I love the design of these old things. But it's heavy, only in black and white and connecting anything to it require a lot of adapters and it's not working very well at the end.

So here we go, I decided to swap the CRT for a more modern LCD screen with a Raspberry Pi running Retropie. I also needed to have sound so I added a 12v amp with 2 speakers and I wanted it to be portable, so I used a power bank.

It's a bit of a shame to remove the CRT as it's a big part of the coolness of the design on these TV, but with a bit of work I though I could make it quite good looking too.

Supplies

An old TV

LCD screen that fit the old CRT size (12'' in my case) like this

12v amplifier board like this

2 speakers drivers like this

12v Power bank like this

2 switches like this and this

raspberry pi 4 here

usb hub like this

4 usb extensions like this

micro SD extension cable like this

Step 1: Disassembly and Make the New Screen Fitting

One of the big challenge was to replace the CRT with an LCD and make it good looking. After a lot of research online to get a LCD with the right size, I finally found one on ebay from an old cash registering machine (and as a bonus, it's tactile).

First, I disassembled the TV.

/!\ Make sure the CRT is discharged before touching it /!\

I took all the components out of the TV including the CRT, removed some plastic with a Dremel all around the original shape of the CRT and I created a bezel for the LCD screen out of a thin MDF sheet.

Once I was happy with the screen face I made, I glued it in place and filled all the empty spaces with body filler to make a transition between the curved CRT molding and my homemade LCD bezel.

After a lot of sanding, it came out quite ok.

Finally, I applied a few coat of primer and a couple of coat of matte black paint to match the original paint of the TV.

Step 2: The Electronics

I hot glued the screen in place, then I managed to install the amp and make the volume knob fit the original knob of the TV. I was quite lucky on this one as it fit perfectly.

I also installed the 2 switches where the frequencies knobs were originally. The first top push button is for shutting down the pi properly (connected to the GPIO and running a script) and the second one is the main power switch with 3 positions.

I wanted the TV to be portable so I used a power bank that deliver 12v DC jack and 5v USB.

I had several problems to figure out about the power.

First, my power bank deliver 12v 2A max and the charger that comes with it is only 12v 1A. The input and output are on the same DC jack so it comes with a split cable to charge and deliver power at the same time.

Secondly, the power bank needs to be turned on to charge, if it's off it's just bypassed so the wall charger is providing power to whatever is connected to the power bank. In my case, if I turned off the power bank while the charger was plugged in, the pi, screen and amp would not turn off but be powered by the wall charger (and of course 1A is no enough for powering all these devices at the same time). So it was not working for me.

To correct that I used a 3 position 3P3T switch witch control the power bank and open or close the circuit at 2 different places, one between the charger and the power bank and one between the power bank and the devices. So the switch controls 3 things :

turn on or off the power bank (just connected to the original power bank toggle switch)
open or close the circuit at the wall charger
open or close the circuit between the power bank and the devices

This allowed me to have an ''Off'' state where everything is turned off even if the wall charger is plugged in (= no charging even if the wall charger is plugged in) ;

An ''On'' state where everything is turned on, and the power bank can be charged while using it ;

And finally a ''charge only" state witch turn on only the power bank and the wall charger input so I can charge the power bank with the devices shut down.

I don't know if it's clear and I'm sure there is a lot of more clever ways to solve these issues but, that's how I did.

After that I just had to add some little more features : I plugged a USB hub on the USB out of the power bank to have 2 female USB at the back of the TV to charge the games controllers (I also used this hub to power the 5v LED of the front top push button) and I used a micro SD card extension cable I had laying around to have access to the Pi SD card at the back of the TV.

I also added 2 USB on the front side of the TV connected to the Pi.

Step 3: Game Controller Storage and Other Little Things

Finally, I've cut the back of the TV where the safety sticker is to make a small storage compartment witch can store 2 wireless games controllers, their USB cables for charging and the DC charger for the TV.

I've simply used some thin MDF painted in black, some small hinges and a knob from the TV as a small handle.

Originally, there was only one speaker on the face of the TV so I added another one on the side to have stereo, I drilled a lot of holes to make a sort of grill for it.

On the original TV there was an audio jack in the front, I removed it and put the LED of the LCD instead.

Then I made a mount for the 2 USB and micro SD at the back of the TV. I salvaged a broken USB SD card reader and use its plastic shell combined with MDF and epoxy glue to make it clean.

I also wanted to have a battery level indicator, so instead of de-soldering the LEDs of the power bank (they are so tiny, this way beyond my soldering capacities), I glued optic fiber on each LED to root the light on the side of the TV. It's not perfect, but it's working.