Raspberry Pi + Cantenna: Ultimate 2.4GHz Wardriving and Long-range WiFi Access

Want to turn your Raspberry Pi into a portable antenna / wireless router that can be used to pick up WiFi signals from great distances?  I did.  I will walkthrough how to make the 2.4GHz cantenna using some cheap components and then setup the Pi as a router so you could search for WiFi access points, connect to them, and potentially relay the signal. Great for wardriving or just connecting to your home Wi-Fi from out in the backyard. Continue reading “Raspberry Pi + Cantenna: Ultimate 2.4GHz Wardriving and Long-range WiFi Access”

Automator: Scale Down Large Images From the Contextual-menu

Automator seems to be one of those unknown or ignored Apple-made apps.  But it is very powerful and can save you a lot of time.  It has also been part of OS X for a long time.


To save time by automatically scaling down images (while keeping the original file) to a pre-set size as opposed to manually editing each one.

Requirements For This Walkthrough


  1. Mac with OS X
  2. Large image files


  1. Automator workflow

Knowledge, Skills, and Abilities

  • Ability to navigate throughout a computer OS
  • Knowledge of basic computer terminology

Step-by-step Instructions

Create the Automator Workflow

You can also download a a pre-built workflow.

  1. Create a folder for the scaled-down images to go
  2. Open /Applications/Automator
  3. Create a workflow similar to the following: (editing the folder and size fields)jacob_salmela_automator_workflow_reduce_image
  4. Click File > Save
  5. Save as something like Reduce to 800×600

Use The New Contextual Service

  1. Right-click a large image file
  2. Click Reduce to 800×600jacob_salmela_resize
  3. Watch the magic happen

The scaled-down image will now be revealed in the folder you designated.  The original remains in-tact.  This operation can also be completed on many files at once.  In this example, the picture was 1.8MB and was reduced to 144K.

Wi-Fi Cantenna (2.4GHz): How-to Make a Long-range Wi-Fi Antenna

Create a cantenna to drastically extend your Wi-Fi signal!  Works great with a router that has external atennas, like the old-school classic WRT54G. Continue reading “Wi-Fi Cantenna (2.4GHz): How-to Make a Long-range Wi-Fi Antenna”