Pranks: CRT Monitor

I am a queer, transgender, nonbinary, and mixed-race picture book writer/illustrator. As a young ...

My brother works for a local tech company. Whenever a new hire comes on, someone is responsible for setting up their office and showing them around during the first few days. The people there have a pretty sweet set up with large thin dual monitors. But, we decided to have a little fun with the set up and replace the new hire's awesome monitors with an old-fashioned CRT.

We did this a while back, so unfortunately I don't have quite as much documentation as I'd like.


  • CRT monitor
  • Computer that can accept DVI input or a DVI to VGA/HDMI adaptor.
  • Hiding place for actual monitors.

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Step 1: Gathering Materials

  • I was able to dig an old CRT out of storage, but you could probably find one on Freecycle, a local tech swap/recycling place, university computer lab clean outs, or your grandmother's basement.
  • Newer monitors and computers have different ports than many older monitors. This particular monitor was DVI only, but the computer it was hooked up to did not have a DVI port.

If you have trouble finding either of those for free, there's always eBay and Craigslist. I had a number of CRT monitors and converters come up on eBay for around $10 for a monitor or $1 for a converter. (Search for "CRT monitor" and "DVI to VGA", sort by price+shipping: lowest first.)

Step 2: The Set Up

We wanted to make sure the actual monitors were still in the new hire's cube, but well hidden. The new hire's office had a larger desk, a small table/desk, and a rolling filing cabinet. This set up provided the perfect hiding system. It's a little bit difficult to see in the photos, but the smaller desk/table is pushed all the way against the wall. The filing cabinet is not attached. It is on wheels and easily rolls out. By pushing the side of the larger desk against the smaller desk, there was a nice cubby space to hide the actual monitors. We used the rolling filing cabinet to block access to the real monitors to make it a little bit more difficult to find, but still easy to access.

We set this up on the weekend, during off hours to make sure we weren't caught.

See illustration!

Step 3: The Story

On the new guy's first day my brother showed him his new office. You could choose to either ignore the fact that there's a CRT or say something along the lines of: "Yeah I don't know what's up with that monitor. But, don't worry, I already sent in a request to IT. I'm sure your new one will arrive soon."

Hopefully your friends are better with pranks than my brothers' because they were a little heavy handed and gave away the location by lunch time.

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    6 Discussions


    2 years ago

    now hook up a raspberry pi loaded with a DOS emulator or similar


    3 years ago

    What's wrong with the CRT monitors? Is it because they have infinite contrast ratio that only OLED displays can get close to? I have several LCD monitors/TVs at home and I hate to even look at them. There is no single angle in front of them that will provide equal lighting all over the screen. Only my two plasma TVs can get that but then again, they are history as the CRTs. Why good things have to go away and make place to new cheap crap we buy now? It's a shame.

    2 replies

    Reply 3 years ago

    Let me tell you the things that are wrong with CRTs. The first is that they cost more in electric than LCDs, and two, if you take a CRT apart to try to fix it, if you touch the wrong thing, it will kill you. Even if you have it unplugged, CRTs use capacitors to turn on quicker. So if you touch it, you will have all the power it takes to turn the CRT on going through your system.


    Reply 3 years ago

    " they cost more in electric than LCDs "
    - this is true for the same size they do need more power to run
    " it will kill you. Even if you have it unplugged "
    - The discussion was about using an CTR TV and not about fixing them. If you don't know what you are doing you are not supposed to open any equipment. I have been fixing CRT TV sets all my life and I am still alive. The Fly back transformer creates high voltage which is multiplied by a cascade of diodes and capacitors to the required anode voltage of about 25 kV but this circuit can provide only 1 mA current. This voltage goes down to zero in a few seconds after shutting down the TV. There are pretty good chances to be killed by working on an LCD TV too if you don't know what you are doing since the power line 120 VAC goes into this sets too and it will provide enough power to kill you if you don't take precaution measures (working in a dry environment and not touching live wires).
    To get killed by electricity, the body needs to receive about 65 mA to get fatal burns. The Ohms Law will tell you what voltage is required to cause such current through your body depending on the resistance of the closed circuit (dry skin has higher resistance) etc.
    " CRTs use capacitors to turn on quicker "
    - Totally wrong, HV capacitors are used for multiplying the voltage in the cascade and not to turn quicker, and they are empty just a few seconds after shutting the set down. Low voltage capacitors (250 V) are used in both CRT and LCD TVs and are holding the electricity equally for no more than 10 seconds.
    The next time you are trying to scare people you need to check the facts. Only trained and skilled technicians need to open any TV and measuring is done by AVO meters not by touching wires with fingers. So much about the CRTs.


    4 years ago

    Good prank. I would rather find a snake in my office than one of those old monitors !


    4 years ago on Introduction

    I found this quite funny! This would be epic for the IT guy pull this prank on the whole office!