Converting Monitors from Composite to RGB


Well-known member
WARNING:‎ If you are not aware of the deadly component(s) in a CRT's and other electronics, such as capacitors, tube charge, etc, you should learn about this first or don't attempt to tamper with the components because it could cause serious injury or DEATH. I have seen this done in a repair facility and if you have not seen or heard the discharge pop, you should because you will respect it for sure. See important comments below about another possible serious shock hazard. There may be more safety info in the youtube video's comments.

"Something to be aware of with even older TVs, is that they may have a hot/live chassis that isn't isolated from the mains supply. Those will require an isolation transformer, in order to safely modify for RGB. Can see that 8-Bit's (video's producer) Samsung has a large mains transformer in it, so that's definitely isolated.‎"
"The whole "hot chassis" thing is very common on TVs in 110V-120V land.

It can be super dangerous (lethal) if somebody tried to mod one of those TVs with external inputs that bypass the isolation.

You can often (but not always) tell if a TV has a hot chassis if it has an insulation block between the RF tuner and the antenna socket.

People have been recently injured attempting mods like this, so it's worth mentioning every time.

It should go without saying that the CRT and larger caps should be safely discharged before working on a TV or monitor, too.

‎. . . at ‎around 3:53‎ in the video, you can see near the bottom of the board where it has the "HOT" and "COLD" sides clearly marked on the PCB silkscreen.

As Michael pointed out, this specific TV has a switched-mode power supply, so it has the proper isolation between the mains side and low(er)-voltage side.

The "hot chassis" style TVs don't have ANY of that separation / isolation at all, which means that the entire board is essentially floating at MAINS potential!

That could be 170 Volts or more of rectified DC. If the insulator on the tuner is bypassed in any way, like adding external wires for an RGB mod, it can create a serious electrocution risk.

This isn't just me being overly-dramatic, btw, it's a real issue atm, as it never seems to get mentioned in the modding videos.‎"