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Sharp CJ13M10/20KS100

SuntharAbout 4 minCRT RGB mod

Sharp CJ13M10 CRT RGB mod

This tutorial covers the RGB mod for Sharp CJ13M10. These instructions should also work for

  • Sharp CL13M10
  • Sharp 20KS100

This CRT TV is definitely worth RGB modding because it only comes with one composite input in the front and an RF input at the back. RGB modding this CRT is fairly straightforward.

This mod doesn't work on the below Sharp CRTs. The below newer version of the CRTs use IX3354CE, which uses digital RGB. Therefore, they can't be modded.

  • Sharp CN13M10B/CN13M10 (2000 and later)

CRT safety

Caution

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

Plan of attack

READ THIS TO PREPARE

Theory

Sometimes it is nice to know the theory behind the mod. I have put this on a separate page. This shows how the various resistor values are calculated.

READ THE RGB MODDING THEORY

Specs

Sharp CJ13M10

  • Manufactured:
  • NTSC, 60 Hz
  • Chassis:
  • Tube: CPJ370BVBK1S

Sharp

  • Manufactured:
  • NTSC, 60 Hz
  • Chassis:
  • Tube: 37GDA86X

Service manuals

I couldn't find the service manual for this TV.

The below service manual has equivalent circuit.

Schematics

IX2933CE Chroma Chip

img

Mux diagram

If you are building your own circuit, this diagram should help

img

Calculating the RGB external resistor value

Love it when we can put theories to use! Formula from our theory page!

img

RGB external resistor value = 0.7 x (6800 + 75) - (75 x 5) / (5 - 0.7) = (4812 - 375) / 4.3 = 1030 ohm

~ 1 Kohm resistors should do the job.

Performing the mod

Now that you roughly know what needs to be done, prepare for the mod. Place the board on a comfortable place. Make sure you are not putting pressure on the flyback or other components.

STEP 1: Remove the following components

Remove the following components. RGB resistors to the ground. Measure twice and mark before you remove.

  • R803 (1.8 kΩ)
  • R804 (1.8 kΩ)
  • R805 (1.8 kΩ)

Optional

  • Replace 0.1uF, 50V electrolytic capacitors with 0.1uF, 50V ceramic capacitors
  • Add a diode inline for the blanking circuitry and replace the 6.8kΩ resistor with a 4.7kΩ resistor.

STEP 2: Connect RGBs, Blanking and Audio

Close up of RGB and Blanking img

Close up of Sync and Audio img

All wired up! img

Another picture from a different set img

STEP 3: Ceramic inline caps (optional)

I would recommend changing the inline RGB caps to 0.1uF ceramic capacitors. img

STEP 4: Add diode to the blanking

On the CRT chassis change R2027 from 6.8k to 4.7k along with a 1N4148 diode.

This is recommended to reduce interference. See the mux diagram above and the picture circled below.

Diode stripe should be pointing in the correct direction.

img

STEP 5: Build your mux board

Below mod uses the RGB mux board. This is optional, but will make your mod easier and stable. You can also create the circuit presented in the schematics above without the board. Please also checkout the precalculated resistor values.

Buy your RGB mux board

TV ModelCJ13M10
Audio LR (R7, R8)1kΩ
RGB termination (R1, R2, R3)75Ω
RGB inline resistors (R4, R5, R6)1.2kΩ
Diode (R11)1N4148
Blanking Resistor (R9)4.7kΩ
Blanking Ground Resistor (R10) optionalopen
Add diodes to RGB linesNo

img

Buy your RGB mux board

STEP 6: Attach the female SCART connector to TV

img Creating a SCART cutout and mounting it is an art. I have a dedicated section for it.

How to create and mount a SCART female plug?

Route the ribbon cables carefully, not touching the heat sinks or high voltage. img

img

img

Remote Control for this TV

img

Getting into service menu

While pressing the Vol-up and Ch-up buttons at the sametime, plug the AC cord into a wall socket.

Pictures of the mod

Games

NES Adventure Island img

NES Adventure Island Close up img

SNES Contra Alien Wars img

Game menu overlay (mux in action) img

Genesis 2 Sonic The Hedgehog img

XBOX Unleash X menu img

Patterns

Text from FXPAK Pro img

Grid img

SMPTE Color Bars img

Neck board ground wire mod

The ground wire from the tube is soldered to the neck board, which makes it difficult to remove the board entirely from the CRT. While, this may not be necessary for this RGB mod, it definitely makes it easy to connect/disconnect the ground wire attached to the tube. I found the cable and the pin from another CRT that was going to be recycled.

Neck board back img

Neck board pin soldered img

Tube new wire soldered img

Neck board ground attached img

Pictures of the set

Back label img

Swapped tube

Originally this late 90s set came with the following tube: CPJ370BVBK1S

img

However, it can be replaced with the newer tube: 37GDA86X. It works without any issues.

img

Service menu settings

CJ13M10

TV1

NUMSETTINGVALUEFIXED
S01PICTURE60DEFAULT
S02TINT3DDEFAULT
S03COLOR33DEFAULT
S04BRIGHTNESS56DEFAULT
S05SHARPNESS24DEFAULT
S06VERTICAL PHASE06DEFAULT
S07HORIZONTAL PHASE17DEFAULT
S08RF-AGC26DEFAULT
S09VCO12DEFAULT
S10VERTICAL AMP26DEFAULT
S11R CUT-OFF0900
S12G CUT -OFF00DEFAULT
S13B CUT-OFF24DEFAULT
S14G GAIN9FDEFAULT
S15B GAIN84DEFAULT
S16TRAP00DEFAULT
S17BALANCE20DEFAULT
S18C.C.POSITION1CDEFAULT
S19Y-MUTE00DEFAULT

TV2

NUMSETTINGVALUEFIXED
S01PICTURE55DEFAULT
S02TINT3F20
S03COLOR33DEFAULT
S04BRIGHTNESS4B42
S05SHARPNESS24DEFAULT
S06VERTICAL PHASE00DEFAULT
S07HORIZONTAL PHASE1214
S08RF-AGC26DEFAULT
S09VSIZE?26DEFAULT
S10VERTICAL AMP24DEFAULT
S11R CUT-OFF0016
S12G CUT -OFF3316
S13B CUT-OFF5416
S14G GAINA3DEFAULT
S15B GAIN8984
S16TRAP00DEFAULT
S17BALANCE20DEFAULT
S18C.C.POSITION1CDEFAULT
S19Y-MUTE00DEFAULT
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