1. if ordering rotary switches from Digikey, most of the ones they stock are adjustable (even if marked as fixed in the product description), so if the switch doesn’t seem to rotate to all of the positions, try taking the nut off and removing the index washer. I just received two supposedly “fixed-index” 12 pole switches which only rotated to 11 positions. Turns out they were actually adjustable and worked fine.

  2. tip: Young people (under 18, in the EU) who want to create a paypal account for your enterprising businesses or other fun activities: before your 18th birthday, ONLY create accounts with disposable email addresses. Once your account gets credited with more than €2500 in one financial year, Paypal have to do an identity verification check, and when they find out you created an account before you were 18, they freeze it, and you have to create a new account with a new email address.

  3. : if you don’t like the new OSX Photos app and don’t want it opening when you plug your iDevice in, plug in the device, open Image Capture, make sure this thing is showing:

    and select the option you want (Photos, iPhoto, Image Capture, nothing)

  4. for anyone using QtMultimedia QAudioInput with python’s wave module to write PCM data to a wave file: to convert between QAudioFormat’s sampleSize() number and wave’s sample width number, divide by 8, e.g:

    wave_file_to_write.setsampwidth(audio_format.sampleSize() / 8)

    QAudioFormat’s sampleRate() number works as it is.

  5. tip: if you come across weird inconsistencies between apps when trying to serve static files in dev, run with runserver --insecure even if you have DEBUG=True

  6. git grep is pretty amazingly fast — get line numbers too with -n or git config --add grep.lineNumbers true

  7. : Use <form action="." method="post"> for RESTful /collectionname/new forms if collectionname cannot be hard–coded. Saves loading backend routing config into the front end when it’s not required