Toshiba CF27F50
Toshiba CF27F50 CRT RGB mod
The Toshiba CF27F50 is a 27" consumer CRT known for its high-quality picture tube and suitability for RGB modification.
View full CRT details and more mod examples →
This tutorial should also work for
- Toshiba CF27F50
- Toshiba CL29F50
Table of Contents
Contributors
Thank you to everyone who contributed to this guide:
- Sunthar — author, RGB mod noise issue discussion (Reddit)
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
- Year: 1996
- Format: NTSC
- Chassis: TAC 9618
- Tube: Toshiba A48KZL70X
- Jungle Chip: Toshiba TA1223AN
- OSD Chip: Toshiba TMP87CM34BN
- Screen Size: 27"
- Weight: 22 lbs
- Inputs: Composite, RF
Schematics
RGB mux diagram
Prepare the mux diagram. If you are building your own circuit, this diagram should help.
Performing the mod
Detailed mod instructions to be added.
Remove resistors RR90, RR91 and RR92. Inject R, G, B signals respectively. Don't remove grounding resistor on the blanking line. See picture above to see where to inject the blanking signal.
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 | CF27F50 |
|---|---|
| CRT RGB inline resistor | 4.7kΩ |
| CRT RGB ground resistors removed | 1.2kΩ |
| 0.1μF caps replaced | Yes |
| Add diodes on chassis RGB lines? | Yes |
| Add blanking diode on chassis | Yes |
| Replace blanking resistor on chassis | No |
| RGB mux board | CF27F50 |
|---|---|
| Mux board RGB termination (R1, R2, R3) | 180Ω |
| Mux board RGB inline resistors (R4, R5, R6) | 1kΩ |
| 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) | 4.7kΩ |
Compatible mux boards:
Pictures
Reference Photos
