# Tube compatibility and swapping

# CRT safety

DANGER

You can die doing this! So read carefully! CRT TV is not a toy. Do not open a CRT TV. If you don't have any prior knowledge about handling high voltage devices, this guide is not for you. CRT TV contains high enough voltage (20,000+ V) and current to be deadly, even when it is turned off.

READ THIS BEFORE CONTINUING

# Sharp/Orion tube swap

Lessons learned:

  • There is no easy cure for horizontal size adjustments on these small CRTs
  • 13" tubes were compatible, even though they had completely different model #'s
  • Keep the yoke, magnetic strips etc. with the respective tubes. Don't swap the yokes
  • If you follow this tutorial, you will learn there is no need to disassemble the yoke or convergence rings. If you do plan to remove them, please make sure to mark the alignment of convergence rings (using whiteout) prior to disassembly.
  • Take photos of your connector wiring before making changes to them
  • Learn how to get into the service menu

# Swapping Sharp 37GDA86X with Orion 34AGT13X98(L)

13" Sharp CN13M10 CRT with 37GDA86X tube had some visible burns from CP24 news channel (popular in Toronto). However, this was a great CRT to RGB mod and was a good candidate to do a tube swapping experiment. I had a spare 13” Toshiba 13A23 CRT with broken shell that had an Orion A34AGT13X98(L) tube. I looked at the below items to see if the tubes were compatible.

  • Resistance/Impedance of the yoke
  • Shape and size of the tube
  • Socket compatibility
  • Yoke connector/plug that goes on the board
  • Degauss coil compatibility

img

  1. I measured the yoke vertical and horizontal resistance using a standard multimeter. Gave few minutes for the reading to settle. Unfortunately, I didn't have an impedance meter.
  • Toshiba 13A23, 34AGT13X98(L)) (Horiz: 6 ohm, Vert: 15 ohm)
  • Sharp CJ13M10, 37GDA86X (Horiz: 6 ohm, Vert: 17 ohm)

Resistances were close enough.

  1. Shape and size of the tube were compatible. It perfectly fit in each other chassis

  2. Sockets were compatible, though I didn't check to see the heater voltage or if the pins were 1:1 compatible

  3. Yoke was visually different with different connectors and pinout. There were 4 wires. Wires were compatible though some wires had different colors (i.e. Green/Brown wires were compatible).

  4. Degauss coils were slightly different, though the connectors were compatible

# Experiment 1

# Swapping the tubes.

Since most of the items above checked off, I decided to swap the tubes with their respective yokes and hope for the best.

I first wanted to put the bad Sharp tube with the spare Toshiba board and see if they were compatible. This way if anything went wrong, either the bad tube will be damaged or the spare board will be damaged. I was ok with both outcomes, but was not ok with burning down my house. Therefore, prepared for the worst case outcome by doing this experiment in a safe place with easier/quicker access to shut down the power.

I was able to move the pins in the yoke connector from the Sharp CRT to match the Toshiba board.

Voila..! it worked on the first try. Colors were a bit dull - probably because the tube was a bit worn and flyback needed adjustement. Image was shrunk a bit vertically. But, it looked awesome for the very first try. The burn is mild and noticable in white screen, but for some reason it is not visible in the below picture.

img

# Experiment #2

# Swap the yokes.

With this experiment I swapped the yokes. It was a bit of a pain, but I managed to loosen up both the deflection rings and yoke and swap the yokes and rings.

This way, my thinking was I didn't have to rewire the connectors. However, there was a slight problem.

  • Sharp tube with Toshiba yoke and Toshiba board was slightly shrunk horizontally and had several convergence issues img

  • Toshiba/Orion tube with Sharp yoke and Sharp board was slightly expanded horizontally and had several convergence issues img

img

Since I wanted to save the Sharp CRT, I focused on it with the Orion tube and Sharp board. I was able to get the convergence to a pretty good state, but it was not perfect. For the horizontal size issue, there was no easy cure to shrink the image horizontally.

While the results were ok, it was far from acceptable.

# Experiment #3

Keep the yokes the same, but rewire to match the connector.

I wanted the geometry and convergence to be really good. I decided to keep the tubes with their respective yokes. However, this meant I had to also rewire the connectors.

I soldered the yoke wires and the pins such that it matched the board. While it was a bit of a pain, it wasn't too bad at all.

Powered on the CRT (once again taking the necessary precautions to ensure I didn't burn down my house). Horizontal size matched perfectly. I had to make minor tweaks on the Sharp CRT service menu to adjust the veritcal size, position and minor color adjustments. Results were really great for composite input! Both CRTs were saved in this experiment, including my house.

Sharp monoscope pattern with Orion tube img

Sharp grid pattern with Orion tube img

Toshiba grid pattern with Sharp tube img

Toshiba Mega Man X with Sharp tube img

Next is to RGB mod this CRT and tweak it further.

# 13" tubes

A34JXV70X26

  • Memorex MT1136 (A34JXV70X26 - Orion)
  • Toshiba MD13Q11 (A34JXV70X73N45)
  • Durabrand DCT1303R (A34JXV70X)
  • Durabrand DBTV1300 (A34JXV70X)

A34JFQ90X

  • JVC C-13810 (Toshiba A34JFQ90X)
  • Memorex MT1130C (A34JFQ90X)
  • Sharp 13N-M100 (A34JFQ90X)

A34LRQ90X

  • Sharp 13N-M100
  • Durabrand DCT1303R (A34LRQ90X(VW))

CPJ370BVBK1S

  • Sharp 13N-M100

37GDA86X (swappable with A34AGT13X98(L))

  • RCA/GE E13200 (Chassis TX825TC 370GDA86X, Horiz: 3.8 ohm, Vert: 14.4 ohm)
  • Sharp 37GDA86X, Horiz: 6 ohm, Vert: 17 ohm)

A34AGT13X98(L)

  • Toshiba MD13P1
  • Toshiba MV13DN2C (VCR TV - Horiz: 6.0ohm, Vert: 15.2 ohm)
  • Toshiba 13A21C (Horiz: 6.0 ohm, Vert: 15.2 ohm)

37SX110Y22-DC05

  • Batman 13" CRT

# 20" tubes

A51LYZ095X - Flat tube

  • Toshiba 24AF45

# 27" tubes

Swapping tubes of Toshiba 27AF43/27AFX54 (opens new window)