TV RGB mod thread

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Osirus
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Re: TV RGB mod thread

Post by Osirus »

Garage is back together and I'm working again. I snipped the jumpers on my PCB from the uC and the Jungle and am trying just straight RGB input as a last ditch effort. Essentially my circuit is now this:
Spoiler
Image
All I get with the blanking pulled high is a solid back screen - nothing.

Barring the possibility that modding this is not possible, which I don't believe since others have done it with this IC, could my source be setup wrong? I am using a MiSTer with an IO shield connected via VGA and using a VGA breakout connector on my TV. I have this in my mister.ini:

Code: Select all

ypbpr=0                ; set to 1 for YPbPr on VGA output.
composite_sync=1       ; set to 1 for composite sync on HSync signal of VGA output.
And the sync on green switch off.
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cyborc
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Re: TV RGB mod thread

Post by cyborc »

try wiring your 5v blanking to a 10k pot. According to the datasheet, the "max" voltage for ys to turn on is 3.6v, but it should probably still turn on with higher voltage...
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Osirus wrote:Garage is back together and I'm working again. I snipped the jumpers on my PCB from the uC and the Jungle and am trying just straight RGB input as a last ditch effort. Essentially my circuit is now this:
Spoiler
Image
All I get with the blanking pulled high is a solid back screen - nothing.

Barring the possibility that modding this is not possible, which I don't believe since others have done it with this IC, could my source be setup wrong? I am using a MiSTer with an IO shield connected via VGA and using a VGA breakout connector on my TV. I have this in my mister.ini:

Code: Select all

ypbpr=0                ; set to 1 for YPbPr on VGA output.
composite_sync=1       ; set to 1 for composite sync on HSync signal of VGA output.
And the sync on green switch off.
I have modified a set with the same Jungle. I notice that on the set I modded there were 0.1uF 50V electrolytic caps on the RGB lines with their positive leg closest to the jungle.

Apologies for the previous post.
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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
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Re: TV RGB mod thread

Post by MarkOZLAD »

Shiozaki wrote:
maxtherabbit wrote:
Shiozaki wrote:
The only thing I don't understand is what protects the microcontroller from getting 5v on the fast blanking pin without a switch, don't you add a diode or something?
Nothing protects it, nothing needs to. It is a TTL output pin, seeing 5V won't do it any harm
8bit guys video i guess left an impression on me that it could cause damage.
Only if there are no resistors between the 5V line and the blanking pin.
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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
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Re: TV RGB mod thread

Post by MarkOZLAD »

Shiozaki wrote:Hello everyone, I've since my last post set the other CRT aside and start working on this RCA model E13320, i really like the look of this one, and looking at the schematics it looks promising.

So if I'm understanding right I need to:

1. lift one leg of resistors RR41-RR38
2. Per the mux chat, since the factory inline resistors are 3.3ohms and there's no diode add 470ohm in the empty holes for RGB input mux.
3. remove the factor resistors to ground at RR534-RR537.

4 from Scart need RGB 75 resistor to ground, fast blanking needs factory value to ground (still new to this, reading values i haven't figured out, what is 820RO?)

5. feed-in RGB signal between the 3.3 and 470 resistors.

6. possibly change capacitors at CV505 CV507 CV509 to 100nfs.

The only thing I don't understand is what protects the microcontroller from getting 5v on the fast blanking pin without a switch, don't you add a diode or something?

Does this sound like I've got the right ideal or am I missing something?

service manual

schematic and pictures

You're looking in the right places but you are a bit off.

You don't want to lift the legs of R38, R39 and R40. They just remain there unchanged.

If you want to use the twist method like the 8 Bit Guy you want to remove resistors RR535, RR536 and RR537. You will replace each of these with 470R and 75R twisted together and soldered back into the holes of the resistors you just removed. The leg of the 75R will go into the hole that is grounded, the leg of the 470R will go into the other hole. The RGB will be injected into the legs that are twisted together. The 75R in the twisted resistors becomes your termination, no need to add more at the scart port.

Note that this assumes that RR535, RR536 and RR537 are through hole type resistors.

I wouldn't change the caps CV505 CV507 CV509 unless you have issues.

For blanking you can use the method the 8 Bit Guy uses in part II of his video. Lift the leg of RR41, solder a wire from the hole left by lifting the resistor to the outside leg of a SDPT switch. Run a 5V line to the other leg of the SPDT switch and then run a wire from the middle pin of the switch to the leg of RR41 that you lifted.
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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
Shiozaki
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Re: TV RGB mod thread

Post by Shiozaki »

MarkOZLAD wrote:
Shiozaki wrote:Hello everyone, I've since my last post set the other CRT aside and start working on this RCA model E13320, i really like the look of this one, and looking at the schematics it looks promising.

So if I'm understanding right I need to:

1. lift one leg of resistors RR41-RR38
2. Per the mux chat, since the factory inline resistors are 3.3ohms and there's no diode add 470ohm in the empty holes for RGB input mux.
3. remove the factor resistors to ground at RR534-RR537.

4 from Scart need RGB 75 resistor to ground, fast blanking needs factory value to ground (still new to this, reading values i haven't figured out, what is 820RO?)

5. feed-in RGB signal between the 3.3 and 470 resistors.

6. possibly change capacitors at CV505 CV507 CV509 to 100nfs.

The only thing I don't understand is what protects the microcontroller from getting 5v on the fast blanking pin without a switch, don't you add a diode or something?

Does this sound like I've got the right ideal or am I missing something?

service manual

schematic and pictures

You're looking in the right places but you are a bit off.

You don't want to lift the legs of R38, R39 and R40. They just remain there unchanged.

If you want to use the twist method like the 8 Bit Guy you want to remove resistors RR535, RR536 and RR537. You will replace each of these with 470R and 75R twisted together and soldered back into the holes of the resistors you just removed. The leg of the 75R will go into the hole that is grounded, the leg of the 470R will go into the other hole. The RGB will be injected into the legs that are twisted together. The 75R in the twisted resistors becomes your termination, no need to add more at the scart port.

Note that this assumes that RR535, RR536 and RR537 are through hole type resistors.

I wouldn't change the caps CV505 CV507 CV509 unless you have issues.

For blanking you can use the method the 8 Bit Guy uses in part II of his video. Lift the leg of RR41, solder a wire from the hole left by lifting the resistor to the outside leg of a SDPT switch. Run a 5V line to the other leg of the SPDT switch and then run a wire from the middle pin of the switch to the leg of RR41 that you lifted.
Thank you very much for the help, i was going to wire up my scart connector so 5v went to blanking from there/the console. are there better way then twisting them?
Last edited by Shiozaki on Fri Aug 21, 2020 1:55 am, edited 2 times in total.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Shiozaki wrote:Thank you very much for the help, i was going to wire up my scart connector so 5v went to blanking from there/the console.
If you want to do that...

Remove RR534. Twist together a 750 Ohm and a 75 Ohm resistor, 75 ohm leg goes to ground hole left from removal of RR534, 750 Ohm leg goes to the other... Connect scart pin 16 to twisted leg.

EDIT: If this leaves the blanking voltage from scart too low maybe a 680 ohm and a 150 Ohm would be better. 150 ohm on the ground side.
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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
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

cyborc wrote:try wiring your 5v blanking to a 10k pot. According to the datasheet, the "max" voltage for ys to turn on is 3.6v, but it should probably still turn on with higher voltage...
I originally had it around 3.5V I put in a smaller resistor to match the original circuit. Others with this chassis said they just put 5V on it and it worked.
Shiozaki
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Re: TV RGB mod thread

Post by Shiozaki »

MarkOZLAD wrote:
Shiozaki wrote:Hello everyone, I've since my last post set the other CRT aside and start working on this RCA model E13320, i really like the look of this one, and looking at the schematics it looks promising.

So if I'm understanding right I need to:

1. lift one leg of resistors RR41-RR38
2. Per the mux chat, since the factory inline resistors are 3.3ohms and there's no diode add 470ohm in the empty holes for RGB input mux.
3. remove the factor resistors to ground at RR534-RR537.

4 from Scart need RGB 75 resistor to ground, fast blanking needs factory value to ground (still new to this, reading values i haven't figured out, what is 820RO?)

5. feed-in RGB signal between the 3.3 and 470 resistors.

6. possibly change capacitors at CV505 CV507 CV509 to 100nfs.

The only thing I don't understand is what protects the microcontroller from getting 5v on the fast blanking pin without a switch, don't you add a diode or something?

Does this sound like I've got the right ideal or am I missing something?

service manual

schematic and pictures

You're looking in the right places but you are a bit off.

You don't want to lift the legs of R38, R39 and R40. They just remain there unchanged.

If you want to use the twist method like the 8 Bit Guy you want to remove resistors RR535, RR536 and RR537. You will replace each of these with 470R and 75R twisted together and soldered back into the holes of the resistors you just removed. The leg of the 75R will go into the hole that is grounded, the leg of the 470R will go into the other hole. The RGB will be injected into the legs that are twisted together. The 75R in the twisted resistors becomes your termination, no need to add more at the scart port.

Note that this assumes that RR535, RR536 and RR537 are through hole type resistors.

I wouldn't change the caps CV505 CV507 CV509 unless you have issues.

For blanking you can use the method the 8 Bit Guy uses in part II of his video. Lift the leg of RR41, solder a wire from the hole left by lifting the resistor to the outside leg of a SDPT switch. Run a 5V line to the other leg of the SPDT switch and then run a wire from the middle pin of the switch to the leg of RR41 that you lifted.
tiny surface mount, I guess I could try and tombstone some components on purpose, IDK, any input is always welcome.

https://imgur.com/a/scTNXie
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BazookaBen
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Re: TV RGB mod thread

Post by BazookaBen »

Can anybody recommend a few videos to watch before attempting my first RGB mod?

Will be doing it on a tiny composite only Sony KV-13FM12
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

BazookaBen wrote:Can anybody recommend a few videos to watch before attempting my first RGB mod?

Will be doing it on a tiny composite only Sony KV-13FM12
Your TV has a BA-5 chassis. This thread covers it.

viewtopic.php?f=6&t=63622
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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
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Re: TV RGB mod thread

Post by MarkOZLAD »

Shiozaki wrote:
tiny surface mount, I guess I could try and tombstone some components on purpose, IDK, any input is always welcome.

https://imgur.com/a/scTNXie
Surface mount makes it a pain but all the same concepts apply are there any jumpers on the RGB circuits lines that could provide an easy in?
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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
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BazookaBen
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Re: TV RGB mod thread

Post by BazookaBen »

Awesome thanks.

I'm also going to attempt to add s-video, and it looks like has some has done that here:

viewtopic.php?f=6&t=65583

so thanks to you guys I don't have to expend too much mental energy on this haha!
Romariu
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Re: TV RGB mod thread

Post by Romariu »

How to rgb mod a SAMSUNG CL21A551ML?
Please :(
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

Romariu wrote:How to rgb mod a SAMSUNG CL21A551ML?
Please :(
Looks like a single (integrated OSD/Jungle) board however, the chip looks like it has unused RGB In pins (12, 13, 14) you may be able to use.

https://www.eserviceinfo.com/download_s ... rlid=89246
Romariu
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Re: TV RGB mod thread

Post by Romariu »

Thank you very much for your help Osirus.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

New TV: Sony KV-20M10. Chassis is BA-2.

The OSD circuit is Digital RGB, but:

https://html.alldatasheet.com/html-pdf/ ... 465AS.html

It has separate Analog RGB in pins on 16, 17, and 18; as well as separate Ym/Ys pins for Analog RGB on 14 and 15. I haven't opened up the TV yet, but on the schematic it looks like the Analog RGB inputs are just grounded:

https://www.manualslib.com/manual/95618 ... =29#manual

Anyone done one of these? Looks cautiously promising. 75ohm terminated RGB with 0.1uF caps to the Analog inputs and > 1.0 to 15 sound like a plan?
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cyborc
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Re: TV RGB mod thread

Post by cyborc »

Osirus wrote:New TV: Sony KV-20M10. Chassis is BA-2.

The OSD circuit is Digital RGB, but:

https://html.alldatasheet.com/html-pdf/ ... 465AS.html

It has separate Analog RGB in pins on 16, 17, and 18; as well as separate Ym/Ys pins for Analog RGB on 14 and 15. I haven't opened up the TV yet, but on the schematic it looks like the Analog RGB inputs are just grounded:

https://www.manualslib.com/manual/95618 ... =29#manual

Anyone done one of these? Looks cautiously promising. 75ohm terminated RGB with 0.1uF caps to the Analog inputs and > 1.0 to 15 sound like a plan?

Sony have been known to disable unused RGB jungle inputs via software. hopefully this one isn't like that.
zFleeman
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Re: TV RGB mod thread

Post by zFleeman »

Hi, everyone. I am trying to replicate the Spongebob RGB mod that arithmaldor posted about a couple of years ago. Their model was a SB315 (with the spongebob themed menus) but mine is an SB314 -- plain menus. I went ahead and ordered all of the resistors in this post, assuming that my mod would be identical to arithmaldor's.

Well, the OSD source is a different-looking chip entirely, which makes sense, but I don't think that should be a big problem. My main problem is that there's a diode on the blanking osd inline instead of a resistor, like arithmaldor's.

arithmaldor's board SB314 -- resistor on blanking osd inline
Image

This has me wondering if I counted my chickens before they hatched and bought all of my resistors ahead of time. The inline resistors for my set's RGB are 1k, which is what was on the SB315. The jungle chip is also the same model.

What should I do about this diode? Should I still follow this schematic? Also, when pulling 5v for blanking... where do I find the source for that? The tinkerplunk blog post says
I replaced the existing blanking resistors with the values from the schematic, and then just put a wire from a 5V signal on the board to the non-ground leg of the grounding resistor.
but I don't know where to find that.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

zFleeman wrote: Also, when pulling 5v for blanking... where do I find the source for that?
Really, anywhere you can. Look at the schematic for a pin labeled "Vcc" or "Supply Voltage", something like that. Then check the datasheet to see its value, they aren't always 5V so you may have to do a voltage divider once you find it.
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Re: TV RGB mod thread

Post by zFleeman »

Osirus wrote:
zFleeman wrote: Also, when pulling 5v for blanking... where do I find the source for that?
Really, anywhere you can. Look at the schematic for a pin labeled "Vcc" or "Supply Voltage", something like that. Then check the datasheet to see its value, they aren't always 5V so you may have to do a voltage divider once you find it.
Ah, okay, I see where I can get that from the jungle chip.

Another wrinkle in this situation: The RGB lines do not have any resistors between them and ground. The blanking grounding resistor has a value of 2.17kO.

So, in summary, here are the differences with this board (SB314) that I'm noticing. Let me know if they change this mod from SB315.
  • Inline resistor for blanking is a diode, not a resistor. Can this be replaced with a 180 ohm like in Syntax's schematic?
  • The only grounding resistor present on the board was a 2.17kO resistor. This seems like it was different from arithmaldor's. Are the empty resistor slots still okay to be terminated with a 75 ohm and combined with a 360 ohm for my external RGB lines?
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matt
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Re: TV RGB mod thread

Post by matt »

Osirus wrote:New TV: Sony KV-20M10. Chassis is BA-2.

The OSD circuit is Digital RGB, but:

https://html.alldatasheet.com/html-pdf/ ... 465AS.html

It has separate Analog RGB in pins on 16, 17, and 18; as well as separate Ym/Ys pins for Analog RGB on 14 and 15. I haven't opened up the TV yet, but on the schematic it looks like the Analog RGB inputs are just grounded:

https://www.manualslib.com/manual/95618 ... =29#manual

Anyone done one of these? Looks cautiously promising. 75ohm terminated RGB with 0.1uF caps to the Analog inputs and > 1.0 to 15 sound like a plan?
I did one on a KV-13TR28, which is a BA-1 chassis but has the same jungle chip. I used +5v for blanking (with a 1K resistor), 0.1 uF caps, and 75 ohm termination.

In my case, that TV was practically built to be RGB modded. It has a closed caption card that, if removed, yields a pin header with all the necessary pins and you can do the RGB mod with no soldering. Also, there's a horizontal position switch that can be rerouted to the blanking switch (if you use a DPDT) to maintain screen position when switching between RGB and composite. One of the nice things about this jungle chip is that the analog RGB works fine with the TV's brightness and contrast controls and doesn't interfere with the OSD.

It couldn't hurt to try, but page 27 of the datasheet does seem to indicate that the RGB inputs can be disabled by the micom.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

matt wrote:
Osirus wrote:New TV: Sony KV-20M10. Chassis is BA-2.

The OSD circuit is Digital RGB, but:

https://html.alldatasheet.com/html-pdf/ ... 465AS.html

It has separate Analog RGB in pins on 16, 17, and 18; as well as separate Ym/Ys pins for Analog RGB on 14 and 15. I haven't opened up the TV yet, but on the schematic it looks like the Analog RGB inputs are just grounded:

https://www.manualslib.com/manual/95618 ... =29#manual

Anyone done one of these? Looks cautiously promising. 75ohm terminated RGB with 0.1uF caps to the Analog inputs and > 1.0 to 15 sound like a plan?
I did one on a KV-13TR28, which is a BA-1 chassis but has the same jungle chip. I used +5v for blanking (with a 1K resistor), 0.1 uF caps, and 75 ohm termination.

In my case, that TV was practically built to be RGB modded. It has a closed caption card that, if removed, yields a pin header with all the necessary pins and you can do the RGB mod with no soldering. Also, there's a horizontal position switch that can be rerouted to the blanking switch (if you use a DPDT) to maintain screen position when switching between RGB and composite. One of the nice things about this jungle chip is that the analog RGB works fine with the TV's brightness and contrast controls and doesn't interfere with the OSD.

It couldn't hurt to try, but page 27 of the datasheet does seem to indicate that the RGB inputs can be disabled by the micom.
Gonna be a bit of a pain to get to. I'll have to snip the pins or try to desolder them and pull them up since all three are soldered directly to a single pad with one resistor pulling them all to ground. No jumpers or legs available to use.

I'm thinking the best way to see if they are enabled and moddable is to pull Ys high and put R, G, or B onto one of the pins (won't matter since all three are tied together) and see if I get a white screen or something?
zFleeman
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Re: TV RGB mod thread

Post by zFleeman »

Spongebob TV SB314 Mod Update

It isn't working. I got impatient (a major character flaw of mine) and placed the resistors from Syntax's diagram on the board and hooked everything up, and it's not working. Whenever I disconnect the 5v blanking wire, I can see the original channel select/source blue screen, but there isn't an OSD. I don't think anything is broken, but it's clear to me that I am not using the correct resistor/diode values, and I think I need some more help (more information about this post) if anybody can offer it.

Sharp 13KM100

I just picked this 13 inch crt from a coworker, and I'm actually more hopeful that I can get this one modded with your help. Page 15 of this service manual pretty much shows everything I need to know, I think. I have located the jungle and osd chips on the board I removed from the TV, but I feel like I'm at square one.

I want to RGB mod this thing, and I don't really care if it's the non-OSD mux/toggle switch method.

If I'm looking at the inline resistor values correctly on the source chip (6,800), should I go ahead and order some 1,100 resistors according to this table?

The resistors to ground right before the jungle are 1.8k. Would these be swapped with 75ohm?

Source
Image

Jungle
Image

Thank you for any help. I'm really excited to get these two up and running. Such a neat project.
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Re: TV RGB mod thread

Post by MarkOZLAD »

zFleeman wrote:Spongebob TV SB314 Mod Update

It isn't working. I got impatient (a major character flaw of mine) and placed the resistors from Syntax's diagram on the board and hooked everything up, and it's not working. Whenever I disconnect the 5v blanking wire, I can see the original channel select/source blue screen, but there isn't an OSD. I don't think anything is broken, but it's clear to me that I am not using the correct resistor/diode values, and I think I need some more help (more information about this post) if anybody can offer it.

Sharp 13KM100

I just picked this 13 inch crt from a coworker, and I'm actually more hopeful that I can get this one modded with your help. Page 15 of this service manual pretty much shows everything I need to know, I think. I have located the jungle and osd chips on the board I removed from the TV, but I feel like I'm at square one.

I want to RGB mod this thing, and I don't really care if it's the non-OSD mux/toggle switch method.

If I'm looking at the inline resistor values correctly on the source chip (6,800), should I go ahead and order some 1,100 resistors according to this table?

The resistors to ground right before the jungle are 1.8k. Would these be swapped with 75ohm?

Source
Image

Jungle
Image

Thank you for any help. I'm really excited to get these two up and running. Such a neat project.

For RGB remove resistors R803, R804, R805

The inlines in the RGB lines are 6800 Ohm so the mux resistors are 1100 ohm (1000 ohm would likely be fine).

So send 75 ohm terminated RGB lines into 1100 ohm resistors and then connect to the RGB circuits. The legs of R2024, R2025 and R2026 farthest from micro controller might be good spots to attach wires.

For blanking use the 8 Bit Guy RGB mod part 2 method. Lift the leg of R2027 that is closest to the micro controller and inject 5V into it.
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
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matt
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Re: TV RGB mod thread

Post by matt »

MarkOZLAD wrote:The inlines in the RGB lines are 6800 Ohm so the mux resistors are 1100 ohm (1000 ohm would likely be fine).

So send 75 ohm terminated RGB lines into 1100 ohm resistors and then connect to the RGB circuits. The legs of R2024, R2025 and R2026 farthest from micro controller might be good spots to attach wires.

For blanking use the 8 Bit Guy RGB mod part 2 method. Lift the leg of R2027 that is closest to the micro controller and inject 5V into it.
I did an RGB mod to a 13K-M100 a while back. 1k ohm resistors worked well.

RGB on this TV is very dark with 75 ohm termination (I think I remember reading that this jungle IC expects 1v p-p). In my case I was able to get a satisfactory picture by adjusting the flyback pot and the RGB cutoffs in the service menu, but there may be a better way to deal with this.
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Re: TV RGB mod thread

Post by MarkOZLAD »

1.0Vp-p RGB huh? Very interesting.

I wonder if the termination resistor should be changed to 180 ohm. That should give 1.0Vp-p from external RGB.

Would then use 1600 ohm mux resistors.
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
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Re: TV RGB mod thread

Post by zFleeman »

MarkOZLAD wrote:1.0Vp-p RGB huh? Very interesting.

I wonder if the termination resistor should be changed to 180 ohm. That should give 1.0Vp-p from external RGB.

Would then use 1600 ohm mux resistors.
I can do either one. Which would you recommend starting with?
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Re: TV RGB mod thread

Post by cyborc »

MarkOZLAD wrote:1.0Vp-p RGB huh? Very interesting.

I wonder if the termination resistor should be changed to 180 ohm. That should give 1.0Vp-p from external RGB.

Would then use 1600 ohm mux resistors.
I recently modded a JVC with this jungle. (ta1268n)

I thought it expected 0.5vpp based on this note in the datasheet

Image

The downside to this jungle is the brightness/contrast controls on the TV have no effect on the picture in RGB.
MarkOZLAD
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Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

Now I’m confused about which models we are discussing.
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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
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