PONG… I’m online and answering again…

I did not post anything for quite a while… we bought a house and moved into it. This consumed most of my spare time and my ‘hacking capabilities’ during the last few months. But the good news is: I’ve now got a whole room in the cellar which I’m currently turning into a hacker lair / electronics shop without having to care too much about the the WAF.

I just just returned from a business trip to the US and wanted to ‘report back’ with a nightly impression of New York / Manhattan. (Please forgive the low quality as the photo was taken with my smartphone from the airplane window.)

RANT: Do not misuse spreadsheets for data storage

Using spreadsheet files for data storage and exchange can lead to the
corruption and even loss of information — sometimes without noticing it immediately. I came across this one too often so┬áI could not help but┬áwrite a┬árather long post about this topic.

Sharing datasets with other researchers┬áor┬ácollaboration partners is a vital part of the knowledge┬áexchange in a┬ácommunity. This might happen in big scale in form of┬ásupplementary material along with publications or in small scale within┬áresearch groups. In this post┬áI do not want to focus on what is actually┬áshared, but how. Because a crucial but commonly underestimated element when┬ásharing datasets with others is the used data format. Continue reading “RANT: Do not misuse spreadsheets for data storage”

Aliexpress search customization and optimization (via hidden sort options in the URL)

About a year ago┬á(2016) Aliexpress decided to cripple simplify their search engine. They’ve removed really useful search options and added (at least in my eyes) unnecessary ones.

These useful search options were removed from the search panel but they are still available as URL parameters. I’ve mainly written this post to document these missing options for my everyday searches┬á— but┬áI’m pretty sure others may find them useful as well.

Aliexpress Hidden Search Options
Option Value Description
isUnitPrice y Show Price per Piece
minQuantity number Minimal Quantity in Lot
maxQuantity number Maximal Quantity in Lot
isFreeShip y Free Shipping only
sortType price_asc/price_desc Ascending/Descending Prices

Especially the option isUnitPrice is helpful when searching for the best price per piece and not price per lot.

So when I’m searching for the lowest price per piece within a certain quantity range (here: 10 – 50 pieces) with free shipping I would add to the URL (Example Search):

&minQuantity=10&maxQuantity=50&isUnitPrice=y&sortType=price_asc&isFreeShip=y

Side Note: It also makes a difference which keywords you are using when searching. The following three searches will (at least the last time I’ve checked) give different results:

  • “stm32f103c8t6 lqfp
  • “stm32f103c8t6 lqfp48
  • “stm32f103c8t6 lqfp-48

So even slight variations can make a big difference. Unlike the search on eBay, the search on Alibaba and Aliexpress does not split up keywords into smaller ‘chunks’ which are used for searching.

Started to build my Raspberry Pi PiDrive System (for RetroPie)

I’ve started to rework my Raspberry Pi ‘dial-up’ interface. Instead of just handling my external VPN and SSH connections┬áI’ve extended it to also function as an intermediate file server and Git repository (both via NFS+SSH). I’ve also inserted the Raspberry Pi into a new case and added a 1 TB 2,5″ drive. I think it┬ácan handle additional load so I plan to extend its capabilities to also serve as a RetroPie console.

By the way: the case and the connector cable between the drive and the Pi are both from WD Labs. The hard drive is not a PiDrive but a refurbished USB 3.0 1 TB disk┬á(it was a recertified My Passport Ultra) before I’ve dismantled┬áit. For me it was cheaper that way. If you’re looking for a similar setup and need an additional power supply and SD card maybe you should think about buying a Nextcloud Box┬á(free shipping;┬áhandled by WD). You might┬ánot need to use its ‘cloud’ functionality but still get all hardware I’ve previously mentioned which I think is a┬ápretty good bargain.

USB Infrared Toy (Dangerous Prototypes) free PCB build

I finally completed the free USB IR Toy v3 PCB I got over a year ago (May 2015) from Dangerous Prototypes.

It took so long because I had to┬áorder some of the parts from Digi-Key – and I┬áwanted to wait until I’ve a longer list of parts to order.
I’ve used a PicKit 3 to program the PIC microcontroller. The trickiest part was finding the setting┬áto power the USB IR Toy with the programmer. (I could have powered both devices via USB, but only had one appropriate cable at my hand at that time.)

usb-ir-toy-programming-verification

So far I’ve only verified that the USB IR Toy is detected as serial device and shows its version number in a terminal window. It looks like the build was successful… ­čÖé

usb-ir-toy-terminal-v222

Kids + Railway Toilets = Toilet-Blinkenlights…

Today my kids impressed me by repurposing/hacking/misusing the toilet-occupied-light to send (morse-like) signals across a railway car. Their fingers were thin enough to press the micro-switches in the doors which normally would signal a locked door (i.e. occupied toilet). Not sure if someone noticed the strangely flashing lights… ­čśÇ

railway-toilet-door