Toshiba 27A40
Toshiba 27A40 CRT RGB mod
The Toshiba 27A40 is a 27" curved-screen CRT television originally released in 2000.
Features a complete set of connections including Component (YPbPr), S-Video, Composite, and RF.
View full CRT details and more mod examples →
Contributors
Thank you to everyone who contributed to this guide:
- Daniel Labrador — contributor, Pictures
- Sunthar — contributor, RGB mod guide
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: Thailand (2000)
- Format: NTSC
- Chassis: TAC 0015
- Tube: Toshiba A68ADT28X04
- Jungle Chip: Toshiba TA1310AN
- OSD Chip: TMPA8700CPN-1A05
- Screen Size: 27"
- Power: 88 W
- Weight: 68.6 lbs
- Inputs: Composite, S-Video, RF, Component YPbPr
Chassis
RGB mux diagram
Prepare the mux diagram. If you are building your own circuit, this diagram should help.
Performing the mod
Warning
Pictures below show the mux mod method. Better approach is to directly inject R, G, B to pins 3, 4, 5 and blanking to pin 6.
STEP 1: Remove the grounding resistors and capacitors
We are going to remove the three 1kΩ RGB ground resistors.
Remove
- R262 (1kΩ)
- R264 (1kΩ)
- R266 (1kΩ)
STEP 2: Connect RGB and blanking wires
STEP 3: Connect sync, ground, and audio
STEP 4: Build your mux circuit
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.
| On Toshiba CRT Chassis | 27A40 |
|---|---|
| 0.1μF caps replaced | No |
| Add diodes on chassis RGB lines? | No |
| Add blanking diode on chassis | Yes |
| RGB mux board | 27A40 |
|---|---|
| Mux board RGB termination (R1, R2, R3) | 75Ω |
| Mux board RGB input capacitors (R4, R5, R6) | 0.1μF |
| Mux board Audio LR (R7, R8) | 1kΩ |
| Mux board blanking diode (R9) | 1N4148 |
| Mux board blanking ground resistor (R10) | open |
| Mux board blanking resistor (R11) | 1kΩ |
Compatible mux boards:
Pictures
Set
Back open 
Pictures
Reference Photos
