- Joined
- Feb 22, 2008
- Messages
- 8,889
- Reaction score
- 529
In the last few days I found a few TVs with broken necks, So I decided to dissect them and document the results if anyone is interested
CRT is Cathode Ray Tube, AKA: Monitor / TV / Screen / Tube
I firstly was trying to understand how it all works myself, and now I see how amazing it is they ever got these to work
12 Pin, 25", 110 Degree CRT (With a non original neck board on it)

The 3 guns are aimed perfectly through these holes as shown

See the convergence strip held on the Yoke (See pic above - Black Writing)

The funny thing about that little strip, how did it get there? Did they remove the yoke, meaning convergence had to be started again? Maybe it was slipped under, which is why it fell off so easy?? We will never know
So knowing the guns are next to one another may help us understand convergence. Since the beams run almost parallel until they reach the centre of the screen, you can see how a convergence strip (a MU Metal strip) can effect certain colors only, when converging. Also you can see how Green is in the centre and harder to control
There is a lot going on, so I wanted to know what all the pieces were in the neck of the CRT. This pic shows some of the visible levels as viewed from inside the tube.

This pic below shows the (insert correct name of the part here) which would press against the glass (On the opposite side as the adode) and cause the HV potential to be felt here and at the metal it's connected to.

Here are the locations of everything (Heater resistance of this one is 2.2 ohms

8 Pin, 15", 90 Degree CRT
Here is the neck broken off

Here is the glass removed from the neck so I could use an Ohmmeter to bell out the pins

The heater is just a strip of copper (Nichrome Wire?) You can see why a CRT is toast if the heater burns out
CRT is Cathode Ray Tube, AKA: Monitor / TV / Screen / Tube
I firstly was trying to understand how it all works myself, and now I see how amazing it is they ever got these to work
- So, I got an 8 Pin from a 15" TV. Someone had stolen the yoke for scrap metal, so I kicked the neck off the screen and took it
- Then I found a 110 degree 25" CRT which was cleanly broken off at the neck, with the yoke intact
- I would like to do this with a B&W one day, if I ever see one getting trashed
12 Pin, 25", 110 Degree CRT (With a non original neck board on it)

The 3 guns are aimed perfectly through these holes as shown

See the convergence strip held on the Yoke (See pic above - Black Writing)

The funny thing about that little strip, how did it get there? Did they remove the yoke, meaning convergence had to be started again? Maybe it was slipped under, which is why it fell off so easy?? We will never know
So knowing the guns are next to one another may help us understand convergence. Since the beams run almost parallel until they reach the centre of the screen, you can see how a convergence strip (a MU Metal strip) can effect certain colors only, when converging. Also you can see how Green is in the centre and harder to control
There is a lot going on, so I wanted to know what all the pieces were in the neck of the CRT. This pic shows some of the visible levels as viewed from inside the tube.

This pic below shows the (insert correct name of the part here) which would press against the glass (On the opposite side as the adode) and cause the HV potential to be felt here and at the metal it's connected to.

Here are the locations of everything (Heater resistance of this one is 2.2 ohms

8 Pin, 15", 90 Degree CRT
Here is the neck broken off

Here is the glass removed from the neck so I could use an Ohmmeter to bell out the pins

The heater is just a strip of copper (Nichrome Wire?) You can see why a CRT is toast if the heater burns out
Last edited:













