• Home Improvement

    What’s with these weak-ass DC garage door motors these days?

    If you’re DC motor garage door opener seems weak, either your door is too heavy or the springs are past half their life. Be prepared to shell out some dough.

    If you’ve been in the market for a garage door opener in the past 5 years or so, you may have noticed the switch from AC motors to DC motors. Manufacturers like Chamberlain (Liftmaster/Craftsman) market the DC motor openers as “Ultra-Quiet” versus just “Quiet” of the old.

    The 2018 California SB 969 mandates that new garage door openers are available with battery backup – that necessitates the motors to work on DC power off of a battery. The rest of the country gets to enjoy the benefits and pitfalls of this new device at their own leisure.

    Yes, DC motors are quiet, especially if they are paired with a belt drive instead of the traditional chain drive mechanism. No clanking, no buzzing, no thunk at the start and end of the cycle. The AC/DC inverter (transformer)  quietly supplies constant steady power to the drive system. 

    But because it doesn’t draw its power directly from the house’s AC circuit, it will not answer to demand. That means, if the the springs on the door gets old and weak, you’ll notice the door slow down. If you’re an installer, you’ll also find out the hard way that the motor will not be able to assist you when lifting the door under a broken spring. 

    This is not because the motor itself is weak. It is because the motor is not allowed to draw more current from the house because there’s a DC inverter playing gatekeeper. It is in theory a safety mechanism that prevents problematic doors from being lifted and then falling on a person. The controller board should register an error and cease to function until the problem is remedied.

    Unfortunately there is an unintended effect. In case of a broken spring, the door will move a smidge under extreme load and damage the motor control unit – not the physical motor, but a small gearbox and circuit board attached to the motor.

    In an effort to make safer more quieter garage door openers, manufacturers have complicated the design of these units and made it more difficult to diagnose and fix. Fortunately, we have the internet, so we can sit at a desk and search instead of tinkering with the greasy innards of the garage door motor.

    The easiest solution for manufacturers would probably be to increase the motor current to 24V and put two 12V batteries in there…

  • Uncategorized

    That Mac script that passes MP4v to ffmpeg

    Because of how Mac OS Mojave, Big Sur, Monterey handles file permissions, many Firefox add-ons are not able to pass downloaded files to outside binaries. Usually, the add-on will return a “file/directory not found” or “permission” error.

    I use one such add-on that converts movies to audio-only so that I can listen to a video in a car. After the upgrade to Mojave, the add-on started having problems with passing the downloaded MP4 file to ffmpeg to convert into M4A (MP4 Audio). So instead of typing commands into the Terminal to pass the file to ffmpeg, I decided to make an Automator script to convert MP4 to M4A from contextual menu by right-clicking on the file

    1. In Automator create a new Quick Action
    2. Make the item shown below. I usually keep the ffmpeg executable in ~/bin
    3. Save the script
    4. Name it Convert MP4 to M4A

    That’s it. Now you can right click on a MP4 file and call up the conversion script from the Quick Action or Services item.

    This script is meant for people who know what they’re doing. It won’t check if the file you’re trying to convert is an actual MP4 file, and it won’t display any errors to the GUI. Use with caution.

  • Uncategorized

    How do I unlink my Facebook account from the McDonalds mobile app?

    Short answer: At the time of this article (Dec 2021) YOU CANNOT.

    You can’t even change your e-mail address with the McDonalds app even if you signed up using your e-mail address only.

    According to the official McDonalds Mobile Order app help page: https://www.mcdonalds.com/us/en-us/mcdonalds-app/faqen.html

    Can I change the Email Address? No.

    I suspect that the developers for McD decided to use the e-mail/login-method as the primary unique key for each user instead of assigning a number for the userID. Kind of ridiculous. If you get fired from work or graduate from school, your e-mail address is going to change. If you move from Meta to Google, your login method is going to change. McDonalds expects each customer to possess a “for-life” e-mail address to be using the mobile app.

    I hope this changes in the future because it is totally do-able technically and makes sense practically.

  • Tech

    Downloaded iTunes/Music track is twice as long

    If you’ve downloaded music tracks from a video source, there is a chance that your software did not pass the correct parameters to the audio converter. This is the case with a certain Firefox extension YT downloader that passes the files to ffmpeg. The music track contains extra space for the non-existent video and the track time is twice as long. iTunes/Music.app has a bug where it will play the next track during this blank time, therefore, the CoverArt and Title will not change while the next song plays. You will need to reattempt to convert the files from MP4 to M4A manually or some kind of automated/batch method.

    The correct parameters are:

    ~/foo/bar/bin/ffmpeg -i %input -acodec copy -vn %output

    You can set up an Automator process as a Service so you have it under the Contextual menu when you Right-click, or you can set up the download folder for YT Downloader to be the target for a Automated process where the MP4 is converted to an m4a, then added to the iTunes/Music.app directory automatically.

  • Tech

    iOS 14.x Duplicate Songs in Downloaded Music

    If you see a bunch of duplicate songs in the “Downloaded” playlist in your iPhone Music.app, then there is a chance that you have manually dragged music files to your iPhone icon in iTunes or Finder to add them to the Library before Apple made a change in how these music files were marked. You will need to delete these music files from the iPhone to get rid of duplicates. This can be done by un-sync-ing your Music, deleting all Downloaded music, then re-sync-ing.

    1. Connect your iPhone to your Mac
    2. On the Mac, open a Finder window, select your iPhone from the left pane
    3. In the right pane, select the Music pane
    4. Un-check “Sync music onto… iPhone”
    5. Click “Sync” on bottom right; All sync’ed music should disappear from your iPhone
    6. On the iPhone, Go to Settings > General > iPhone Storage
    7. Swipe “All Music” to the left and delete all the music that is Downloaded to your phone; Now you should only have music tracks you’ve purchased from the iTunes Music store that are on the cloud
    8. On the Mac, go back to the Finder window with the Music pane
    9. Check “Sync music onto… iPhone”
    10. Click “Sync” on the bottom right; All or Selected music will be transferred back to the iPhone

    Now there’s going to be a problem if you downloaded music to the iPhone from another source, like another Mac. But if you were smart enough to do that, you can probably think of how to get around it.