Skip to main content

Sanyo AVM-2507/2508

About 2 minCRT RGB mod

Sanyo AVM-2507 CRT RGB mod

Coming soon

  • Sanyo AVM-2507
  • Sanyo AVM-2508
  • Sanyo DS25730

CRT safety


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



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.



Sanyo AVM-2507

  • Chroma: LA76070N (IC101)
  • OSD: M37272M8-100SP (IC801)

Service manuals

Sanyo AVM-2507 Service Manual

Calculating the RGB external resistor value

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

We find out using ohms law, this CRT is using 0.5Vp-p. How?

Vp-p = 5V x (560/(5600+560)) = 5V x 0.0909 = 0.45V


RGB external resistor value
= (0.5 x (5600 + 75) - (75 x 5)) / (5 - 0.5)
= (0.5 x 5675 - 375) / 4.5
= 2462 / 4.5
= 550Ω

560Ω 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.

  • R842 (560Ω)
  • R843 (560Ω)
  • R844 (560Ω)

STEP 2: Connect RGB, Blanking

STEP 3: Blanking diode

To prevent current from flowing back into the OSD and causing interferences in RGB mods, it's necessary to include a diode in the blanking line. The absence of this diode is the main cause of such issues.

STEP 4: Sync and Audio

Sync and Audio can be connected to Video 2 input. You can also connect sync to the S-Video luma input to reduce the RGB shift.

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

On Sanyo CRT ChassisAVM-2507
CRT RGB inline resistor5.6kΩ
CRT RGB ground resistors removed560Ω
CRT RGB inline cap value0.1uF
Add blanking diode on chassis?Yes
RGB mux boardAVM-2507
Use RGB inline diodes on CRT chassis?No
Mux board Audio LR (R7, R8)1kΩ
Mux board RGB termination (R1, R2, R3)220Ω
Mux board RGB inline resistors (R4, R5, R6)560Ω
Mux board blanking diode (R9)1N4148
Mux board blanking ground resistor (R10)1.0kΩ

Buy your RGB mux board

Although the calculations were helpful, a dedicated tuner board was utilized to identify the optimal combination of RGB inline and termination resistance required to achieve the ideal color balance. After testing, it was discovered that a 220Ω termination provided the finest RGB image.


STEP 6: Service Menu and User Menu Adjustments

To attain the appropriate equilibrium between composite/s-video input and RGB input, numerous adjustments to both the Service Menu and User Menu were required for this set. Once set, you don't have adjust these when you switch inputs.

How to get into the Service Menu

While pressing the MENU key on the front of the TV, reconnect the AC power cord. The Service Menu Display will now appear.

I have only highlighted the values I changed here. You can scroll down to see the full service menu settings details

STEP 7: Attach the female SCART connector to TV

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

Pictures of the mod

Last update: