Sony KV (ANU-2) 20EXR20
Sony ANU-2 chassis RGB mod
Bring your Sony CRT to life with vibrant RGB colors!
This RGB mod applies to the following models. Other ANU-2 chassis can also utilize the same mod.
- KV-20EXR10
- KV-20EXR15
- KV-20EXR20
- KV-27EXR10
- KV-27EXR15*
- KV-27EXR20
- KV-27EXR25*
*The P-Board for Picture-in-Picture functionality must be removed in these models.
Sony KV-20EXR20
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.
Plan of attack
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.
Service manuals
Specs
Sony KV-20EXR20
- Manufactured: February 1992, Mexico
- NTSC, 60 Hz
- Chassis: ANU-2
- Tube: Sony Trinitron A51JUH50X
- Jungle Chip: CXA1313AS
- OSD Chip: M37100M8-115SP
Schematics
SCART schematics
BNC schematics
The RGB mod
Please note below mod uses an external switch for the 5V.
STEP 1: Add resistors
Locate the empty resistor spots labeled R319, R320, R321, and R322 near IC301, add 100 ohm resistors into them. Add a 150 ohm grounding resistor between R319 and one of the ground pads on the unpopulated A-31 header, this will act as a voltage divider for our blanking circuit.
Add 100Ω and 150Ω resistors
100Ω resistors
150Ω resistor
STEP 2: Add a header
Populate the A-31 header with a 5-pin male DuPont header connector in the pins labeled "B IN", "G IN", "R IN", "E", and "YS". The first four pins mentioned will be for ground and RGB, and the "YS" pin will be for blanking.
STEP 3: Blanking wiring
Run wires from the output of the 5V regulator (TP96A near the tuner would be the perfect place) and the "YS" pin of A-31 to your blanking switch on the middle and right pins repectively.
Alternatively, you can also use the 5V from pin 16 of the SCART connector for blanking.
STEP 4:
Wire your RGB connectors to a 4-pin female DuPont connector for the A-31 header with 0.1 uF ceramic capacitors inline and 75 ohm resistors terminating the RGB connectors to ground.
STEP 5: Optional if not using SCART
Run wires from the S-Video Luma pin, both Audio signal pins, and the ground of the VIDEO 1 jacks (labeled "J1901") on the U2 board to the SCART connector. Refer to the diagram for the pin arrangement. Bear in mind that there is a metal shield that covers this board upon reassembly, so take care when routing your wires.
To enable the S-Video input as a Sync source for your SCART connector, you must trigger the sensing circuit. You can do this either by running a jumper wire from the Sense (upper center pin) and Ground (lower center pin) of the S-Video connector, or by wiring those pins to the second pole of a DPDT switch.
STEP 6:
Go into the service menu and adjust the horizontal position (labeled "HPOS" in the service menu) until it looks properly centered. If you're inputting sync into the S-Video input, you should only have to adjust it by about 2 or 3 subtracted from the original value.
If you're using RCA or BNC jacks for RGB, sync should be input to the S-Video input via an adapter. This will reduce the horizontal shift on your RGB image.
TV Model | KV-20EXR20 |
---|---|
Audio LR (R7, R8) | 1kΩ |
RGB termination (R1, R2, R3) | 75Ω |
RGB inline caps (R4, R5, R6) | 0.1uF |
Diode (R9) | Shorted |
Blanking Resistor (R11) | 4.7kΩ |