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Poor Man’s Digital Signage

Poor Man’s Digital Signage

Here is a cheap solution for digital signage, which I have set up in the foyer of my church.

The concept is to use a WordPress site to deliver various pages and posts to a Raspberry Pi running minimalkioskOS, which displays the web sites on a monitor. Then you can edit the pages in WordPress, and the new and changed content displays on the monitor.


First, Get yourself a Raspberry Pi 3 B+. Something like this Cana Kit for $50 USD should work.

Install minimalkioskOS on your Pi. This solution has been tested and used with version 0.4.2

In the meantime, get yourself a WordPress website, which might be free, or cost you a few bucks. I’m frugal, and use NameCheap for play-around sites.

Set up your WordPress website, the install the free Redirection plugin.

Now create a few pages or posts that you want to display on your digital signage. For example:

  • A page to shop Announcements
  • A post to display Special Events

On your WordPress site, make some more posts or pages with only a title (no content needed), and call them something like:

  • Sign_01
  • Sign_02
  • Sign_03

Now use the redirection plugin to redirect your WordPress pages or posts from the static “sign” urls, to more dynamic content.. Something like this:

  • Sign_01 -> An Announcements page in your WordPress
  • Sign_02 -> Special Events – could be a post in your WordPress
  • Sign_03 -> http://weather.com

Finally, return to minimalkioskOS on your Raspberry Pi, set it up and have the sign cycle through the websites Sign_01, Sign_02 and Sign_03. It will display those websites, which are actually redirected to websites with content of your choice (Announcements, events, other websites etc). This is all handled in the boot/urls.txt file in minimalkioskOS. Instructions below.

You are good to go! Now all your signage editing and updating can be done in WordPress. You can edit the pages that the Sign_xx pages/posts redirect to, or you can redirect them to completely different urls.

You can keep the sign up-to-date by editing the redirection and redirected urls. You don’t need to ssh in to minimalkioskOS and change the sign urls.

I realize these instructions are ridiculously obtuse. I will try to improve them eventually.


Here are some instructions specifically for what you need to do on the Pi:

MinimalkioskOS Instructions.

Install on Pi. [use Etcher to flash a microSD card for your Pi]
Boot up Pi with keyboard attached physically.

Ctrl-Alt-F1 [to get to terminal]

[username:password = pi:raspberry]

cd / [to go back to root]
cd boot [to go in to boot folder]
ls [just to list the folder contents, to be sure]
sudo rm autosecure [removes the random password creator for pi user]
passwd [to change the pi password. Sometimes seems to take multiple tries to stick]

sudo touch ssh [makes the ssh file, so now you can use putty to ssh in to edit these files]
sudo nano urls.txt [add your urls here. Ctrl-x to save and exit]

example:
https://cnn.com 10 [watch cnn.com for 10 seconds]
https://alanrjacobs.com 25 [watch alanrjacobs.com for 25 seconds. time you’ll never get back]

sudo nano minimalkioskos-wpa-supplicant.txt [to set up your wifi, if using wifi. edit this file according to the instructions in the file, to attach to your wifi. Ctrl-x to exit and save] Here is a sample network:
# WPA/WPA2 secured
network={
ssid=”UUCL”
psk=”42B3045119″
}

More than one SSID can be added.

Then you should be good to go. Restart your Pi with the “sudo reboot” command, then use a tool such as Fing on your phone to identify the Pi IP address, then use Putty to ssh in and edit the files in the boot folder as needed.

For my display to work, these are the uncommented lines in config.txt:
disable_overscan=1
config_hdmi_boost=4
See this for more: https://www.raspberrypi.org/documentation/configuration/config-txt/video.md


Here are some other useful linux commands:

  • ifconfig [shows the IP configuration]
  • sudo shutdown now [shuts down immediately]
  • sudo shutdown -r now [restarts immediately]
  • cd .. [goes back one folder]

And remember that Linux is totally case sensitive for all commands and file and folder names.

Homeowner Wiring: Should You Do It?

Homeowner Wiring: Should You Do It?

The other day I learned that if you do electrical wiring, you are responsible and liable for that installation as long as it exists.

Yikes! I guess this should give pause to someone like me who fancies himself to be a handyman, and is happy to do a small DIY project like replacing a receptacle with a GFCI receptacle. Or like the homeowner before me who added a shop light.

I always assumed selling the house relieved my liability! But it’s not. You are on the hook FOREVER!

Evidently if there is a fire, the investigators get up close and personal with stuff like those markings on the wire, and figure out who is responsible!

You can read more scary stuff here.

USPS Security: Change Address

USPS Security: Change Address

When you move, it’s easy to log in to USPS and put in your forwarding address. All you need is to verify your identity with a direct card. This seems so easy for a bad guy to do, and get your mail delivered to a new address.

It’s even possible for a business…

If a thief chose the right week, and was able to set everything up and then get all your mail, they might have time to get away and cover their tracks before you even notice.

I like this convenience and have used it three times during the past year, for both business and personal use.

But it sure seems like a risky thing for the USPS to allow us to do.

USPS Security: Informed Delivery

USPS Security: Informed Delivery

The United States Postal Service has some convenience features which may or may not be secure. I have my doubts.

The first feature is Informed Delivery. You can sign up for free, and then every day you receive an email that has scans of the envelopes you will receive that day. It’s a nice feature when you are eagerly awaiting a certain letter, like an automobile registration or a license.

However, it is relatively easy to sign up and have your identity verified. It occurred to me that someone could impersonate you, and sign up. The could watch the daily emails, and if you have a rural free delivery mailbox, they could swoop in and steal anything that appeared interesting.

I believe the identity verification required a credit card, but the bad guys would find that relatively simple to circumvent.

On top of everything else, the USPS in monetizing this. Informed delivery has crazy high open rates for that email, and gives a traditional mail marketer a lot more information about you, and new tools to get you interested in their products. Read about it here.

This is from the USPS PowerPoint marketing Informed delivery to marketers

Whatever, my recommendation is you sign up for informed delivery before someone does it for you.

Show me that redaction!

Show me that redaction!

This is a cautionary tale! Paul Manafort’s attorneys filed a document that was improperly redacted. You can open the actual document (link below), copy the redacted lines and paste them in to a Word document to reveal the text underneath.

The black highlighter tool is not effective for redaction. Use the actual redact tool.

https://assets.documentcloud.org/documents/5677512/Manafort-20190108-Dc.pdf

As bad as this is for the lawyers, me thinks it’s even worse for Manafort!