre>while true
 do mplayer http://chai5she.cdn.dvmr.fr:80/fip-midfi.mp3
 sleep 1
 done</pre>
<h2>create init.d service: webradio</h2>
<pre>#!/bin/bash
 #webradio daemon
 # chkconfig: 345 20 80
 # description: mwebradioapp daemon
 # processname:webradio

DAEMON_PATH="/"

DAEMON=/home/sysop/webradio.sh
 DAEMONOPTS=""

NAME=myapp
 DESC="My daemon description"
 PIDFILE=/var/run/$NAME.pid
 SCRIPTNAME=/etc/init.d/$NAME

case "$1" in
 start)
 printf "%-50s" "Starting $NAME..."
 cd $DAEMON_PATH
 PID=`$DAEMON $DAEMONOPTS &gt; /dev/null 2&gt;&amp;1 &amp; echo $!`
 #echo "Saving PID" $PID " to " $PIDFILE
 if [ -z $PID ]; then
 printf "%s\n" "Fail"
 else
 echo $PID &gt; $PIDFILE
 printf "%s\n" "Ok"
 fi
 ;;
 status)
 printf "%-50s" "Checking $NAME..."
 if [ -f $PIDFILE ]; then
 PID=`cat $PIDFILE`
 if [ -z "`ps axf | grep ${PID} | grep -v grep`" ]; then
 printf "%s\n" "Process dead but pidfile exists"
 else
 echo "Running"
 fi
 else
 printf "%s\n" "Service not running"
 fi</pre>
<h2>Install startup service</h2>
<pre>update-rc.d webradio defaults</pre>
<h2>Start service manually</h2>
<pre>sudo service webradio start</pre>
<h1>Check startup time and performance</h1>
<blockquote><p>Startup time with RPI 3 B: Startup finished in 2.602s (kernel) + 4.386s (userspace) = 6.988s</p></blockquote>
<p>Not bad at all for a full featured computer with wifi and usb audio</p>
<p><img class="aligncenter size-medium wp-image-2256" src="media/e0c899a6.rpi_pipos_startup-155x300.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/rpi_pipos_startup-155x300.png" alt="" width="155" height="300" srcset="http://www.dotmana.com/weblog/wp-content/uploads/rpi_pipos_startup-155x300.png 155w, http://www.dotmana.com/weblog/wp-content/uploads/rpi_pipos_startup-768x1490.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/rpi_pipos_startup-528x1024.png 528w, http://www.dotmana.com/weblog/wp-content/uploads/rpi_pipos_startup.png 1130w" sizes="(max-width: 155px) 100vw, 155px" /></p>


feed_id: http://www.dotmana.com/weblog/?p=2268
title: BROTHER DCP 9020CDW reset toner cartridge via the printer’s menu
uri: BROTHER-DCP-9020CDW-reset-toner-cartridge-via-the-printer-s-menu
url:
http://www.dotmana.com/weblog/2017/10/brother-dcp-9020cdw-reset-toner-cartridge-via-the-printers-menu/

content:
<p>Symptoms: the printer doesn&#8217;t want to print and ask for a toner change, no override.</p>
<p>Easy reset toner counter: open the top cover, hold the * button for 5 sec (close to keypad, not back-lighted, you can barely see it).</p>
<p>A reset menu appears and voila! Fuck you Brother! My toner don&#8217;t need to be changed, my next printer wont be one of yours.</p>
<p>&nbsp;</p>
<p>Source: <a href="https://printerthinker.com/brother-dcp-9020cdw/">https://printerthinker.com/brother-dcp-9020cdw/</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2273
title: Adding the “send to” via email action to your Nemo/Ubuntu
uri: Adding-the-send-to-via-email-action-to-your-Nemo-Ubuntu
url: http://www.dotmana.com/weblog/2017/11/adding-the-send-to-via-email-action-to-your-nemoubuntu/
content:
<p>How to get a &#8220;right click, send by email&#8221; menu in Nemo file browser:</p>
<p>Create the file:</p>
<p><strong>.local/share/nemo/actions/thunderbird.nemo_action</strong></p>
<p>Just cut and paste this inside that file and you’re done <img src="media/180db26c.1f642.png" data-original-source="https://s.w.org/images/core/emoji/2.3/72x72/1f642.png" alt="🙂" class="wp-smiley" style="height: 1em; max-height: 1em;" /></p>
<pre class="code prettyprint">[Nemo Action]
Name=Send by Email
Comment=Send by Email the files
Exec=thunderbird -compose to=,"attachment='%U'"
Icon-Name=thunderbird
Selection=notnone
Extensions=nodirs;
Separator=,
EscapeSpaces=false</pre>
<p>&nbsp;</p>
<p><a href="http://www.badpenguin.org/nemo-action-send-to-email">Source: http://www.badpenguin.org/nemo-action-send-to-email</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2308
title: Daewoo Chevrolet Kalos workshop service manual PDF
uri: Daewoo-Chevrolet-Kalos-workshop-service-manual-PDF
url: http://www.dotmana.com/weblog/2018/03/daewoo-chevrolet-kalos-workshop-service-manual-pdf/
content:
<p><a href="media/fafb28d5.daewoo_chevrolet_kalos_service_workshop_manual.pdf" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/daewoo_chevrolet_kalos_service_workshop_manual.pdf">daewoo_chevrolet_kalos_service_workshop_manual</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2325
title: Mini portable power supply DIY
uri: Mini-portable-power-supply-DIY
url: http://www.dotmana.com/weblog/2018/08/mini-portable-power-supply-diy/
content:
<p>Here is a small DIY project, for a portable/bench-top power supply. We are not aiming for the best regulation, neither most power. But portability and bench-top estate optimisation.</p>
<p>This is based on the famous <a href="https://www.google.fr/search?q=DPS3005+power+supply">DPS3005 (about 25€)</a></p>
<p><a href="media/0dc5aa54.r-Supply-module-buck-Voltage-converter-color-LCD.jpg_640x640.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/RD-DPS3005-Constant-Voltage-current-Step-down-Programmable-Power-Supply-module-buck-Voltage-converter-color-LCD.jpg_640x640.jpg"><img class="aligncenter size-medium wp-image-2326" src="media/e2a415e7.-module-buck-Voltage-converter-color-LCD.jpg_640x640-300x262.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/RD-DPS3005-Constant-Voltage-current-Step-down-Programmable-Power-Supply-module-buck-Voltage-converter-color-LCD.jpg_640x640-300x262.jpg" alt="" width="300" height="262" srcset="http://www.dotmana.com/weblog/wp-content/uploads/RD-DPS3005-Constant-Voltage-current-Step-down-Programmable-Power-Supply-module-buck-Voltage-converter-color-LCD.jpg_640x640-300x262.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/RD-DPS3005-Constant-Voltage-current-Step-down-Programmable-Power-Supply-module-buck-Voltage-converter-color-LCD.jpg_640x640-344x300.jpg 344w, http://www.dotmana.com/weblog/wp-content/uploads/RD-DPS3005-Constant-Voltage-current-Step-down-Programmable-Power-Supply-module-buck-Voltage-converter-color-LCD.jpg_640x640.jpg 520w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>Let&#8217;s 3D print an enclosure, <a href="https://www.thingiverse.com/thing:2250644">found on Thingiverse:</a></p>
<p><a href="media/3750aa00.P80802-145548.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-145548.jpg"><img class="aligncenter size-medium wp-image-2327" src="media/18963e2d.P80802-145548-300x169.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-145548-300x169.jpg" alt="" width="300" height="169" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P80802-145548-300x169.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-145548-768x432.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-145548-1024x576.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-145548-500x281.jpg 500w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>And grab all the jelly beans needed:</p>
<p><a href="media/0b1471b2.P80802-150154.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-150154.jpg"><img class="aligncenter size-medium wp-image-2335" src="media/8678f697.P80802-150154-300x169.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-150154-300x169.jpg" alt="" width="300" height="169" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P80802-150154-300x169.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-150154-768x432.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-150154-1024x576.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-150154-500x281.jpg 500w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>Wire/crimp/solder:</p>
<p><a href="media/a6dce99d.P80802-155006.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-155006.jpg"><img class="aligncenter size-medium wp-image-2328" src="media/ab8b4113.P80802-155006-300x169.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-155006-300x169.jpg" alt="" width="300" height="169" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P80802-155006-300x169.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-155006-768x432.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-155006-1024x576.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-155006-500x281.jpg 500w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>Does work quite well:</p>
<p><a href="media/72538145.P80802-155928.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-155928.jpg"><img class="aligncenter size-medium wp-image-2329" src="media/374f3903.P80802-155928-300x169.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80802-155928-300x169.jpg" alt="" width="300" height="169" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P80802-155928-300x169.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-155928-768x432.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-155928-1024x576.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P80802-155928-500x281.jpg 500w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>With not much noise (static 100mA load):</p>
<p><a href="media/471572fb.NewFile1.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/NewFile1.png"><img class="aligncenter size-medium wp-image-2330" src="media/e3bd1cfa.NewFile1-300x180.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/NewFile1-300x180.png" alt="" width="300" height="180" srcset="http://www.dotmana.com/weblog/wp-content/uploads/NewFile1-300x180.png 300w, http://www.dotmana.com/weblog/wp-content/uploads/NewFile1-768x461.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/NewFile1-500x300.png 500w, http://www.dotmana.com/weblog/wp-content/uploads/NewFile1.png 800w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>And as I&#8217;ve this fancy portable solder iron with a bunch of li-ion cell:</p>
<p><a href="media/64caa645.P80803-213139.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80803-213139.jpg"><img class="aligncenter size-medium wp-image-2331" src="media/0ff5cab7.P80803-213139-300x169.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80803-213139-300x169.jpg" alt="" width="300" height="169" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P80803-213139-300x169.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P80803-213139-768x432.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P80803-213139-1024x576.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P80803-213139-500x281.jpg 500w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>
<p>It works on the road!</p>
<p><a href="media/91b86345.P80803-213225.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80803-213225.jpg"><img class="aligncenter size-medium wp-image-2333" src="media/a687588a.P80803-213225-300x204.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P80803-213225-300x204.jpg" alt="" width="300" height="204" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P80803-213225-300x204.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P80803-213225-768x523.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P80803-213225-1024x698.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P80803-213225-440x300.jpg 440w" sizes="(max-width: 300px) 100vw, 300px" /></a></p>


feed_id: http://www.dotmana.com/weblog/?p=2338
title: NASA workmanship standard pictorial reference (PDF)
uri: NASA-workmanship-standard-pictorial-reference-(PDF)
url: http://www.dotmana.com/weblog/2019/05/nasa-workmanship-standard-pictorial-reference-pdf/
content:
<p>The best assembly, rework, crimp, reflow, deadbug you name it standard.</p>
<p>You want to build stuff to last? Go to the moon? That&#8217;s the only way to go.</p>
<p>Here is the online version from NASA:</p>
<p><a href="https://workmanship.nasa.gov/lib/insp/2%20books/frameset.html">https://workmanship.nasa.gov/lib/insp/2%20books/frameset.html</a></p>
<p style="text-align: center;">And my home built PDF version:</p>
<p style="text-align: center;"><a href="media/c0cfd627.NASA_workmanship_standard_pictorial_reference.pdf" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/NASA_workmanship_standard_pictorial_reference.pdf"><img class="aligncenter size-medium wp-image-2339" src="media/5be120b4.COVER-246x300.gif" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/COVER-246x300.gif" alt="" width="246" height="300" />NASA_workmanship_standard_pictorial_reference.pdf</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2351
title: Dual Sim + micro-SD Hack
uri: Dual-Sim-micro-SD-Hack
url: http://www.dotmana.com/weblog/2019/08/dual-sim-micro-sd-hack/
content:
<p>Most dual sim smartphone don&#8217;t accept dual sim AND micro SD, but only ONE sim AND the micro-SD card.</p>



<p>This is definitely a bugger since mid range Android smartphone are pretty  stingy with storage memory (from 16Gb to 32Gb), while micro SD are pretty cheap an wayyyyy larger (128Gb to 512Gb)</p>



<p>Here is the hack to insert both dual sim, and a micro SD.</p>



<p>Tools needed</p>



<ul class="wp-block-gallery columns-2 is-cropped"><li class="blocks-gallery-item"><figure><img src="media/508191cf.P90814-094113-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-094113-1024x1024.jpg" alt="" data-id="2353" class="wp-image-2353" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-094113-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-094113-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-094113-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-094113-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-094113-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure></li><li class="blocks-gallery-item"><figure><img src="media/e7088abd.P90814-101315-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-101315-1024x1024.jpg" alt="" data-id="2363" data-link="http://www.dotmana.com/weblog/2019/08/dual-sim-micro-sd-hack/p90814-101315/" class="wp-image-2363" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-101315-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-101315-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-101315-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-101315-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-101315-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure></li></ul>



<p>Peel the back of the nanoSim plastic, with a hot air gun</p>



<figure class="wp-block-image"><img src="media/810aad7b.P90814-092749-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092749-1024x1024.jpg" alt="" class="wp-image-2354" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092749-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092749-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092749-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092749-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092749-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>Clip about 1mm the sides of the chip</p>



<figure class="wp-block-image"><img src="media/e0804781.P90814-092827-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092827-1024x1024.jpg" alt="" class="wp-image-2355" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092827-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092827-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092827-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092827-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092827-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>File the edge on the micro SD card</p>



<ul class="wp-block-gallery columns-2 is-cropped"><li class="blocks-gallery-item"><figure><img src="media/6e80d2a5.P90814-092547-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092547-1024x1024.jpg" alt="" data-id="2356" class="wp-image-2356" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092547-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092547-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092547-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092547-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092547-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure></li><li class="blocks-gallery-item"><figure><img src="media/c9f8e911.P90814-092612-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092612-1024x1024.jpg" alt="" data-id="2357" data-link="http://www.dotmana.com/weblog/?attachment_id=2357" class="wp-image-2357" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-092612-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092612-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092612-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092612-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-092612-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure></li></ul>



<p>Tape one side of the card tray</p>



<figure class="wp-block-image"><img src="media/13469c6f.P90814-093246-1024x758.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-093246-1024x758.jpg" alt="" class="wp-image-2358" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-093246-1024x758.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093246-300x222.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093246-768x569.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093246-405x300.jpg 405w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>Tape the other side (take care where the chip should align)</p>



<figure class="wp-block-image"><img src="media/2ef7b6f8.P90814-093517-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/P90814-093517-1024x1024.jpg" alt="" class="wp-image-2359" srcset="http://www.dotmana.com/weblog/wp-content/uploads/P90814-093517-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093517-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093517-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093517-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/P90814-093517-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>That&#8217;s it! Dual sim and lot of storage!</p>



<figure class="wp-block-image"><img src="media/44f439d4.S90814-094010-576x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/S90814-094010-576x1024.jpg" alt="" class="wp-image-2360" srcset="http://www.dotmana.com/weblog/wp-content/uploads/S90814-094010-576x1024.jpg 576w, http://www.dotmana.com/weblog/wp-content/uploads/S90814-094010-169x300.jpg 169w, http://www.dotmana.com/weblog/wp-content/uploads/S90814-094010-768x1365.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/S90814-094010.jpg 1080w" sizes="(max-width: 576px) 100vw, 576px" /></figure>


feed_id: http://www.dotmana.com/weblog/?p=2382
title: Flawed product design for prosumer: SumUp Air
uri: Flawed-product-design-for-prosumer-SumUp-Air
url: http://www.dotmana.com/weblog/2019/09/flawed-product-design-for-prosumer-sumup-air/
content:
<p>Don&#8217;t get me wrong, I love product design.</p>



<figure class="wp-block-image"><img src="media/17da0f07.Card_Acceptance_Animation_Reader.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Card_Acceptance_Animation_Reader.png" alt="" class="wp-image-2387" srcset="http://www.dotmana.com/weblog/wp-content/uploads/Card_Acceptance_Animation_Reader.png 700w, http://www.dotmana.com/weblog/wp-content/uploads/Card_Acceptance_Animation_Reader-150x150.png 150w, http://www.dotmana.com/weblog/wp-content/uploads/Card_Acceptance_Animation_Reader-300x300.png 300w, http://www.dotmana.com/weblog/wp-content/uploads/Card_Acceptance_Animation_Reader-144x144.png 144w" sizes="(max-width: 700px) 100vw, 700px" /></figure>



<p>Well defined product functionality implemented with mature and state of the art industrial process can yield very nice products.</p>



<p>But in some cases, pushing sleekness over function don&#8217;t deserve the product well. This is especially the case for prosumer product: professional consumer want sturdy, rugged product, surviving the field.</p>



<p>Even a sales person on a show with a tablet for demo want certain level of toughness: the tablet can be drop by the visitor, will be abused during storage and transport, etc..</p>



<p>Today I want to talk about SumUp Air: a small payment terminal, synced with your smartphone to accept payment over 3G/4G or Wifi.</p>



<p>The idea is great: use your smartphone to do the accounting/sales stuff, while having a dedicated card reader with pin input Bluetooth synced to hand to the customer.</p>



<p>But the implementation is very, very poor.</p>



<p>After few years of use, I found out the following issues:</p>



<ul><li>the device is BLE: it&#8217;s always on, advertising every 10sec: this sucks as if you have it in your car with your stock, it is a plain beacon and screaming to be broken in</li><li>the device cannot be switch off: yes, there is no way to switch it off. Contacting the support service, they told me you cannot even remove the battery as the signature/encryption key are in volatile memory (this is interesting as the battery must definitely be a li-po and can be over-discharged at some point)</li><li>the keyboard interface is tactile (capacitive sensors), customer have trouble typing the pin in as there is no feedback of the switch press: why using a tactile technology for this!</li><li>the front face is glass: just drop it and it will shatter: this is a field tool, the device WILL fall down, especially while handling it to customers, outdoors, etc..</li><li>Bluetooth wake up and pairing is just a pain: while it&#8217;s supposed to wake up when you start the transaction on your smartphone, most of the time it doesn&#8217;t: you can to re-enable discovery/pairing on the front of you customer</li><li>Location must be enabled on your smartphone: while this is interesting for transaction history, this is also a bad idea: it just drains the battery from your smartphone super fast.</li></ul>



<figure class="wp-block-image"><img src="media/eeef0b85.IMG_20190929_095352_2-1024x795.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095352_2-1024x795.jpg" alt="" class="wp-image-2384" srcset="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095352_2-1024x795.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095352_2-300x233.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095352_2-768x597.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095352_2-386x300.jpg 386w" sizes="(max-width: 1024px) 100vw, 1024px" /><figcaption>Tactile is not great for user feedback</figcaption></figure>



<figure class="wp-block-image"><img src="media/8230f874.IMG_20190929_095251-768x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095251-768x1024.jpg" alt="" class="wp-image-2385" srcset="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095251-768x1024.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20190929_095251-225x300.jpg 225w" sizes="(max-width: 768px) 100vw, 768px" /><figcaption>Yes, concrete floors always win</figcaption></figure>



<p> </p>


feed_id: http://www.dotmana.com/weblog/?p=2392
title: Marshall Kilburn, Kilburn II, Acton carry bag
uri: Marshall-Kilburn-Kilburn-II-Acton-carry-bag
url: http://www.dotmana.com/weblog/2019/10/marshall-kilburn-kilburn-ii-acton-carry-bag/
content:
<p>Just found the perfect bag for the awesome tiny portable Bluetooth speaker.</p>



<figure class="wp-block-image"><img src="media/aa31ad3e.dio_1002634_kilburn_ii_portable_bluetooth_1539601658_1436910.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/marshall_audio_1002634_kilburn_ii_portable_bluetooth_1539601658_1436910.jpg" alt="" class="wp-image-2394" srcset="http://www.dotmana.com/weblog/wp-content/uploads/marshall_audio_1002634_kilburn_ii_portable_bluetooth_1539601658_1436910.jpg 500w, http://www.dotmana.com/weblog/wp-content/uploads/marshall_audio_1002634_kilburn_ii_portable_bluetooth_1539601658_1436910-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/marshall_audio_1002634_kilburn_ii_portable_bluetooth_1539601658_1436910-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/marshall_audio_1002634_kilburn_ii_portable_bluetooth_1539601658_1436910-144x144.jpg 144w" sizes="(max-width: 500px) 100vw, 500px" /></figure>



<p>The <a href="https://www.reisenthel.com/en/allrounder-S.html">Reisenthel allrounder S </a></p>



<figure class="wp-block-image"><img src="media/20052656.m1_MR7003_pic1.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic1.jpg" alt="" class="wp-image-2393" srcset="http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic1.jpg 780w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic1-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic1-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic1-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic1-144x144.jpg 144w" sizes="(max-width: 780px) 100vw, 780px" /></figure>



<figure class="wp-block-image"><img src="media/91ce23f3.m1_MR7003_pic2.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic2.jpg" alt="" class="wp-image-2395" srcset="http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic2.jpg 780w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic2-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic2-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic2-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/m1_MR7003_pic2-144x144.jpg 144w" sizes="(max-width: 780px) 100vw, 780px" /></figure>



<figure class="wp-block-image"><img src="media/c083b8f1.IMG_20191011_172506-1-1024x769.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191011_172506-1-1024x769.jpg" alt="" class="wp-image-2398" srcset="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191011_172506-1-1024x769.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191011_172506-1-300x225.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191011_172506-1-768x577.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191011_172506-1-399x300.jpg 399w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<ul><li> Size (W x H x D):                 32 x 24,5 x 16 cm             </li><li> Volume:                 8 l            </li><li>Modeled after the traditional doctor’s bag: the contemporary interpretation of mobility!</li><li>Lightly padded lateral walls and bottom</li><li>Opening includes zip fastening and integrated metal bracket</li><li>6 inside pockets for practical storage</li><li>2 long carrying straps</li><li>Material: premium-quality polyester, water-repellent </li><li>Item no.: MR7003                  EAN: 4012013546136         </li></ul>


feed_id: http://www.dotmana.com/weblog/?p=2400
title: USB-C iron solder: TS100
uri: USB-C-iron-solder-TS100
url: http://www.dotmana.com/weblog/2019/11/usb-c-iron-solder-ts100/
content:
<p>TS100 is a very good iron solder, with a rated power of 17 to 65W, when powered from 12 to 24V.</p>



<p>While 12V DC jack DC5525 are everywhere, 24V are less but needed if you want more heat to solder larger components or grounds. (better than the TS-80 with the weak 18W anyway)</p>



<p>Supplying from USB-C source with PD 19V 60W takes full advantage of this iron solder.</p>



<p>This hack<a href="https://hackaday.com/2019/09/22/the-miniware-ts100-as-a-usb-c-soldering-iron/"> has been made</a> but not robust enough nor slick to my taste. </p>



<p><a href="https://www.aliexpress.com/wholesale?catId=0&amp;initiative_id=SB_20191107064654&amp;origin=y&amp;SearchText=90+degree+USB+3.1+USB-C+Type-C+bus+to+5.5*2.5mm+DC"> This 3 bucks USB-C to DC5.5mm @19V does the job.</a></p>



<figure class="wp-block-image"><img src="media/bb2624f4.usb-c_DC55_adapter.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/usb-c_DC55_adapter.jpg" alt="" class="wp-image-2401" srcset="http://www.dotmana.com/weblog/wp-content/uploads/usb-c_DC55_adapter.jpg 800w, http://www.dotmana.com/weblog/wp-content/uploads/usb-c_DC55_adapter-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/usb-c_DC55_adapter-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/usb-c_DC55_adapter-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/usb-c_DC55_adapter-144x144.jpg 144w" sizes="(max-width: 800px) 100vw, 800px" /></figure>



<figure class="wp-block-image"><img src="media/1f0e8507.IMG_20191106_213231-1024x768.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191106_213231-1024x768.jpg" alt="" class="wp-image-2402" srcset="http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191106_213231-1024x768.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191106_213231-300x225.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191106_213231-768x576.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/IMG_20191106_213231-400x300.jpg 400w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>Here a RAVPower 60W PD is used</p>



<figure class="wp-block-image"><img src="media/ad36d407.Filename-1024x768.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Filename-1024x768.jpg" alt="" class="wp-image-2403" srcset="http://www.dotmana.com/weblog/wp-content/uploads/Filename-1024x768.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/Filename-300x225.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/Filename-768x576.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/Filename-400x300.jpg 400w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>Perfect for my mobile bench with <a href="http://www.dotmana.com/weblog/2018/08/mini-portable-power-supply-diy/">the classic DPS3005 power supply.</a></p>


feed_id: http://www.dotmana.com/weblog/?p=2409
title: Industrial manufacturing: DFM or planned obsolescence
uri: Industrial-manufacturing-DFM-or-planned-obsolescence
url: http://www.dotmana.com/weblog/2020/04/industrial-manufacturing-dfm-or-planned-obsolescence/
content:
<p>I&#8217;ve stumble upon a fairly common appliance, present in most home, built by million of unit, a TV.</p>



<p>This model is a GRUNDIG 40VLE5324BG with LED backlight: not starting anymore (one could see the &#8220;Grunding&#8221; logo or &#8220;signal not present&#8221; when flashing a strong light on it).</p>



<p>After seeking the net for a solution, removing dozen of screws, accessing the 100cm long LCD panel made of ultra thin glass with COG and flex PCB on side, I finally had access to the culprit: No, it was not the capacitor, not the LED driver, not even a LED but a single connector: PCB to PCB connector, designed to decrease assembly time and cost. As these LED string are serial driven (140V @ 400mA), a single failure will render the whole system useless. </p>



<figure class="wp-block-image"><a href="media/e9712272.40VLE5324BG_led_failure.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure.png"><img src="media/be30b3ff.40VLE5324BG_led_failure-1024x782.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure-1024x782.png" alt="" class="wp-image-2412" srcset="http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure-1024x782.png 1024w, http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure-300x229.png 300w, http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure-768x586.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure-393x300.png 393w, http://www.dotmana.com/weblog/wp-content/uploads/40VLE5324BG_led_failure.png 1365w" sizes="(max-width: 1024px) 100vw, 1024px" /></a></figure>



<p>Just wiggling the connector would start/stop the backlight:</p>



<figure class="wp-block-image"><a href="media/49f2904c.Peek-2020-04-20-09-55.gif" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Peek-2020-04-20-09-55.gif"><img src="media/49f2904c.Peek-2020-04-20-09-55.gif" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/Peek-2020-04-20-09-55.gif" alt="" class="wp-image-2411"/></a></figure>



<p>In this case, slight flex, oxidation or poor connector plating cause the problem, and as the LED as serial connected, the connector is oxidized from long arcing:</p>



<figure class="wp-block-image"><a href="media/4dc9246b.20200419_155508.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/20200419_155508.jpg"><img src="media/deacd579.20200419_155508-768x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/20200419_155508-768x1024.jpg" alt="" class="wp-image-2410" srcset="http://www.dotmana.com/weblog/wp-content/uploads/20200419_155508-768x1024.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/20200419_155508-225x300.jpg 225w" sizes="(max-width: 768px) 100vw, 768px" /></a></figure>



<p>And the connector:</p>



<ul class="wp-block-gallery columns-1 is-cropped"><li class="blocks-gallery-item"><figure><a href="media/4ea92a76.20200420_102938-1024x768.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/20200420_102938-1024x768.jpg"><img src="media/4ea92a76.20200420_102938-1024x768.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/20200420_102938-1024x768.jpg" alt="" data-id="2415" data-link="http://www.dotmana.com/weblog/2020/04/industrial-manufacturing-dfm-or-planned-obsolescence/20200420_102938/" class="wp-image-2415" srcset="http://www.dotmana.com/weblog/wp-content/uploads/20200420_102938-1024x768.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/20200420_102938-300x225.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/20200420_102938-768x576.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/20200420_102938-400x300.jpg 400w" sizes="(max-width: 1024px) 100vw, 1024px" /></a></figure></li></ul>



<p>Let&#8217;s strap these connector with a piece of wire and fix this stuff!</p>



<p>Cheap 5ct clip will render a 500€/USD TV after few years! Hurray to planned obsolescence and global grow and economy!</p>


feed_id: http://www.dotmana.com/weblog/?p=2425
title: LED light flicker: DIY measure it
uri: LED-light-flicker-DIY-measure-it
url: http://www.dotmana.com/weblog/2020/11/led-light-flicker-diy-measure-it/
content:
<p>We all experienced it: light flicker! When concentrating on a piece of work or dead tree text, the light suddenly goes berserk and flash like a stroboscope on the dance-floor.</p>



<p>This effect is especially present in LED light fixtures where there is no inertia: incandescent or fluorescent light have a thermal or phosphor inertia and continue to glow a flick of second after the power is cut. But not the LED (even though there is some phosphor in them), this leads to have a close relation of the light intensity and the supply voltage.</p>



<p>Most of LED light bulb are supplied from main, the quality of the AC/DC converter takes a main role here. Because good rectification and filtering cost, manufacturer are cutting them, and you get this effect.</p>



<p>You can find two type of power supply on LED bulbs: simple rectification with LED string to match the AC rectified voltage. Or AC/DC converter with inductor and constant current control (this is what you want).</p>



<p>I wanted to &#8220;quantify&#8221; it, more that just a feeling, but didn&#8217;t want to drop hard cash (k€$ range) for dedicated equipment.</p>



<p>So I used one of the simplest and cheaper photo sensor on the market: a NPN phototransistor, (not a photoresistance as the bandwith is to small), in addition with a 10k resistor, connected to the GND (ring 2) and MIC (sleeve).</p>



<figure class="wp-block-image"><img src="media/6bd94967.light_flicker_jack-1024x768.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-1024x768.jpg" alt="" class="wp-image-2427" srcset="http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-1024x768.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-300x225.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-768x576.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-400x300.jpg 400w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<figure class="wp-block-image is-resized"><img src="media/332fb0d1.TRRS-Audio-Jack-Pinout.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/TRRS-Audio-Jack-Pinout.png" alt="" class="wp-image-2429" width="250" height="339" srcset="http://www.dotmana.com/weblog/wp-content/uploads/TRRS-Audio-Jack-Pinout.png 500w, http://www.dotmana.com/weblog/wp-content/uploads/TRRS-Audio-Jack-Pinout-222x300.png 222w" sizes="(max-width: 250px) 100vw, 250px" /></figure>



<p>Then use a simple Android software, called <a href="https://f-droid.org/en/packages/org.billthefarmer.scope/">Oscilloscope</a></p>



<figure class="wp-block-image"><a href="https://f-droid.org/en/packages/org.billthefarmer.scope/"><img src="media/a826af55.oscilloscope_fdroid.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/oscilloscope_fdroid.png" alt="" class="wp-image-2428" srcset="http://www.dotmana.com/weblog/wp-content/uploads/oscilloscope_fdroid.png 378w, http://www.dotmana.com/weblog/wp-content/uploads/oscilloscope_fdroid-300x82.png 300w" sizes="(max-width: 378px) 100vw, 378px" /></a></figure>



<p>The result is then very straightforward, especially in spectrum analyzer:</p>



<figure class="wp-block-image"><img src="media/576b565c.ceilling_office_panels_measure-768x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels_measure-768x1024.jpg" alt="" class="wp-image-2433" srcset="http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels_measure-768x1024.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels_measure-225x300.jpg 225w" sizes="(max-width: 768px) 100vw, 768px" /></figure>



<figure class="wp-block-image"><img src="media/96d56296.ceilling_office_panels-1024x485.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels-1024x485.jpg" alt="" class="wp-image-2430" srcset="http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels-1024x485.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels-300x142.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels-768x364.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/ceilling_office_panels-500x237.jpg 500w" sizes="(max-width: 1024px) 100vw, 1024px" /><figcaption>Standard office ceilling panels with AC/DC block converter under the drop down ceiling</figcaption></figure>



<figure class="wp-block-image"><img src="media/f99f8397.LED_COG.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/LED_COG.jpg" alt="" class="wp-image-2437" srcset="http://www.dotmana.com/weblog/wp-content/uploads/LED_COG.jpg 600w, http://www.dotmana.com/weblog/wp-content/uploads/LED_COG-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/LED_COG-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/LED_COG-144x144.jpg 144w" sizes="(max-width: 600px) 100vw, 600px" /></figure>



<figure class="wp-block-image"><img src="media/5016ea24.cheap_LED-1024x485.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/cheap_LED-1024x485.jpg" alt="" class="wp-image-2431" srcset="http://www.dotmana.com/weblog/wp-content/uploads/cheap_LED-1024x485.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/cheap_LED-300x142.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/cheap_LED-768x364.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/cheap_LED-500x237.jpg 500w" sizes="(max-width: 1024px) 100vw, 1024px" /><figcaption>Ultra cheap LED light bulb COG (chip on glass) with bridge rectifier (4 diodes)</figcaption></figure>



<figure class="wp-block-image"><img src="media/6d08568f.led_panel.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/led_panel.jpg" alt="" class="wp-image-2438" srcset="http://www.dotmana.com/weblog/wp-content/uploads/led_panel.jpg 588w, http://www.dotmana.com/weblog/wp-content/uploads/led_panel-300x210.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/led_panel-428x300.jpg 428w" sizes="(max-width: 588px) 100vw, 588px" /></figure>



<figure class="wp-block-image"><img src="media/751e3a68.studio_light-1024x485.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/studio_light-1024x485.jpg" alt="" class="wp-image-2432" srcset="http://www.dotmana.com/weblog/wp-content/uploads/studio_light-1024x485.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/studio_light-300x142.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/studio_light-768x364.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/studio_light-500x237.jpg 500w" sizes="(max-width: 1024px) 100vw, 1024px" /><figcaption>100€/$ photo studio panel with external AC/DC power supply or battery operated</figcaption></figure>



<p>I now always have this small 3.5mm 4 ring photo-transistor adapter in my pocket when shopping light bulb/appliances in home improvement, so I can point it and discard the worst devices.</p>



<p>If someone comes with a better idea, to measure more accurately amplitude and ideal the spectrum (would need a dedicated color sensor though), with an easy to use interface, that would be awesome.</p>


feed_id: http://www.dotmana.com/weblog/?p=2442
title: Interstellar OST: 15.7 kHz high pitched noise
uri: Interstellar-OST-15-7-kHz-high-pitched-noise
url: http://www.dotmana.com/weblog/2020/12/interstellar-ost-15735hz-high-pitched-noise/
content:
<p>Interstellar is an awesome movie, and the sound track is even better.</p>



<p>But after having listened it quite few times the original sound track, I quickly realize there is something wrong, not the <a href="https://en.wikipedia.org/wiki/Loudness_war">loudness war</a>, something worst: noise pickup during recording, not filtered out during mixing.</p>



<figure class="wp-block-image"><img src="media/662ff6fc.image.png" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/image.png" alt="" class="wp-image-2443" srcset="http://www.dotmana.com/weblog/wp-content/uploads/image.png 887w, http://www.dotmana.com/weblog/wp-content/uploads/image-300x121.png 300w, http://www.dotmana.com/weblog/wp-content/uploads/image-768x309.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/image-500x201.png 500w" sizes="(max-width: 887px) 100vw, 887px" /><figcaption>Track 06: Message from Home showing the 15735Hz peak at 51dB </figcaption></figure>



<p>Almost the complete album is tainted, for example, in this track, &#8220;Message from Home&#8221;, is a single piano recording showing this noise standing out clearely.</p>



<p>Dont get me started it&#8217;s because of the MP3 or format artifact, this is present on any version, MP3, FLAC, and even on Spotify online!</p>



<p>Here is an extract of this sound track, do you hear it? It hurts!</p>



<figure class="wp-block-audio"><audio controls src="media/627de247.06-Message-from-Home-extract-normal-speed.mp3" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/06-Message-from-Home-extract-normal-speed.mp3"></audio><figcaption>06 &#8211; Message from Home extract normal speed</figcaption></figure>



<p>If you cannot hear sounds around 16Khz, no problem, here pitched down version, to 0.5 with the noise is now at 8Khz if you don&#8217;t hear it, you may want to consult a specialist.</p>



<figure class="wp-block-audio"><audio controls src="media/f5c1ffcf.06-Message-from-Home-extract-half-speed.mp3" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/06-Message-from-Home-extract-half-speed.mp3"></audio><figcaption>06 &#8211; Message from Home extract half speed</figcaption></figure>



<p>Because it may sound crazy that a multi million dollar movie, OST and sound track composer (Hans Zimmer) get away with this, I&#8217;ve looked up and found this reddit thread mentioning it:</p>



<figure class="wp-block-embed-reddit wp-block-embed is-type-rich is-provider-reddit"><div class="wp-block-embed__wrapper">
    <blockquote class="reddit-card" >      <a href="https://www.reddit.com/r/audioengineering/comments/2mszh4/whats_up_with_this_spike_at_around_157khz_on_the/?ref_source=embed&amp;ref=share">What&#8217;s up with this spike at around 15.7kHz on the interstellar soundtrack? Only some tracks have it but damn does it hurt my ears :/.</a> from      <a href="https://www.reddit.com/r/audioengineering/">audioengineering</a>    </blockquote>    <script async src="https://embed.redditmedia.com/widgets/platform.js" charset="UTF-8"></script>
</div></figure>



<p>Well, I&#8217;m not crazy after all and it look like it&#8217;s a <a href="https://en.wikipedia.org/wiki/Pilot_signal">Pilot Signal</a> at &#8220;15.7342657 kHz is used to indicate the presence of <a href="https://en.wikipedia.org/wiki/Multichannel_television_sound">MTS</a> stereo.&#8221;</p>



<p>So that&#8217;s it, there is nothing to do, we are stuck with this (at least I can filter out my own version), but please, mixing engineers, next time, pay attention.</p>


feed_id: http://www.dotmana.com/weblog/?p=2456
title: UV-C lamp 3W USB power supply
uri: UV-C-lamp-3W-USB-power-supply
url: http://www.dotmana.com/weblog/2021/08/uv-c-lamp-3w-usb-power-supply/
content:
<p>Want to drive a E17 3W UV-C bulb (the germicidal one, generating ozone or not depending of the version of the glass) from USB (or any battery)?</p>



<figure class="wp-block-image"><img src="media/0f632831.HE1693445_185134-PHE-PHY-P01-1024x1024.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-1024x1024.jpg" alt="" class="wp-image-2457" srcset="http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>Use this DDTCCRUB 4S-2A Battery Charger Module Step Up Boost Li-Polymer</p>



<figure class="wp-block-image"><img src="media/4b11cc02.thium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50.jpg" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50.jpg" alt="" class="wp-image-2458" srcset="http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50.jpg 800w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-144x144.jpg 144w" sizes="(max-width: 800px) 100vw, 800px" /></figure>



<p>Change the RCS resistor from 50mOhm to 125mOhm (0.125 Ohm) to change the charging current to 300mA.</p>



<p>Remember, these bulb have to be supplied 16V (min) so the filament starts glowing, but once the arc is established, current has to be limited to 300mA (settling at around 10V)</p>



<figure class="wp-block-video"><video controls src="media/2a1fe14c.UV-C_USB.mp4" data-original-source="http://www.dotmana.com/weblog/wp-content/uploads/UV-C_USB.mp4"></video></figure>



<p>Don&#8217;t let it run more than few sec on the front of your naked eye/skin.</p>


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Fatal Error 63: CData section not finished

<p>We all experienced it: light flicker! When con
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		<title>UV-C lamp 3W USB power supply</title>
		<link>http://www.dotmana.com/weblog/2021/08/uv-c-lamp-3w-usb-power-supply/</link>
				<comments>http://www.dotmana.com/weblog/2021/08/uv-c-lamp-3w-usb-power-supply/#respond</comments>
				<pubDate>Wed, 04 Aug 2021 19:00:53 +0000</pubDate>
		<dc:creator><![CDATA[Tweepy]]></dc:creator>
				<category><![CDATA[Ubuntu]]></category>

		<guid isPermaLink="false">http://www.dotmana.com/weblog/?p=2456</guid>
				<description><![CDATA[Want to drive a E17 3W UV-C bulb (the germicidal one, generating ozone or not depending of the version of the glass) from USB (or any battery)? Use this DDTCCRUB 4S-2A Battery Charger Module Step Up Boost Li-Polymer Change the &#8230; <a href="http://www.dotmana.com/weblog/2021/08/uv-c-lamp-3w-usb-power-supply/">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
								<content:encoded><![CDATA[
<p>Want to drive a E17 3W UV-C bulb (the germicidal one, generating ozone or not depending of the version of the glass) from USB (or any battery)?</p>



<figure class="wp-block-image"><img src="http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-1024x1024.jpg" alt="" class="wp-image-2457" srcset="http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-1024x1024.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/HE1693445_185134-PHE-PHY-P01-144x144.jpg 144w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<p>Use this DDTCCRUB 4S-2A Battery Charger Module Step Up Boost Li-Polymer</p>



<figure class="wp-block-image"><img src="http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50.jpg" alt="" class="wp-image-2458" srcset="http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50.jpg 800w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-150x150.jpg 150w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-300x300.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-768x768.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/DDTCCRUB-chargeur-de-batterie-au-Lithium-3S-2A-Module-de-charge-de-batterie-Li-ion-Step.jpg_q50-144x144.jpg 144w" sizes="(max-width: 800px) 100vw, 800px" /></figure>



<p>Change the RCS resistor from 50mOhm to 125mOhm (0.125 Ohm) to change the charging current to 300mA.</p>



<p>Remember, these bulb have to be supplied 16V (min) so the filament starts glowing, but once the arc is established, current has to be limited to 300mA (settling at around 10V)</p>



<figure class="wp-block-video"><video controls src="http://www.dotmana.com/weblog/wp-content/uploads/UV-C_USB.mp4"></video></figure>



<p>Don&#8217;t let it run more than few sec on the front of your naked eye/skin.</p>
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		<title>Interstellar OST: 15.7 kHz high pitched noise</title>
		<link>http://www.dotmana.com/weblog/2020/12/interstellar-ost-15735hz-high-pitched-noise/</link>
				<comments>http://www.dotmana.com/weblog/2020/12/interstellar-ost-15735hz-high-pitched-noise/#comments</comments>
				<pubDate>Fri, 25 Dec 2020 20:02:51 +0000</pubDate>
		<dc:creator><![CDATA[Tweepy]]></dc:creator>
				<category><![CDATA[Audio]]></category>
		<category><![CDATA[Electronics]]></category>
		<category><![CDATA[Music]]></category>

		<guid isPermaLink="false">http://www.dotmana.com/weblog/?p=2442</guid>
				<description><![CDATA[Interstellar is an awesome movie, and the sound track is even better. But after having listened it quite few times the original sound track, I quickly realize there is something wrong, not the loudness war, something worst: noise pickup during &#8230; <a href="http://www.dotmana.com/weblog/2020/12/interstellar-ost-15735hz-high-pitched-noise/">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
								<content:encoded><![CDATA[
<p>Interstellar is an awesome movie, and the sound track is even better.</p>



<p>But after having listened it quite few times the original sound track, I quickly realize there is something wrong, not the <a href="https://en.wikipedia.org/wiki/Loudness_war">loudness war</a>, something worst: noise pickup during recording, not filtered out during mixing.</p>



<figure class="wp-block-image"><img src="http://www.dotmana.com/weblog/wp-content/uploads/image.png" alt="" class="wp-image-2443" srcset="http://www.dotmana.com/weblog/wp-content/uploads/image.png 887w, http://www.dotmana.com/weblog/wp-content/uploads/image-300x121.png 300w, http://www.dotmana.com/weblog/wp-content/uploads/image-768x309.png 768w, http://www.dotmana.com/weblog/wp-content/uploads/image-500x201.png 500w" sizes="(max-width: 887px) 100vw, 887px" /><figcaption>Track 06: Message from Home showing the 15735Hz peak at 51dB </figcaption></figure>



<p>Almost the complete album is tainted, for example, in this track, &#8220;Message from Home&#8221;, is a single piano recording showing this noise standing out clearely.</p>



<p>Dont get me started it&#8217;s because of the MP3 or format artifact, this is present on any version, MP3, FLAC, and even on Spotify online!</p>



<p>Here is an extract of this sound track, do you hear it? It hurts!</p>



<figure class="wp-block-audio"><audio controls src="http://www.dotmana.com/weblog/wp-content/uploads/06-Message-from-Home-extract-normal-speed.mp3"></audio><figcaption>06 &#8211; Message from Home extract normal speed</figcaption></figure>



<p>If you cannot hear sounds around 16Khz, no problem, here pitched down version, to 0.5 with the noise is now at 8Khz if you don&#8217;t hear it, you may want to consult a specialist.</p>



<figure class="wp-block-audio"><audio controls src="http://www.dotmana.com/weblog/wp-content/uploads/06-Message-from-Home-extract-half-speed.mp3"></audio><figcaption>06 &#8211; Message from Home extract half speed</figcaption></figure>



<p>Because it may sound crazy that a multi million dollar movie, OST and sound track composer (Hans Zimmer) get away with this, I&#8217;ve looked up and found this reddit thread mentioning it:</p>



<figure class="wp-block-embed-reddit wp-block-embed is-type-rich is-provider-reddit"><div class="wp-block-embed__wrapper">
    <blockquote class="reddit-embed-bq" style="height:240px" >      <a href="https://www.reddit.com/r/audioengineering/comments/2mszh4/whats_up_with_this_spike_at_around_157khz_on_the/">What&#8217;s up with this spike at around 15.7kHz on the interstellar soundtrack? Only some tracks have it but damn does it hurt my ears :/.</a><br> by      <a href="https://www.reddit.com/user/tomv92">u/tomv92</a> in      <a href="https://www.reddit.com/r/audioengineering/">audioengineering</a>    </blockquote>    <script async src="https://embed.reddit.com/widgets.js" charset="UTF-8"></script>
</div></figure>



<p>Well, I&#8217;m not crazy after all and it look like it&#8217;s a <a href="https://en.wikipedia.org/wiki/Pilot_signal">Pilot Signal</a> at &#8220;15.7342657 kHz is used to indicate the presence of <a href="https://en.wikipedia.org/wiki/Multichannel_television_sound">MTS</a> stereo.&#8221;</p>



<p>So that&#8217;s it, there is nothing to do, we are stuck with this (at least I can filter out my own version), but please, mixing engineers, next time, pay attention.</p>



<figure class="wp-block-image"><img src="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2023-04-12-10-18-35.png" alt="" class="wp-image-2464" srcset="http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2023-04-12-10-18-35.png 731w, http://www.dotmana.com/weblog/wp-content/uploads/Screenshot-from-2023-04-12-10-18-35-242x300.png 242w" sizes="(max-width: 731px) 100vw, 731px" /></figure>



<p></p>
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							<wfw:commentRss>http://www.dotmana.com/weblog/2020/12/interstellar-ost-15735hz-high-pitched-noise/feed/</wfw:commentRss>
		<slash:comments>2</slash:comments>
				<enclosure url="http://www.dotmana.com/weblog/wp-content/uploads/06-Message-from-Home-extract-normal-speed.mp3" length="922893" type="audio/mpeg" />
<enclosure url="http://www.dotmana.com/weblog/wp-content/uploads/06-Message-from-Home-extract-half-speed.mp3" length="922893" type="audio/mpeg" />
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		<title>LED light flicker: DIY measure it</title>
		<link>http://www.dotmana.com/weblog/2020/11/led-light-flicker-diy-measure-it/</link>
				<comments>http://www.dotmana.com/weblog/2020/11/led-light-flicker-diy-measure-it/#comments</comments>
				<pubDate>Sat, 07 Nov 2020 12:50:03 +0000</pubDate>
		<dc:creator><![CDATA[Tweepy]]></dc:creator>
				<category><![CDATA[Ubuntu]]></category>

		<guid isPermaLink="false">http://www.dotmana.com/weblog/?p=2425</guid>
				<description><![CDATA[We all experienced it: light flicker! When concentrating on a piece of work or dead tree text, the light suddenly goes berserk and flash like a stroboscope on the dance-floor. After fixing a TV with LED backlight, let&#8217;s dive in &#8230; <a href="http://www.dotmana.com/weblog/2020/11/led-light-flicker-diy-measure-it/">Continue reading <span class="meta-nav">&#8594;</span></a>]]></description>
								<content:encoded><![CDATA[
<p>We all experienced it: light flicker! When concentrating on a piece of work or dead tree text, the light suddenly goes berserk and flash like a stroboscope on the dance-floor.</p>



<p>After fixing a <a href="http://www.dotmana.com/weblog/2020/04/industrial-manufacturing-dfm-or-planned-obsolescence/">TV with LED backlight</a>, let&#8217;s dive in different performance of light fixture/light bulbs.</p>



<p>This effect is especially present in LED light fixtures where there is no inertia: incandescent or fluorescent light have a thermal or phosphor inertia and continue to glow a flick of second after the power is cut. But not the LED (even though there is some phosphor in them), this leads to have a close relation of the light intensity and the supply voltage.</p>



<p>Most of LED light bulb are supplied from main, the quality of the AC/DC converter takes a main role here. Because good rectification and filtering cost, manufacturer are cutting them, and you get this effect.</p>



<p>You can find two type of power supply on LED bulbs: simple rectification with LED string to match the AC rectified voltage. Or AC/DC converter with inductor and constant current control (this is what you want).</p>



<p>I wanted to &#8220;quantify&#8221; it, more that just a feeling, but didn&#8217;t want to drop hard cash (k€$ range) for dedicated equipment.</p>



<p>So I used one of the simplest and cheaper photo sensor on the market: a NPN phototransistor, (not a photoresistance as the bandwith is to small), in addition with a 10k resistor, connected to the GND (ring 2) and MIC (sleeve).</p>



<figure class="wp-block-image"><img src="http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-1024x768.jpg" alt="" class="wp-image-2427" srcset="http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-1024x768.jpg 1024w, http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-300x225.jpg 300w, http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-768x576.jpg 768w, http://www.dotmana.com/weblog/wp-content/uploads/light_flicker_jack-400x300.jpg 400w" sizes="(max-width: 1024px) 100vw, 1024px" /></figure>



<figure class="wp-block-image is-resized"><img src="http://www.dotmana.com/weblog/wp-content/uploads/TRRS-Audio-Jack-Pinout.png" alt="" class="wp-image-2429" width="250" height="339" srcset="http://www.dotmana.com/weblog/wp-content/uploads/TRRS-Audio-Jack-Pinout.png 500w, http://www.dotmana.com/weblog/wp-content/uploads/TRRS-Audio-Jack-Pinout-222x300.png 222w" sizes="(max-width: 250px) 100vw, 250px" /></figure>



<p>Then use a simple Android software, called <a href="https://f-droid.org/en/packages/org.billthefarmer.scope/">Oscilloscope</a></p>



<figure class="wp-block-image"><a href="https://f-droid.org/en/packages/org.billthefarmer.scope/"><img src="http://www.dotmana.com/weblog/wp-content/uploads/oscilloscope_fdroid.png" alt="" class="wp-image-2428" srcset="htt


