TV RGB mod thread

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MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Espetacular !
I saw the connector ! it´s super easy next to the mod region! will put a fast connect just like i´m using, to turn the 5v on/off just unplugin the little cable!
Give a look to the photos !

https://photos.app.goo.gl/4crnTtus6IoSuG293

Wow now i´m confident that will work !

Thanks a lot!
Marcos
Ah yes, I see it now. In the perfect position really.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Now i'm confusing too, lol!
In my case on the J281, the pin 2 should be the F Blank ?
The pin 3 looks like the blue.

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Now i'm confusing too, lol!
In my case on the J281, the pin 2 should be the F Blank ?
The pin 3 looks like the blue.

Thanks
Marcos
My mistake. You are correct. Pin 2 is EXT FBAL IN. The schematic is confusing there, badly drawn.

For J281
1 is Ground
2 is FBAL IN
3 is EXT BLUE IN
4 is EXT GREEN IN
5 is EXT RED IN

When I checked your photo I noticed that you have it wired correctly already.
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MarkOZLAD
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Excelent!
Already get the 5v from you suggest, installed the 1k ohms on the h and v sync, just waiting for the 75ohms to come from mail!
The "frankstein" is almost done!

https://photos.app.goo.gl/Xn3nxLsImiPJyOL22

Thanks
Marcos
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Has anyone had an issue where the osd is really really washed and dim even before modding?
I have a trinitron set that has bright colorful composite but when I run rgb it's washed out. Same with the OSD.
75ohm termination then clamped with 100n monolithic caps.
Rgb in place of teletext(2nd RGB input) osd RGB lines unchanged.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Excelent!
Already get the 5v from you suggest, installed the 1k ohms on the h and v sync, just waiting for the 75ohms to come from mail!
The "frankstein" is almost done!

https://photos.app.goo.gl/Xn3nxLsImiPJyOL22

Thanks
Marcos
That's some really neat looking work. Any idea how long it will take to get the 75Ohm resistors? I'm really keen to see this working! If you've got the 82Ohm resistors I'd give them a shot while you wait, I'm impatient like that!
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

You would be hard pressed trying to find a difference between 82 and 75 ohm. Id try it without resistors even just to check it works but that's me.

Why did you have to take the chassis apart?
All my mods have been in situ, i only ever slide the board out slightly and jam it on an angle if I need jungle access or to remove surface mounted components.
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Can you imagine my anxiety, lol
My lucky the post office will delivery them tomorrow morning!
I think tomorrow in the end of day will be able to test it!

Will definely show pics, videos, etc from all footage working.

With every detail check and re-checked the probaly the mod to work is very high!

Hope tomorrow will bring good news!

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Can you imagine my anxiety, lol
My lucky the post office will delivery them tomorrow morning!
I think tomorrow in the end of day will be able to test it!

Will definely show pics, videos, etc from all footage working.

With every detail check and re-checked the probaly the mod to work is very high!

Hope tomorrow will bring good news!

Thanks
Marcos
Marcos,

I'm anxious and I'm half a world away!
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MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Can you imagine my anxiety, lol
My lucky the post office will delivery them tomorrow morning!
I think tomorrow in the end of day will be able to test it!

Will definely show pics, videos, etc from all footage working.

With every detail check and re-checked the probaly the mod to work is very high!

Hope tomorrow will bring good news!

Thanks
Marcos

Marcos,

I have been checking out the datasheet for the TDA8374A Jungle Chip. It indicates that if you put 4V or more on the blanking pin it will make the screen black for OSD insertion.

On page 32 of the datasheet:

Vi

input voltage to insert black level
at the RGB outputs to facilitate
‘On Screen Display’ signals
being applied to the outputs

4 - - V

I would suggest you definitely want to put a 10K potentiometer on the 5V Blanking lines to allow you to vary the voltage as Syntax suggested.
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MarkOZLAD
OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

MarkOZLAD wrote:
m.andrade1 wrote:Hello Mark
Can you imagine my anxiety, lol
My lucky the post office will delivery them tomorrow morning!
I think tomorrow in the end of day will be able to test it!

Will definely show pics, videos, etc from all footage working.

With every detail check and re-checked the probaly the mod to work is very high!

Hope tomorrow will bring good news!

Thanks
Marcos

Marcos,

I have been checking out the datasheet for the TDA8374A Jungle Chip. It indicates that if you put 4V or more on the blanking pin it will make the screen black for OSD insertion.

On page 32 of the datasheet:

Vi

input voltage to insert black level
at the RGB outputs to facilitate
‘On Screen Display’ signals
being applied to the outputs

4 - - V

I would suggest you definitely want to put a 10K potentiometer on the 5V Blanking lines to allow you to vary the voltage as Syntax suggested.
You can't just put 5v on one leg and blanking center if the legs starts high because your just applying voltage to voltage.
You need to be able to drain that pin much like the L2Fil pin.

So 5v one side ground the other side and blanking center

Personally I tend to use 2x2.2k resistors as a voltage divider and it usually works.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Syntax wrote:You can't just put 5v on one leg and blanking center if the legs starts high because your just applying voltage to voltage.
You need to be able to drain that pin much like the L2Fil pin.

So 5v one side ground the other side and blanking center

Personally I tend to use 2x2.2k resistors as a voltage divider and it usually works.
Ah ok, fair point, I was thinking about how I would do my mods and I always have an on/off switch on the blanking line. I would then use the potentiometer as a variable resistor.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark / Syntax
Hmm change on plans, so just check if i understand well, in one external leg have to wire a gnd (can i use the pin 1 from the J281 ?), on another external leg the 5v line Mark suggest, and on the middle leg the wire that goes to F Blank (pin 2 to J281), is that correct?

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark / Syntax
Hmm change on plans, so just check if i understand well, in one external leg have to wire a gnd (can i use the pin 1 from the J281 ?), on another external leg the 5v line Mark suggest, and on the middle leg the wire that goes to F Blank (pin 2 to J281), is that correct?

Thanks
Marcos
Try without the potentiometer first. If you just get a black screen then try adding the potentiometer.

Yes you can use pin 1 of J281 as ground.

Yes you have the wiring as per Syntax' instructions. I've burned out a couple of potentiometers so I won't tell you how to do it.
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MarkOZLAD
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Another option would be to wire the potentiometer as a variable resistor on the 5V line and then use the quick connect as on off switch.

Set a resistance. Connect the wires. See what happens. Keep trying till it works.
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MarkOZLAD
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Perfect! Will try the mod first without the potenciometer and see if it works.
Will receive the 75ohms today, so if everything goes well i will test today on the end of day!

Thanks again
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Perfect! Will try the mod first without the potenciometer and see if it works.
Will receive the 75ohms today, so if everything goes well i will test today on the end of day!

Thanks again
Marcos
Hop it goes well.

Getting ground from pin 4 of J380 would be a neat option too.
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MarkOZLAD
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Hmm, seems more clean choice a separate gnd to serv the potenciometer, good hint!
Look what came earlier in the morning !

https://photos.app.goo.gl/77LTAEZtrpthi1Hg2

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote: Look what came earlier in the morning !

https://photos.app.goo.gl/77LTAEZtrpthi1Hg2
Just how many TVs are you going to mod?
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MarkOZLAD
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
hehe, I told you Brazil everthing is dificult! the sellers has a minimum order online 100pçs, wow, just need 3.

Thanks
Marcos
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
The mod is ready for some HV juice ! on the end of the day will be able to test it.

https://photos.app.goo.gl/LG0NqNpLOTjThJt22

Let´s see if i will bring good news for all !

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
The mod is ready for some HV juice ! on the end of the day will be able to test it.

https://photos.app.goo.gl/LG0NqNpLOTjThJt22

Let´s see if i will bring good news for all !

Thanks
Marcos

Looks really good. I always find it hard to do neat 75ohm termination wiring. Yours looks fine.
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MarkOZLAD
OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark and Everyone
Well i tested the mod, it works partialy, the link with the footage is bellow!
Let me explain what happened, it´s kind bizarre to explain, lol, let me try, when i turn the tv on, the screen looks like phantom black only with the contours of the image showed, but when i click to bring the menu (osd) to screen, the strange happens, the rgb footage only show in the areas where the menu(osd) is active, is it bizarre or not!
So the signal is mixing osd+rgb mod on the same place, mixed.
But let me tell you, i´m already excited because the image even with the shadow of the menu backwords is fantastic, so now, we have to figure out what could be wrong here, let me show the videos and images!

https://photos.app.goo.gl/o66JEplATofUilaz2

Just a note Mark, i think the rgb image is there very dim, and it's not mixin the osd, just when the menu appears it blends toghether, i didn´t install the potentiometer like Syntax suggest, get the 5v from where you suggest, do you think somehow the mod are not been feeding with the right voltage, and only when the osd are trigger by the menu, the rgb signal become active ?
I put a footage from an AV normal signal and trigger the OSD, it´s dark, strange dont you think ?

Any ideas, where i can attack or re-check ?

Thanks a lot
Marcos
Last edited by m.andrade1 on Fri Sep 01, 2017 10:30 pm, edited 1 time in total.
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Bratwurst
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Re: TV RGB mod thread

Post by Bratwurst »

Marcos, looks like you need to cut/interrupt the RGB signals coming from the OSD source when you are injecting your PC/emulator RGB. Not sure if you've done that since I haven't followed too closely but I don't see a 4PDT switch anywhere to accomplish that.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Marcos,

Ok, firstly there should be no need for a 4PT switch or snipping of the OSD lines in the mod we are attempting here. We are instead attempting to inject the RGB into an existing "External RGB" port that was initially an unpopulated header on the board. You can "disable" the OSD by not enabling it....

Let's look at the major positives of what you have achieved.

1) The RGB you are injecting IS getting to the Jungle IC
2) The RGB IS syncing perfectly
3) The RGB and sync levels you are providing from the adapted VGA signal appear good

Now let's look at the symptoms...

When you do not have the OSD enabled, the "contours" you see are from the sync signal. This means that the RGB insertion is not enabled (obviously).

When you hit the menu button, the OSD is enabled, RGB insertion turns on. You get a mux of the OSD and your external RGB signal. This makes sense because the OSD and External RGB share the same lines.

I believe the blanking/RGB Insertion is not being triggered properly because of incorrect voltage to the Fast Blanking pin. Try changing the voltage you are sending through the blanking signal.

To me this looks very promising. If anyone told you RGB modding was easy and would always go smoothly they haven't done it!

Cheers,

Mark
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Bratwurst
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Re: TV RGB mod thread

Post by Bratwurst »

Right, I understand now. I agree the blanking voltage likely needs to be adjusted. If there's a datasheet on the jungle chip in question there might be mention of the value needed. Getting a read on the voltage to the blanking pin with the menu active probably would clue in the value it needs.
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
You are right, we are progressing very well, indeed!
Let me tell you even with the image kind blend with the menu for me is already fantastic, no chassi i had till today, had so many beaultifull image, with geomatry, and colors perfect.
So i have this impression too, the signal is there, but it is not "trigger" by the "f blank", now i dont know where to get the voltage from, what do you think in the old idea that run it from the pc power suplly, and put a potentiometer to be abble to adjust it on the fly, maybe it can "triger" the chip.
Have no more ideas left, but the will to ser it happens is big!

Thank a lot
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
You are right, we are progressing very well, indeed!
Let me tell you even with the image kind blend with the menu for me is already fantastic, no chassi i had till today, had so many beaultifull image, with geomatry, and colors perfect.
So i have this impression too, the signal is there, but it is not "trigger" by the "f blank", now i dont know where to get the voltage from, what do you think in the old idea that run it from the pc power suplly, and put a potentiometer to be abble to adjust it on the fly, maybe it can "triger" the chip.
Have no more ideas left, but the will to ser it happens is big!

Thank a lot
Marcos
Need to add a potentiometer to the 5V line you already have.
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MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Understand, that way like Syntax recomend, with the gnd on one of the legs, or diectly like you suggest without the gnd?

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

My record with potentiometers isn't good. I've tried to use them twice and they went up in smoke both times! So I'd follow Syntax' instructions, not mine.

Perhaps you can try just adding resistors to the 5V line. Got any more of those 1000 ohm ones lying around?
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
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