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Script for Finding the Best WiFi Channel

When running a wifi router in a public space, the least congested channel will offer the best performance. Use this script for Apple computers to help you find that channel fast.

For live sound events I often use wifi to interact with computers and digital devices that control audio, video, and lighting. Having dedicated, reliable wifi is critical for successful productions, so I bring my own router with me to live events. This is the model I own and recommend.

image of TP-Link router

All your [wifi] base belong to us.

WiFi is has become nearly ubiquitous. Networks are everywhere. The increasing number of public, private, commercial, and consumer grade broadcasts mean that the designated wifi spectrum is growing more crowded. Like lanes on a highway, there are a limited number of wifi channels to choose from. Car drivers try to avoid traffic and choose the least crowded lane on the road. Likewise, you will get the best wifi experience by “driving” in the least congested wifi channel.

icon for Wireless Diagnostics application

Also available by Option-clicking on the WiFi icon in the menu bar and choosing Open Wireless Diagnostics…

Apple computers have a built in Wireless Diagnostics service with a sub program that recommends the best wifi channel. It’s hidden away in the system folder and I have a hard time remembering the exact clicks and keystrokes to find it. So I wrote an AppleScript that runs inside an Automator Service to make the exact window pop up when I need it.

screenshot of Automator workflow

This is how I wrote the script in Automator. Can you make it better?

This is the easiest way to get it in the right place:

  1. Download this ZIP file: Find-Best-Wireless-Channel.workflow.zip
  2. Double-click the ZIP file to unzip it.
  3. While still in the Finder, click Go to Folder… under the Go menubar item. Alternatively, press the key combination ⇧⌘G (Shift-Command-G).
  4. In the little window that drops down, type the following: ~/Library/Services
  5. Hit the (Return) key. The Finder will navigate directly to that folder.
  6. Copy or move the Find-Best-Wireless-Channel.workflow file to that folder.
    screenshot of folder location in Finder window

    This is place the file should be put.

Once you’ve put the workflow file into that folder, look for it under Finder > Services > General.

screenshot of Finder Services menu items

Mine has a key command assigned to it. See the note at the bottom about how to set that up.

When you click on the “Find Best Wireless Channel” service item the workflow will run and a you should be left with a window named “Scan” opened. The wireless networks that your Mac has found will be listed on the right. Look at the panel on the left.

screenshot of Wireless Diagnostics Scan Summary panel

The red circle is provided to direct your eyeballs where to look.

The best wifi channels will be listed at the bottom. Use these numbers to set your router’s wifi channel. Good luck!

Notes

OS Compatibility

This Automator service works on macOS Sierra. Depending on your current OS and any future OS updates, YMMV.

No Library?

If you can’t see your Library folder, follow the directions found here to unhide your Library.

Roll Your Own

For those of you that like to DIY, here’s the raw script.

tell application "Wireless Diagnostics"
	activate
	# opens Scan Window
	tell application "System Events" to keystroke "4" using {command down, option down}
	# brings Assistant Window to the front and closes it
	tell application "System Events" to keystroke "1" using {command down, option down}
	tell application "System Events" to keystroke "w" using {command down}
end tell

Keystroke Combo Power-Ups!

If you want to assign a key command to this workflow service like I did, open up  > System Preferences… > Keyboard > Shortcuts. In the left panel select Services and scroll down to the bottom of the right panel. Next to “Find Best Wireless Channel” click the word “none” and then the “Add Shortcut” button that appears. Press the combination of keys you want to trigger the workflow. Voilà!

screenshot of Keyboard Shortcuts in System Preferences

Assign whatever key combination you like.

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iPad/iPhone Live Video Streaming

Need to stream video over a network using iOS devices? Transmitting video over wifi or Cat5e using an Apple tablet or phone can be really easy. This is how to do it.

A recent gig required live video and audio streamed from one building to a projection screen in another building some distance away. The gig came as a last minute request (the night before a morning event). I had little time to prepare. They were in a bind and didn’t have anyone else they could count on. Though I did not own very much video equipment, I knew I had to help. I had to be creative in order to accomplish the task. Here is what I did.

First, I broke the problem into 2 parts: audio and video. Figuring out an audio solution was easy, since I’m primarily experienced in audio and had all the gear for that portion. So the tough part was figuring out video. Another factor to consider was that the signals needed to be fairly secure (to prevent easy hacking), so wired was preferred over wireless options. My plan was to send audio over balanced audio cables and video over ethernet/Cat5e cable to reassemble on them together on the other end.

Second, I scoped out the location. The buildings were two small structures set on opposite sides of a small parking lot. A quick reading with my super handy laser distance measurer revealed the buildings sat about 100 feet apart. This measurement was helpful for figuring out how much cabling I need to run between the two locations. In addition to the distance between the two, there was also a height factor (the receiving location was on the second floor), plus there were interior distances that needed to be run. Altogether the total distance from the source to the destination required enough cable to reach somewhere in the ballpark of 200 feet.

Third, I needed to inventory my equipment list to figure what I needed to buy, if anything. Luckily, I found a nice iOS app that streams video quite reliably.

Video Signal Flow

This is the basic routing I came up with:

iOS Device with Video Source App > Wifi Router > Ethernet Cable > Computer with Video Destination App > HDMI Cable > Output Device (Display or Projector)

And here are the specific details of my setup:

  1. a newer iOS Device (iPad/iPhone/iPod touch) with good camera (I used an iPad Mini 2.)
  2. a video streaming iOS app (I used AirBeam by Appologics UG with its companion desktop app AirBeam Pro.)
  3. a wifi router (I used an older AirPort Extreme Base Station A1354. For increased security, I also made sure the SSID was not broadcast, the network required a WPA2 password, and the password was fairly long and complicated. Not a perfect solution, but much better than an open wide, password-free network.)
  4. Cat5e cable (I used cable rated for outdoor use since it was kind of rainy and wet outside.)
  5. an Apple computer with ethernet jack (I used an aged Mid-2010 MacBook Pro.)
  6. a video adapter for connection to video cable (I used one of these AmazonBasics Mini DisplayPort (Thunderbolt) to HDMI adapters.)
  7. a video cable (I used an HDMI to HDMI cable.)
  8. an output device (I used a projector.)

Here is a sketch of my set up:

diagram of iOS live video streaming  gear connections

Not shown: MiniDisplay Port to HDMI adapter

I didn’t describe or diagram my audio setup as it was a little more traditional in approach. I may or may not write about that in another article.

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FIX: You are opening the application “Pro Tools” for the first time.

There’s a first time for everything. This is not one of those times.

Blame it on entropy or whatever. Things get messed up. Apple’s OS X is no exception.

In the last few months, I started getting this error a lot:

screen grab of an OS X alert dialog box

You are opening the application ”Pro Tools” for the first time. Are you sure you want to open this application?

Except, it’s not true. I open Pro Tools nearly every day. The alert isn’t very important, but it was beginning to get annoying seeing this pop up every time I wanted to record.

So, a little googling and I found an answer on StackExchange. It involves using the command line on your Mac, which can be a bit scary if you’ve never done that before. But it’s a single command, so you should do just fine. Here’s the quick and dirty summary…

Terminal application icon

This is where the Matrix is on your Mac. There’s no green falling code or woman in the red dress. There may Agent Smiths lurking though.

The Fix

  1. Open the Terminal application (found in /Applications/Utilities/).
  2. Copy the following command (all of it… the whole long line) and paste it after the prompt.
  3. /System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -all local,system,user
  4. Hit the Enter/Return key.
  5. The process will begin. It may take a minute or two to finish. Do not quit the Terminal application while the command is running.
  6. Eventually the process will complete and another prompt will appear. Now you can quit the Terminal app.

This command resets all of the first run warnings. So any application that requires that will be reset. So you should see the alert one more time for each of those applications and then it will go away for good.

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Custom Cell Formats in Numbers Spreadsheets

How to create custom cell formats in Apple Numbers.

graphic of Numbers logo

I really like spreadsheets. Lately, I’ve been building spreadsheets about electronics stuff in Numbers, which is Apple’s version of Excel. I was curious about how to use custom cell formatting to display the correct unit abbreviations on values. Here’s how I did it for Ohms, the SI derived unit for electrical resistance.

  1. Click in the cell you want to format.
  2. Hitting Option (⌥) + Command (⌘) + I opens the Inspector window. It’s also available in the menu bar under View > Show Inspector.
    screen grab of Inspector window in Numbers
  3. Click the Cells tab (it looks like a little 42 in a box).
  4. Under Cell Format heading choose Custom… from the drop down menu.
    screen grab of Ohms listed in Cell Format drop down menu
  5. In the Name field type “Ohms” (without the quotes).
  6. Make sure “Number & Text” is selected in the Type drop down menu.
  7. From the Number & Text Elements field drag the Decimals (.##) element into the field with the existing Integers (#,###) element in it.
  8. Add a space after the Decimals element, then type the symbol for Ohms, which is the omega character (Ω). The keyboard shortcut for this is Option (⌥) + Z.
  9. Click the plus (+) button on the right twice to add two more conditions.
  10. In the first added condition, select “If greater than or equal to …” from the drop down menu.
  11. In the field to the right of that drop down type “1000000” (one million without the quotes).
  12. In the element field below that, make sure there’s an Integers element, a Decimals element, a space, a Scale element set to Millions (M), and finally an omega.
  13. For the second condition you added do the exact same thing as above, but enter “1000” (one thousand without quotes) and set the Scale element to Thousands (K).
  14. If everything looks like the screenshot below, hit OK.

screen grab of Cell Format window

Now when you type a value into that field, it should automatically format into Ω, KΩ, and MΩ. If not, go to step 4 and double check that everything was entered correctly.

Your newly created formatting will be added to the Cell Format drop down. You can now select other cells and apply this custom formatting to them. The custom format will be saved in this Numbers file.

screen grab of Cell Format drop down menu

Try creating custom cell formats for other SI Units too.

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Bluetooth Pairing Unsuccessful

An alternate method that might make your Bluetooth device connect with your iOS device.

January 11th, 2014 | Technology | , , , , , , , | Comments: 5

Can’t get your Apple Bluetooth keyboard to pair with your iPhone, iPad, or iPod touch? I couldn’t either. My A1255 keyboard wouldn’t connect at all. The iPhone would find the keyboard, but wouldn’t update the name of it, nor ever present the four digit code for pairing. I could only get this error:

Bluetooth Pairing Unsuccessful alert screengrab

Pairing Unsuccessful
Make sure “Keyboard” is turned on, in range, and is ready to pair.

I tried a bunch of fixes I read about online and none of these worked in any combination nor configuration:

  1. turning Bluetooth off and on
  2. rebooting the iPhone
  3. holding the power button on the keyboard
  4. deleting other Bluetooth device pairing from the iPhone
  5. clicking ‘Forget This Device’
  6. connecting to another device and then my iPhone
  7. replacing the batteries
  8. holding the V, A, and R keys while powering on the keyboard
  9. turning off Bluetooth on any other nearby devices

It seems Bluetooth under iOS 7 is broken. Lots of people are having issues with Bluetooth on iOS 7 that weren’t there in older iOS versions. Unfortunately, Apple is apparently ignoring this problem.

The Fix

Here’s how I finally connected my keyboard to my iPhone.

  1. Switch off Bluetooth on iOS device under Settings > Bluetooth.
  2. Shut off the keyboard by pressing and holding the power button for 3 seconds.
  3. Switch on Bluetooth on iOS device.
  4. Turn on the keyboard by pressing and holding the power button until it green light blinks.
  5. The keyboard should appear listed under the DEVICES heading in the iPhone Bluetooth settings screen with “Not Paired” in gray next to it. Bluetooth settings screengrab
  6. Now at this point you’re supposed to just tap on the listed device on the iPhone to begin the pairing process, but when I would do that it would time out with the “Pairing Unsuccessful” alert. Here’s the trick: repeatedly tap on the listing (maybe 5-6 times) and hopefully the “Bluetooth Pairing Request” alert will appear with the four digit code you’ll need to enter. Bluetooth Pairing Request alert screengrab
  7. The pairing may fail the first time. Try again.
  8. I also found that subsequent attempts to connect after forgetting the device worked much better after that initial connection.

I hope this fix works for you. Let me know if it does.

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