Adventures of a Tech, avonturen van een techneut

A few days ago I started playing with OnShape, an online design program. It can do a lot of things and I am very impressed by it. Check it out at https://www.onshape.com/ I designed a mounting bracket for my camera microscope (which needs to mount on my spindle motor) In 3D it looks like this  And after exporting the contour as a DXF file I milled it on my CNC machine. I used a 4 mm 2 flute end mill, at 20000 rpm. The mill had to stick out quite a lot, so I have some shatter markings on the surface, but it worked, milling 20 mm thick aluminium. The results are here. Impressive right ? Until next time, Greetings from Holland ;-)

Today I repaired my laptop. It was not working anymore, completely dead. Here is a link to the manufacturer : http://www.msiwhitebook.com/product_spec.asp?model=MS-1035 It is an old one, it does not support Virtualbox, but runs Debian just fine. I like it because it has a 17" screen, nice to work in bed, full size keyboard too. Searching for problems without any schematic is just gambling so I postponed it. I found a YouTube channel by Louis Rossmann who repairs laptops, https://www.youtube.com/channel/UCl2mFZoRqjw_ELax4Yisf6w and he got some schematics from a website : laptop-schematics.com I ordered my schematics for about 10 euro. I got 57 pages of PDF. I had to take apart the whole laptop to get near the actual hardware. I took my time, did not break any plastic tabs off.. And after what seemed like an hour I was where I needed to be. I started at the beginning, the power input and verified it. 19.14 volts. At the end of the ...

Today I repaired a parking sign. Why? Because I need to have an excuse to use my CNC milling machine, that is why! I drew the sign with Q-Cad professional ( http://www.ribbonsoft.com/shop/ ) and imported it into USBCNC. I used a 2 flute 4 millimeter end-mill and created a couple of P characters. Do you want to make one too : here is the DXF file , have fun.

Today I repaired a Samsung TV in just a few minutes. A friend walks in and says : My Samsung TV is ticking.. Red light blinking on/off... It is about 6 years old... What could it be? I just say : "Ah bad caps again?" Reply : "Do you really thinks so?" Let's fix this puppy a.s.a.p so you can watch TV again. So I take my screw driver and go with him to take a look at the TV. Indeed, it is trying to start but fails etc. tick tick tick blink blink blink... 1) remove power cord 2) take off back cover 3) look around 4) Notice caps with round caps in PSU??? Of course there are, 2 bad capacitors, 10 Volt 1000uF close to a thermal aluminium block. Alright, here they are... I say.. Exclamation : "Bad caps again? Can they not make anything anymore without bad capacitors, I bet most of these TV's get dumped in the trash for this" And that is probably true, a bad capacitor costing 20 cent will make your TV worthles...

Today I figured it out. What did you figure out, I hear you say... I finally resolved a problem with a USART on a STM32F407 board, that was easy to spot if I had just looked closely. I just lost a day in trying to find the fault. I am working with this board made by Olimex (https://www.olimex.com/Products/ARM/ST/STM32-E407/open-source-hardware) And connected it using ST-Link interface to my PC. I connected the SWD pins to the JTAG connector of the Olimex SWD-pin-1 ------ JTAG-pin-1 (VCC) SWD-pin-2 ------ JTAG-pin-9 (TCK) SWD-pin-3 ------ JTAG-pin-4,6,8 (GND) SWD-pin-4 ------ JTAG-pin-7 (TMS) SWD-pin-5 ------ JTAG-pin-15 (TRST) SWD-pin-6 ------ JTAG-pin-13 (TDO) I connected the serial port (USART6 is pins 3 and 4 of UEXT) of the Olimex to the TX/RX lines of the ST-link (see the green circle) Then I wrote a program and tested it. I made sure the PLL of the STM32F407 was running, configured all the needed files. defined the target cpu in stm32f4xx.h (...

Currently I am working on an alternative controller for AutoJet Technologies Spray controller made by Spray systems Inc. http://www.spray.com/spray_nozzles/pulsajet_nozzles.aspx I have been working on a more advanced and microprocessor controlled controller, it is intended to be used where the Model 1008 (AutoJet PWM driver modules, aka CP-PMDCT1008-XX) are not advanced enough or easy enough to install and set up. The 1008-AutoJet device is a pure analog box, it needs to be programmed with potentionmeter/trimmer inside the device and can be controlled externally using industry standard 0..20mA current loop to control frequency of pulses. The typical application I am looking at is the airless deposition of oils or emulsions used in the production of concrete products. The oils or emulsions are used as releasing agents with high viscosity, mould release agents designed for the production of expanded concrete blocks.  Deposition with air-driven nozzles leads to inaccu...

It has been far too long since I wrote something on my blog. I have been writing on another site : http://blog.wisclub.nl/#home about my CNC machine, and about the mcHF transceiver I am building. Today I ran into a little problem after updating some packages on my Ubuntu 12.10 VM. (I know this is very old, but I have no choice since a vendor supplied a gcc/uclib toolchain for a specific product exactly on this version of Linux) However, my X did not start anymore, I got "Failed to load session gnome". After some digging I realized what had happened, the default X session was set to gnome (which is not really installed) instead of my normal XFCE4 session. If you know what the problem is, the fix is easy : $ sudo update-alternatives --config x-session-manager Then select the correct session manager. I hope this helps someone from having to search a long time. Until next time.

I have been working on my CNC milling machine and tested the new stepper motor controllers last Friday 13th. Brand new controller, power supply made of a large toroidal transformer, large diode bridge and lots of parallel capacitors made a very strong 42 volt. http://www.omc-stepperonline.com/4-axis-tb6600-cnc-stepper-motor-driver-controller-board-for-cnc-router-milling-p-309.html After the smoke cleared... I investigated the source of the problem. This was not a fault I made in wiring, nope... The exploded capacitors were 220uF/16 Volt types parallel to the power supply of 42 volt... Not a real surprise that they did not last 2 seconds. I do not think it is very hard to build a good CNC stepper board, but some engineers or buying departments still struggle with the basics like capacitor voltage specification. After removing the exploded capacitors we managed to get the motor controller working without problems (without the caps) The CNC machine now moves all Axis...

I got a DDS with a serial interface https://bitbucket.org/tweetand/udb120x/overview You can now control the device over a serial/USB port if you want. Use my code, original research.

De F-licentie is behaald, paar weken geleden examen gedaan. Met dank aan  http://www.radio-examen.nl/  (Stichting radio examen) voor het organiseren. Dit betekent dat ik nu officieel mag spelen met radio-zenders. (uit wikipedia) Met  radioamateurs  of  zendamateurs  (of in officiële terminologie  radiozendamateurs ) worden in brede zin personen bedoeld die zich voor hun  hobby  bezighouden met experimenteren op het gebied van het uitzenden en ontvangen van  radio - en/of  televisiesignalen . Hiervoor hebben zij de beschikking over een officiële  zendvergunning . Deze zendvergunning wordt door de overheid toegekend na het slagen voor een officieel examen, waarbij, afhankelijk van het gewenste vergunningsniveau, het kennisniveau met betrekking tot radio-elektronica en regelgeving getoetst wordt. Voor wie meer wil weten : VERON de Vereniging voor Experimenteel Radio Onderzoek Nederland Update : mijn officiële registratie ...

Ok, even een niet technisch verhaal. Voor mezelf en een paar knutselvriendjes heb ik een paar T-shirts besteld bij TEESpring http://teespring.com/NegativeFeedbackBlack  om Dave Jones en zijn EEVBlog te steunen. De T-shirts kosten 15 dollar per stuk, dat is in Euro's : 12,11 per stuk. Prima prijsje. Voordat je dit in huis hebt zit je met shipping : 20 dollar, en dan komt de BTW (21 %) en de afhandelingskosten (waarvoor PostNL je dan 13,00 euro rekent, dus meer dan de waarde van je T-shirt) Ondertussen ligt je T-shirt dus bij de inklaring...  weer weekje verder... Ik snap dat niet helemaal, als je namelijk iets uit China laat komen kost dat helemaal niks. Dat snap ik ook niet, hoe kun je nu iets opsturen met Free Shipping en dan is het er toch na een week? Ik snap er eigenlijk helemaal niks van. Onze postbode moet ook betaald worden, ook al zijn alle echte postbodes ontslagen en nu vervangen door huismoeders die de kinderen net op school hebben afgezet. (als postbo...

Theo Kleijn has his laser cutter setup and it was time to make something useful. Theo's blog :  http://pa0kn.nl/#home I took a board I had laying around, a 16 relay board, similar to one found here :  http://www.ebay.com/itm/16-Channel-12V-Relay-Module-Coupling-Optocoupler-High-Trigger-For-MCU-Arduino-/221358546298 and  http://www.miniinthebox.com/16-channel-12v-relay-module-board-w-power-lm2576-optocoupler-protection_p903439.html And decided to make a nice base for it, so it was not directly on the table. I started by designing the base plate, I measured the board and made a drawing in LibreCad, which was in the Ubuntu repository. This was not a success, when trying to save the file the program segfaulted and all my work was lost. I already had a license for QCAD 2.2 (on which LibreCad is based) and have used it without problems on my old linux machines (in 2008 and later). The old version I had was alright, many productive shortcut-keys etc, but many impr...

My sister came walking in with her small Sony Radio/Cassette/CD-player. Of course there was a problem with this device The volume control was not working, when at "0" it would mute, but at low level it would just go too loud. Luckily I found a schematic online : http://diagramas.diagramasde.com/audio/HCD-EP30%20EP40%20sm.pdf After some investigation I figured out that the LC75392 was in control of the volume http://pdf.datasheetcatalog.com/datasheet/sanyo/ds_pdf_e/LC75392.pdf I traced the problem to the main circuit board and started measuring all the voltages (given in the schematic) and they appeared to be all right. I then used my new audio-sniffer to track the audio from the radio receiver. http://www.openmusiclabs.com/projects/audio-sniffer/ This is where I got one from Santa-Claus. Some example of someone else tracking a signal with the audiosniffer here on YouTube. http://www.youtube.com/watch?v=ZxUItbtYl_0 I noticed that I was getting a l...

Het heeft even geduurd voordat ik het snapte (en nu vind ik het nog een vreemd concept) maar ik heb ondertussen bitcoins. Ik heb uitgevogeld hoe je een wallet maakt, hoe je er geld op zet en nog wat details. Het lijkt ingewikkeld maar is dat dus helemaal niet. Ik gebruik Armory (https://bitcoinarmory.com/) dat samenwerkt met bitcoin-Qt (https://bitcoin.org/en/download) Via https://bitonic.nl/ en https://bitmymoney.com heb ik wat transacties gedaan en dat werkte vlekkeloos. Wat me vooral opviel was dat je ontzettend lang moet synchroniseren voordat je aan de slag kan, heb geduld, trek hier gerust een nachtje voor uit, daarna loopt het snel. Als je geld via Ideal overmaakt naar je bitcoin adres staat het er binnen een paar minuten op. My public wallet address is :  1DynDMhxWweJr6aoSZXUzenJMkSjaWHGxo  you can send donations there. Dus als u mij geld wil sturen mag dat op adres :  1DynDMhxWweJr6aoSZXUzenJMkSjaWHGxo Bij voorbaat dank, :-)