Samsung TXD1973
Samsung TXD1973 CRT RGB mod
The Samsung TXD1973 is a 19" CRT television popular for its ability to be easily modified to support RGB/SCART input.
Tube in this set can be used to swap a K4600 tube.
View full CRT details and more mod examples →
Contributors
Thank you to everyone who contributed to this guide:
- Sunthar — contributor, RGB mod
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
Manuals and Datasheets
Specs
- Manufactured: Mexico (1997)
- Chassis: K1
- Tube: Samsung A48KRD82X
- Jungle Chip: Samsung KA2163
- OSD Chip: Zilog SZM-284EV
- Screen Size: 19"
- Inputs: RF, Composite
Prototyping the mod
Since this is the first time I'm modding a CRT from Samsung, I wanted to prototype the mod first. I reviewed the schematics and came up with the below plan.
The main board is fairly compact. The main board also comes off the CRT completely, if all the wires are carefully disconnected. This makes it easier to perform the mod. Please make sure to remember or take photos as you disassemble, so that you can reassemble the way it was prior to disassembly.
RGB mux diagram
Prepare the mux diagram. If you are building your own circuit, this diagram should help.
Performing the mod
This CRT was fairly straightforward to mod. You can perform the mod on the board itself and don't need a MUX board.
Using the stock SCART port
This CRT comes with a stock AV port that has a SCART cutout. I wanted to utilize this to give this CRT a clean look. Here is how it looks when finished.
You will soon realize this is not as easy as it looks. There isn't that much space on the board to accomodate a SCART plug and the necessary wiring.
How was this achieved?
Remove the existing A/V connector.
Move some of the components to the bottom of the board to make some space.
Create a flexible pcb that grouned the relevant pins together and allowed for routing of the wires. Flexible pcb was used, because there is not much clearance and you want this to be flexible. I'll let the pictures below explain the process.
Check the placement of the flex pcb 
Make your own flex ribbon board at OSHPark or buy it here
Attach all the necessary wires 
Flush cut the SCART pins and solder to the flexible pcb. 
Insulate the SCART adapter with some electrical tape 
Insulate the main chassis 
Insulate more 
SCART soldered 
SCART side view 
Removed R204, R205, R206. Used the existing vias to connect R, G, B, blanking and ground.
- R, G, B (red, green, blue wires)
- Fast Blanking (brown wire)
- Ground (black and purple wire)
- Ground (leave the organge wire disconnected)
- CSYNC - directly connect the CSYNC pin to the board and solder it.
RGB wires needs a triangle formed between 75 ohms and 1.2 kohms. 75 ohms goes to the grounding side. 1.2kohms faces the 0.1uF capacitors. 
Blanking wire (brown) needs a didoe inline. Replace the existing blanking inline resistor with another diode and put a 6.8 kohm resistor after the diode. 
Bypass the CCD to ensure the video is not dark 
Audio wiring (grey, white). Put two 1 kohm resistors for both left and right wires and connect them both to the board 
Ground wiring (black, purple). Twist them together and connect them to the below location.
Connect CSYNC to this location 
Warning
Use heat shrink tubes to prevent shorting. 
All wired up! 
How the back of the TV looks after buttoning everything up. 
Tips
Connector will be a bit wobbly. However, once the back cover is put back in place and closed up with screws, connector should stay strong. Please be mindful not to push the connector in too tightly and break the connector. Understand the limitations of this mod and possibly use an extension not to damage the SCART connector. SCART closeup. Back cover holds connector in place. 
Adjustments, Games and Patterns
Colors don't really pop on this TV for some reason. But, it has a nice overall look that will give an awesome nostalgic experience. Modding this TV is really straightforward. Image was a bit washed out, right after injecting the RGB signal without touching anything on the CRT.
Let's see what options we have to make this look better.
Adjusting the flyback screen brightness
After decreasing the screen brightness on flyback, colors seemed to be much better. OSD menu overlay was also visible. 
Service Menu
While in Standby mode, using the remote MUTE > 1 > 8 > 2 > POWER should bring you to the service menu.
Default settings for this CRT 
Adjusted values 
HS - Horizontal Shift was adjusted to center the RGB image. RC - Red Cutoff and GC - Green Cutoff was adjusted to 0 and 21 respectively to reduce the redness and balance the colors. YMMV.
This 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 mux calculator to play with your own values.
| Component | Value |
|---|---|
| RGB/OSD inline resistor (chassis) | 7.5kΩ |
| Removed RGB/OSD resistor (chassis) | 1.2kΩ |
| RGB inline diode method (chassis) | No |
| RGB termination (R1, R2, R3) | 75Ω |
| RGB inline (R4, R5, R6) | 1.2kΩ |
| Audio LR (R7, R8) | 1kΩ |
| Diode (R9) | 1N4148 |
| Blanking Ground Resistor (R10) | open |
| Blanking Resistor (R11) | 1kΩ |
Compatible mux boards:
If you want a more stable finish, and want to retain the AV input at the back, and willing to cut a SCART port, then you can use a 1.4B or 1.4C board kit for the modification, depending on your preference.
If you are adding diodes on the R, G, B lines (optional), then you would use 1500k on R4, R5, R6 instead of 1200k.
Pictures
Reference Photos
See more photos and contributions →