TV RGB mod thread

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matt
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Re: TV RGB mod thread

Post by matt »

DemoNight wrote:I might try and see if I can get sync on the S Video line just to see if that fixes the left shift but I dunno if I'll even bother since the service menu will surely fix the issue.
You should run sync through S Video. You'll still have to adjust the position in the service menu, but it will be a lot less - the composite input runs through the TV's comb filter which adds a lot of delay.

On some consoles, the image is shifted far enough that it throws off the white balance. With composite, it's not possible to move the picture far enough to avoid this.
DemoNight
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Re: TV RGB mod thread

Post by DemoNight »

matt wrote:
DemoNight wrote:I might try and see if I can get sync on the S Video line just to see if that fixes the left shift but I dunno if I'll even bother since the service menu will surely fix the issue.
You should run sync through S Video. You'll still have to adjust the position in the service menu, but it will be a lot less - the composite input runs through the TV's comb filter which adds a lot of delay.

On some consoles, the image is shifted far enough that it throws off the white balance. With composite, it's not possible to move the picture far enough to avoid this.

for testing can I just cut up a S Video plug, solder pin 20 and 18 of the scart plug to pin 3 and 1 of the svideo cable? Apparently you need a sense circuit on some sort for the S Video plug to be active, could I just leave a chopping off s video plug in the port at all times even after I solder to the inside of it? I really don't have a clue what I'm doing and only got as far as I am now by the good graces of the posters here.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

You probably don't even need a separate ground, they should all be tied together.

Yes, you can just plug a dummy S-video connector into the jack to activate the input instead of rigging up a switch.
DemoNight
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Re: TV RGB mod thread

Post by DemoNight »

Osirus wrote:You probably don't even need a separate ground, they should all be tied together.

Yes, you can just plug a dummy S-video connector into the jack to activate the input instead of rigging up a switch.

Finally had some time to mess with the TV, wired up sync to the luma pin on the S Video plug and it worked perfect and shifted the picture over properly. If I wanted to setup the s video to not need the plug in it, i'm assuming i'll need to set up a switch? I think I gotta pull something to ground but i'm not sure what. I also come to the conclusion that 330ohms in line and 75 ohms to ground is not enough resistance, right now I doubled up the 75ohm resistors to ground and it's a touch to dark. I'm gonna order 100ohm resistors for the ground. I know I seen other people in this thread say Sony CRT's need 100ohms anyways.
camtron47
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Re: TV RGB mod thread

Post by camtron47 »

So I did the OSD mux mod on my BG-3S chassis and it worked properly for about 5 minutes and then everything turned purple due to losing green input. The OSD is purple too (even on composite input).
I've done a quick check of the green circuit and it doesn't seem to be grounded inappropriately anywhere. So all I can think of is the 100nF capacitor I put in went bad (seems unlikely?) or the green input on the jungle got fried. Is that possible?
Has anyone seen this happen before?
Thanks
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matt
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Re: TV RGB mod thread

Post by matt »

DemoNight wrote:
Osirus wrote:You probably don't even need a separate ground, they should all be tied together.

Yes, you can just plug a dummy S-video connector into the jack to activate the input instead of rigging up a switch.

Finally had some time to mess with the TV, wired up sync to the luma pin on the S Video plug and it worked perfect and shifted the picture over properly. If I wanted to setup the s video to not need the plug in it, i'm assuming i'll need to set up a switch? I think I gotta pull something to ground but i'm not sure what. I also come to the conclusion that 330ohms in line and 75 ohms to ground is not enough resistance, right now I doubled up the 75ohm resistors to ground and it's a touch to dark. I'm gonna order 100ohm resistors for the ground. I know I seen other people in this thread say Sony CRT's need 100ohms anyways.
For my Trinitron mods, I've been using 820 ohms inline and 75 to ground. This works for me.

The S-Video jack on your TV will have a pin that's grounded when you plug in an S-Video cable. You'll be able to see which one it is, since it will touch the outer shield of the S-Video plug when it's connected. Figure out which one it is with a multimeter, and wire it up in tandem with the blanking switch.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

If going off the schematic, look for a trace running from the S-video connector to an IC labeled "Sense". Pull that line to ground to activate S-video on that input instead of Composite.
coredump
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Re: TV RGB mod thread

Post by coredump »

Ok so I modded a 27V66 using i2c stuff and enabling the unused RGB input, described it here viewtopic.php?f=6&t=68917

I can't figure out how to disappear with the OSD showing 'VIDEO1' on my screen tho. Pressing the display button on the remote means nothing. I tried putting 0.8 V on YS2 but that dims the whole output, so I guess that's to show the menu and make the OSD MORE visible not vice versa.

The YS2 is pulled down via a 10k resistor, but I measured some 20mV on it. Tried grounding it directly and that makes the OSD super faint, basically transparent, but that also prevents me from using the menu/volume.

Any ideas? I tried to check on the i2c registers but I can't find anything glaring suggesting how that works.

I am getting the Sync from the S-Video input, and the i2c registers related to Video selection are matching that. I am wondering if the TV is actually waiting for some signal on the C input to disappear with that OSD, as in, it thinks it's not connected because it has Luma but no Chroma.
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golden potato
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Re: TV RGB mod thread

Post by golden potato »

I successfully modded a Sony KV-13TR28 by removing the closed captioning card and intercepting the RGB lines and blanking signal from its socket. The remarkable part of this mod is the lack of a physical switch or SCART connector (I prefer BNC). The rear composite video input (VIDEO 1) is now a dedicated RGBS input and can be switched between it and front composite (VIDEO 2) and TV inputs using only the factory TV/VIDEO button or remote.

I accomplished this by first noticing that IC101 has two binary control signals to control which input the AV switcher (IC401) selects. A truth table for the control lines is included in the schematic. Too easy! I scratched together some simple logic using a few instances of one quad NAND gate to drive the RGB blanking signal when VIDEO 1 is selected. At first I intercepted the control lines at IC401 because it was more convenient, but after the signals travel through 12k ohm of resistors, they weren’t strong enough to sink the logic gate inputs down to a reliable zero. I later moved to tapping into pins 6 and 7 on IC101 which worked great.

One thing to note is that the RGB blanking signal (originally for closed captioning) can also still be driven by the IC101, but it’s through a large enough resistor that if it “fights” my NAND gate output, it doesn’t create enough current to harm anything. However, I’m just not going to try to turn on closed captioning and find out. Also, it would be pointless to try because I removed the closed captioning card altogether!

Imgur album here: https://imgur.com/a/4VqjCR7

The next set I’ll do is a KV-27V42. It has an unused RGB input on its jungle IC. As another commenter mentioned in this thread, it’s jungle IC data sheet is unavailable to determine if it’s an analog or digital RGB input, so I’m just going to try it and find out. Unfortunately, its AV switcher IC isn’t controlled via binary control signals but instead the more common serial control (I2C). I think for this TV I’ll try to setup a small microcontroller to sniff the I2C bus and bring the RGB blanking signal high when it detects that the AV switcher IC was told to switch to whatever input I commandeer for sync input (probably the SVIDEO input). However it would be nice to preserve the use of the SVIDEO input, so maybe I’ll throw a physical switch on the back to disable it so SVIDEO works like stock.
Last edited by golden potato on Sat Aug 14, 2021 4:12 am, edited 1 time in total.
-Golden
DemoNight
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Re: TV RGB mod thread

Post by DemoNight »

matt wrote: For my Trinitron mods, I've been using 820 ohms inline and 75 to ground. This works for me.

The S-Video jack on your TV will have a pin that's grounded when you plug in an S-Video cable. You'll be able to see which one it is, since it will touch the outer shield of the S-Video plug when it's connected. Figure out which one it is with a multimeter, and wire it up in tandem with the blanking switch.
That seems like a lot of resistance, does the resistance on the inline side just do less than when you put resistors to ground? With my 150ohm to ground and 330 ohm inline the picture is a touch to dark.
Osirus wrote:If going off the schematic, look for a trace running from the S-video connector to an IC labeled "Sense". Pull that line to ground to activate S-video on that input instead of Composite.
Will give it a look, have a DPST on the way so I can switch the sense circuit and blanking circuit cleanly.
coredump wrote:Ok so I modded a 27V66 using i2c stuff and enabling the unused RGB input, described it here viewtopic.php?f=6&t=68917

I can't figure out how to disappear with the OSD showing 'VIDEO1' on my screen tho. Pressing the display button on the remote means nothing. I tried putting 0.8 V on YS2 but that dims the whole output, so I guess that's to show the menu and make the OSD MORE visible not vice versa.

The YS2 is pulled down via a 10k resistor, but I measured some 20mV on it. Tried grounding it directly and that makes the OSD super faint, basically transparent, but that also prevents me from using the menu/volume.

Any ideas? I tried to check on the i2c registers but I can't find anything glaring suggesting how that works.

I am getting the Sync from the S-Video input, and the i2c registers related to Video selection are matching that. I am wondering if the TV is actually waiting for some signal on the C input to disappear with that OSD, as in, it thinks it's not connected because it has Luma but no Chroma.
On my mod, I only have the the luma pin connected and I don't have any issues with the display going away. I have a AA2D chassis though.
camtron47
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Re: TV RGB mod thread

Post by camtron47 »

camtron47 wrote:So I did the OSD mux mod on my BG-3S chassis and it worked properly for about 5 minutes and then everything turned purple due to losing green input. The OSD is purple too (even on composite input).
I've done a quick check of the green circuit and it doesn't seem to be grounded inappropriately anywhere. So all I can think of is the 100nF capacitor I put in went bad (seems unlikely?) or the green input on the jungle got fried. Is that possible?
Has anyone seen this happen before?
Thanks
I fixed my purple problem. It was either the green input capacitor was dodgy or more likely I'd soldered it on poorly because by replacing it with a fresh cap and double checking the joints, it all looked good and now I've got full colour again.
Next thing I've noticed is that the picture is slightly but noticeably washed out when switching to RGB. When turning on the blanking switch a black background visibly turned a bluish grey for example. Is this common? Do I need more input resistance as mention in recent posts? Or am I fine to just recalibrate the brightness to better suit the RGB input?
DemoNight
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Re: TV RGB mod thread

Post by DemoNight »

camtron47 wrote:
camtron47 wrote:So I did the OSD mux mod on my BG-3S chassis and it worked properly for about 5 minutes and then everything turned purple due to losing green input. The OSD is purple too (even on composite input).
I've done a quick check of the green circuit and it doesn't seem to be grounded inappropriately anywhere. So all I can think of is the 100nF capacitor I put in went bad (seems unlikely?) or the green input on the jungle got fried. Is that possible?
Has anyone seen this happen before?
Thanks
I fixed my purple problem. It was either the green input capacitor was dodgy or more likely I'd soldered it on poorly because by replacing it with a fresh cap and double checking the joints, it all looked good and now I've got full colour again.
Next thing I've noticed is that the picture is slightly but noticeably washed out when switching to RGB. When turning on the blanking switch a black background visibly turned a bluish grey for example. Is this common? Do I need more input resistance as mention in recent posts? Or am I fine to just recalibrate the brightness to better suit the RGB input?

What resistors are you using now? When I used the recommended 330ohm on the hot line in and a 75 ohm to ground i'd have to turn both contrast and brightness all the way down to get a decent brightness level and it still didn't look right. Switched to 100ohm to ground and i'm right in the middle of both settings and the picture looks really good.
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matt
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Re: TV RGB mod thread

Post by matt »

golden potato wrote:The next set I’ll do is a KV-27V42. It has an unused RGB input on its jungle IC. As another commenter mentioned in this thread, it’s jungle IC data sheet is unavailable to determine if it’s an analog or digital RGB input, so I’m just going to try it and find out. Unfortunately, its AV switcher IC isn’t controlled via binary control signals but instead the more common serial control (I2C). I think for this TV I’ll try to setup a small microcontroller to sniff the I2C bus and bring the RGB blanking signal high when it detects that the AV switcher IC was told to switch to whatever input I commandeer for sync input (probably the SVIDEO input). However it would be nice to preserve the use of the SVIDEO input, so maybe I’ll throw a physical switch on the back to disable it so SVIDEO works like stock.
The second RGB input is indeed analog. The jungle chip used is mostly the same as a CXA2061 used in earlier models, which does have a datasheet available.

However, it's disabled by the I2C bus and isn't normally accessible. Another user here has started working on a method to unlock it, though:

viewtopic.php?f=6&t=68917
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matt
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Re: TV RGB mod thread

Post by matt »

DemoNight wrote:
matt wrote: For my Trinitron mods, I've been using 820 ohms inline and 75 to ground. This works for me.

The S-Video jack on your TV will have a pin that's grounded when you plug in an S-Video cable. You'll be able to see which one it is, since it will touch the outer shield of the S-Video plug when it's connected. Figure out which one it is with a multimeter, and wire it up in tandem with the blanking switch.
That seems like a lot of resistance, does the resistance on the inline side just do less than when you put resistors to ground? With my 150ohm to ground and 330 ohm inline the picture is a touch to dark.
The inline resistors are used to balance the voltage level of the OSD signal so that it has the proper brightness level when mixed. They don't affect the brightness of the external RGB signal very much.

This only works if the inline resistor is placed after the 75 ohm terminating resistor. Otherwise it will darken the picture.
DemoNight
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Re: TV RGB mod thread

Post by DemoNight »

matt wrote:
DemoNight wrote:
matt wrote: For my Trinitron mods, I've been using 820 ohms inline and 75 to ground. This works for me.

The S-Video jack on your TV will have a pin that's grounded when you plug in an S-Video cable. You'll be able to see which one it is, since it will touch the outer shield of the S-Video plug when it's connected. Figure out which one it is with a multimeter, and wire it up in tandem with the blanking switch.
That seems like a lot of resistance, does the resistance on the inline side just do less than when you put resistors to ground? With my 150ohm to ground and 330 ohm inline the picture is a touch to dark.
The inline resistors are used to balance the voltage level of the OSD signal so that it has the proper brightness level when mixed. They don't affect the brightness of the external RGB signal very much.

This only works if the inline resistor is placed after the 75 ohm terminating resistor. Otherwise it will darken the picture.

Just to be clear, the terminating resistor is the resistor that is to ground, correct? And in your case the 820ohm resistor is on the RGB lines as they go to the CRTs circuit board, do I have that right? If that's the case ill go mess around more on my bread board to see if 75ohm to ground and 820 on the hot in looks right.
camtron47
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Re: TV RGB mod thread

Post by camtron47 »

DemoNight wrote:
camtron47 wrote:
camtron47 wrote:So I did the OSD mux mod on my BG-3S chassis and it worked properly for about 5 minutes and then everything turned purple due to losing green input. The OSD is purple too (even on composite input).
I've done a quick check of the green circuit and it doesn't seem to be grounded inappropriately anywhere. So all I can think of is the 100nF capacitor I put in went bad (seems unlikely?) or the green input on the jungle got fried. Is that possible?
Has anyone seen this happen before?
Thanks
I fixed my purple problem. It was either the green input capacitor was dodgy or more likely I'd soldered it on poorly because by replacing it with a fresh cap and double checking the joints, it all looked good and now I've got full colour again.
Next thing I've noticed is that the picture is slightly but noticeably washed out when switching to RGB. When turning on the blanking switch a black background visibly turned a bluish grey for example. Is this common? Do I need more input resistance as mention in recent posts? Or am I fine to just recalibrate the brightness to better suit the RGB input?

What resistors are you using now? When I used the recommended 330ohm on the hot line in and a 75 ohm to ground i'd have to turn both contrast and brightness all the way down to get a decent brightness level and it still didn't look right. Switched to 100ohm to ground and i'm right in the middle of both settings and the picture looks really good.
I'm using 75 ohms to ground followed by 390 ohms in line. I chose 390 based off the chart as I have 2.2kohm inline OSD resistors and I've also included the diodes. There's also some caps in parallel with the 2.2k resistors, not sure what effect those have. My post on the previous page has a drawing of my input circuit before and after.

Perhaps I'll try 100 ohm termination as see if that's an improvement. Can you point me to any other examples of mods done with 100 ohms instead of 75? I'm curious as to why this could be need, it seems like an odd case.
DemoNight
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Re: TV RGB mod thread

Post by DemoNight »

matt wrote:
DemoNight wrote:
matt wrote: For my Trinitron mods, I've been using 820 ohms inline and 75 to ground. This works for me.

The S-Video jack on your TV will have a pin that's grounded when you plug in an S-Video cable. You'll be able to see which one it is, since it will touch the outer shield of the S-Video plug when it's connected. Figure out which one it is with a multimeter, and wire it up in tandem with the blanking switch.
That seems like a lot of resistance, does the resistance on the inline side just do less than when you put resistors to ground? With my 150ohm to ground and 330 ohm inline the picture is a touch to dark.
The inline resistors are used to balance the voltage level of the OSD signal so that it has the proper brightness level when mixed. They don't affect the brightness of the external RGB signal very much.

This only works if the inline resistor is placed after the 75 ohm terminating resistor. Otherwise it will darken the picture.
Just tried the 75/820 combo and that just might be the magic bullet for my set. It looks GREAT. Gonna play some more SNES games just to make sure then move onto getting my sync and sense circuits setup properly, then audio hook ups. Then i'm ready to button her up and game away!
camtron47 wrote:
I'm using 75 ohms to ground followed by 390 ohms in line. I chose 390 based off the chart as I have 2.2kohm inline OSD resistors and I've also included the diodes. There's also some caps in parallel with the 2.2k resistors, not sure what effect those have. My post on the previous page has a drawing of my input circuit before and after.

Perhaps I'll try 100 ohm termination as see if that's an improvement. Can you point me to any other examples of mods done with 100 ohms instead of 75? I'm curious as to why this could be need, it seems like an odd case.

Your gonna have to look around, I know I read it in this thread a few times, something to do with Sony sets. Though, I just tired what the other guy recommended. 75ohm to ground with 820ohm on the hot side. Looks just about perfect. Gonna be honest I don't have a clue what i'm doing. I'm just trying stuff on my bread board till it looks right to me. I put up the display adjust in RE2 setting and with the 75/820 combo with Picture and Brightness at a little less than half it looks perfect.
RogerB
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Re: TV RGB mod thread

Post by RogerB »

Okay I finally figured and performed the RGB mod on the Sharp 20KS100. I realized that the resistor I need to tap to for the mod was in the backside of the board they were surface mounted resistors. So what I did was remove those resistors and since the 100 nano farad capacitor were through hole I connect my through hole resistor but I used pref board to have easy access of the RGB input since it was in the other side of the board. What I used on the pref board was 1100 ohm resistor with a 75 ohm resistor to ground. Now it's technically working but I have two problems now. For some reason the colors are like in a purple tint and when I switch to RGB mode I get some noise and with the purple color. I have the switch for the blank signal properly placed.

Please I need help because I honestly don't know what to do at this point I tried everything. But still I get purple color in the video input and there's noise when I turn on the RGB mode. I don't know if has to do with the scart cable I am using. But the same time I used regular composite and now even that is purple.

Here's a picture of it
https://drive.google.com/file/d/1qHDRSn ... p=drivesdk

I would really appreciate if anyone has any ideas on what it could be .
Here's the service manual for my Television: https://diagramas.diagramasde.com/otros ... 0KS100.pdf
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

RogerB wrote:Okay I finally figured and performed the RGB mod on the Sharp 20KS100. I realized that the resistor I need to tap to for the mod was in the backside of the board they were surface mounted resistors. So what I did was remove those resistors and since the 100 nano farad capacitor were through hole I connect my through hole resistor but I used pref board to have easy access of the RGB input since it was in the other side of the board. What I used on the pref board was 1100 ohm resistor with a 75 ohm resistor to ground. Now it's technically working but I have two problems now. For some reason the colors are like in a purple tint and when I switch to RGB mode I get some noise and with the purple color. I have the switch for the blank signal properly placed.

Please I need help because I honestly don't know what to do at this point I tried everything. But still I get purple color in the video input and there's noise when I turn on the RGB mode. I don't know if has to do with the scart cable I am using. But the same time I used regular composite and now even that is purple.

Here's a picture of it
https://drive.google.com/file/d/1qHDRSn ... p=drivesdk

I would really appreciate if anyone has any ideas on what it could be .
Here's the service manual for my Television: https://diagramas.diagramasde.com/otros ... 0KS100.pdf
The link to your picture isn't working.

If I had to guess why your picture is purple regardless of your input, it's possible that your 1100 ohm resistors aren't providing enough resistance for the Micom to function properly. I've had a similar problem with one of my TVs when I replaced my OSD grounding resistors with the mux resistors from the In-line resistor table. In my case, the TV would turn off after a few seconds on a blank screen due to the Micom over-powering the CRT from a lack of proper resistance, but when I had my console plugged into it, the screen was tinted purple. What I ended up doing was combining resistors that are of the same specification of the original OSD grounding resistors with my mux resistors to fix the issue.

Since the original OSD grounding resistors are 1800 ohm in your case (which I'm guessing are the surface mount resistors you removed), try adding 1800 ohm resistors in series with your 1100 ohm mux resistors to see if it fixes your problem.
RogerB
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Joined: Thu Jun 24, 2021 1:28 am

Re: TV RGB mod thread

Post by RogerB »

KPackratt2k wrote:
RogerB wrote:Okay I finally figured and performed the RGB mod on the Sharp 20KS100. I realized that the resistor I need to tap to for the mod was in the backside of the board they were surface mounted resistors. So what I did was remove those resistors and since the 100 nano farad capacitor were through hole I connect my through hole resistor but I used pref board to have easy access of the RGB input since it was in the other side of the board. What I used on the pref board was 1100 ohm resistor with a 75 ohm resistor to ground. Now it's technically working but I have two problems now. For some reason the colors are like in a purple tint and when I switch to RGB mode I get some noise and with the purple color. I have the switch for the blank signal properly placed.

Please I need help because I honestly don't know what to do at this point I tried everything. But still I get purple color in the video input and there's noise when I turn on the RGB mode. I don't know if has to do with the scart cable I am using. But the same time I used regular composite and now even that is purple.

Here's a picture of it
https://drive.google.com/file/d/1qHDRSn ... p=drivesdk

I would really appreciate if anyone has any ideas on what it could be .
Here's the service manual for my Television: https://diagramas.diagramasde.com/otros ... 0KS100.pdf
The link to your picture isn't working.

If I had to guess why your picture is purple regardless of your input, it's possible that your 1100 ohm resistors aren't providing enough resistance for the Micom to function properly. I've had a similar problem with one of my TVs when I replaced my OSD grounding resistors with the mux resistors from the In-line resistor table. In my case, the TV would turn off after a few seconds on a blank screen due to the Micom over-powering the CRT from a lack of proper resistance, but when I had my console plugged into it, the screen was tinted purple. What I ended up doing was combining resistors that are of the same specification of the original OSD grounding resistors with my mux resistors to fix the issue.

Since the original OSD grounding resistors are 1800 ohm in your case (which I'm guessing are the surface mount resistors you removed), try adding 1800 ohm resistors in series with your 1100 ohm mux resistors to see if it fixes your problem.

Okay than I will change the resistors back a 1800 ohm resistor plus 1100 ohm with 75 ohm resistor to ground. I'm just worried about the voltage output though, because if you do the voltage divider formula you get 1.5 volts output you get since 5×(1800+1100+75/(6800)+(1800+1100+75))=1.52 v. I just want to make sure that's safe to do because I don't want to end frying my tv IC or anything like that. I will still test it though.

By the way here's a working link to the to my image
https://imgur.com/gallery/7aPnzmx


Update: still didn't work after doing what you said, it's still purple but much brighter
IsraelMC
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Joined: Sun Aug 22, 2021 3:18 pm

Re: TV RGB mod thread

Post by IsraelMC »

Buenas tardes, disculpe mi ingles estoy usando un traductor..
soy nuevo en este foro, ando buscando ayuda, estoy haciendo un mod a un TV sony KV-27V10 Chasis AA-1
Hasta los momentos lo que hecho es retirar el Closed Caption de la placa e inyectar el rgb directo al chip CXA1465AS
el YS levanta a partir de 1v, en las lineas RGB solo he puesto una resistencia de 75ohm a tierra y un condensador de 0.1uf
y la sincronia la obtengo por video compuesto, el problema esta enque los colores se me ven muy oscuros y el blanco de se ve gris. alguna recomendacion
Aqui les dejo imagenes de como se ve:


Estoy intentando usar una pc con los emudriver para emitir a 15 khz.
Gracias!!!

https://imgur.com/b2JO8pl
https://imgur.com/wdgvwV0


Good afternoon, excuse me my English I am using a translator ..
I'm new to this forum, I'm looking for help, I'm making a mod to a Sony KV-27V10 TV Chassis AA-1
So far what I have done is remove the Closed Caption from the board and inject the rgb directly to the CXA1465AS chip
the YS lifts from 1v, in the RGB lines I have only put a 75ohm resistor to ground and a 0.1uf capacitor
And I get the synchrony by composite video, the problem is that the colors look very dark and the white looks gray. Any recommendation
Here I leave you images of how it looks:



I am trying to use a pc with the emudriver to broadcast at 15 khz.
Thanks !!!
Virtual Davey
Posts: 9
Joined: Tue Jun 23, 2020 5:45 am

Re: TV RGB mod thread

Post by Virtual Davey »

I successfully RGB modded my set awhile back (GXTV). The picture is beautiful when in RGB, but if I use composite or RF, there is too much red in the picture. I entered the sub menu but don't see any adjustment for lowering the red. Below is a picture of my settings from the manual. the settings under the "Initialized MICOM Data" is the value of my settings at this time (which happens to be perfect for RGB).
I figured the "Red cut off adjustment" would be what I needed to adjust, but it's already set as low as it could go, which is "0". I'm guessing that I would have to raise both the Green & Blue cut off to compensate? Would that even work? This might adversely affect my RGB picture I would think.

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lBleter
Posts: 1
Joined: Thu Aug 26, 2021 3:49 am

Re: TV RGB mod thread

Post by lBleter »

Hi all, I was wondering if it would be possible to component mod my mini 6" crt radio. I can't rgb mod it, not even directly into the neckboard because the main ic has pin 24 R-y and pin 25 B-y inputs. But my idea is to tap into them, and use pin 5 to use luma as sync and pin 14 as ground. Please see links.
Schematic pages 49 and 50
https://drive.google.com/file/d/1YUScJS ... sp=sharing
uPC1365C
https://drive.google.com/file/d/1C7igS4 ... sp=sharing
IsraelMC
Posts: 2
Joined: Sun Aug 22, 2021 3:18 pm

Re: TV RGB mod thread

Post by IsraelMC »

Buenas tardes, disculpe mi ingles estoy usando un traductor..
soy nuevo en este foro, ando buscando ayuda, estoy haciendo un mod a un TV sony KV-27V10 Chasis AA-1
Hasta los momentos lo que hecho es retirar el Closed Caption de la placa e inyectar el rgb directo al chip CXA1465AS
el YS levanta a partir de 1v, en las lineas RGB solo he puesto una resistencia de 75ohm a tierra y un condensador de 0.1uf
y la sincronia la obtengo por video compuesto, el problema esta enque los colores se me ven muy oscuros y el blanco de se ve gris. alguna recomendacion
Aqui les dejo imagenes de como se ve:


Estoy intentando usar una pc con los emudriver para emitir a 15 khz.
Gracias!!!

https://imgur.com/b2JO8pl
https://imgur.com/wdgvwV0


Good afternoon, excuse me my English I am using a translator ..
I'm new to this forum, I'm looking for help, I'm making a mod to a Sony KV-27V10 TV Chassis AA-1
So far what I have done is remove the Closed Caption from the board and inject the rgb directly to the CXA1465AS chip
the YS lifts from 1v, in the RGB lines I have only put a 75ohm resistor to ground and a 0.1uf capacitor
And I get the synchrony by composite video, the problem is that the colors look very dark and the white looks gray. Any recommendation
Here I leave you images of how it looks:



I am trying to use a pc with the emudriver to broadcast at 15 khz.
Thanks !!!
patricksouza472
Posts: 1
Joined: Fri Sep 03, 2021 3:55 am

Re: TV RGB mod thread

Post by patricksouza472 »

Hello there, I'm from Brazil and I'm trying to mod my first CRT TV for use with CRT Emudriver. It's a LG Cinemaster CP-29K30 with MC-005A chassis, and it uses the Toshiba IC TB1251CN. I have downloaded the service manual for this board (which is actually just a schematic) and it looks like there's no inline caps or 75 ohm resistors to ground BUT it has Ext. RGB lines (pins 16, 17, 18), Ys (pin 15) and a line called "RGB Vcc (9V)" (pin 14) What would be the best way to RGB mod this set?
User avatar
Osirus
Posts: 214
Joined: Tue Jun 16, 2020 8:51 pm

Re: TV RGB mod thread

Post by Osirus »

IsraelMC wrote:Buenas tardes, disculpe mi ingles estoy usando un traductor..
soy nuevo en este foro, ando buscando ayuda, estoy haciendo un mod a un TV sony KV-27V10 Chasis AA-1
Hasta los momentos lo que hecho es retirar el Closed Caption de la placa e inyectar el rgb directo al chip CXA1465AS
el YS levanta a partir de 1v, en las lineas RGB solo he puesto una resistencia de 75ohm a tierra y un condensador de 0.1uf
y la sincronia la obtengo por video compuesto, el problema esta enque los colores se me ven muy oscuros y el blanco de se ve gris. alguna recomendacion
Aqui les dejo imagenes de como se ve:


Estoy intentando usar una pc con los emudriver para emitir a 15 khz.
Gracias!!!

https://imgur.com/b2JO8pl
https://imgur.com/wdgvwV0


Good afternoon, excuse me my English I am using a translator ..
I'm new to this forum, I'm looking for help, I'm making a mod to a Sony KV-27V10 TV Chassis AA-1
So far what I have done is remove the Closed Caption from the board and inject the rgb directly to the CXA1465AS chip
the YS lifts from 1v, in the RGB lines I have only put a 75ohm resistor to ground and a 0.1uf capacitor
And I get the synchrony by composite video, the problem is that the colors look very dark and the white looks gray. Any recommendation
Here I leave you images of how it looks:



I am trying to use a pc with the emudriver to broadcast at 15 khz.
Thanks !!!
I've modded this same chip with good results. Maybe try a bit higher blanking voltage. IIRC 1v is the absolute minimum. Also double check your 75 ohm terminations, make sure there isn't another termination somewhere in parallel that's lowering the input impedence.
j4ck3t
Posts: 1
Joined: Tue Sep 14, 2021 7:23 pm

Re: TV RGB mod thread

Post by j4ck3t »

Hi sorry to bother you, please excuse my English, I'm trying to save my grandma old tv from the dumpster, i have a very basic understanding of electronics but this thread gave me the courage to go for it.
I'm still in the middle of disassembly because some of the connectors are stuck but i can already foresee a bunch of problems.
The OSD chip doesn't seem to have any resistors attached to it, but it has inductors according to the diagram which i can see on the board (they are a different color than resistors), so i have no idea how to calculate the new resistors for the mix method.

Here's the schematic for the chassis and the datasheet for the chip.
https://elektrotanya.com/philco_14av49_ ... nload.html
https://html.alldatasheet.com/html-pdf/ ... 04PSC.html

Any help is greatly appreciated, thanks in advance.
snappleman
Posts: 15
Joined: Tue Aug 22, 2017 9:05 pm

Re: TV RGB mod thread

Post by snappleman »

So I found a KV-20S40 (BA-4 chassis) and the noticed OSDmux mod looked very straightforward on it/ I modded it and as far as I know I did it correctly but I can't get things working. RGB blanking only makes the screen darker and still shows the composite video signal.

I saw MarkOZLAD had a guide on a very similar chassis (BA-4D) which is almost the same aside from differently numbered resistors, and it was basically the same thing I did, the only difference was he added diodes, which I ended up doing just because, and changing my resistor values to match, but everything else is the same. The darkening of the screen is the same as when the menu is bought up and the picture gets dimmed. I tried an RGB source without composite video on the sync, that showed no picture at all.

I also tried wiring the sync to both the composite video input and the (unpopulated but still properly terminated) s-video pad, same result. The 5V I'm getting from the tuner since it's a closer and stronger connection, so I don't know if that's an issue. I checked the blanking voltage coming from the OSD, it's 0.5v. With the voltage divider built into the switch I put together I get 2.5v, but I also played around a bit and tried 0.3-5v just to test. At lower voltages it doesn't blank, the threshold seems to be 0.5v but the more voltage I use the darker the screen becomes when the switch is engaged, and even then no RGB, just composite.

Anyway I'm sure I overlooked something but right now I have no idea what, any suggestions?
snappleman
Posts: 15
Joined: Tue Aug 22, 2017 9:05 pm

Re: TV RGB mod thread

Post by snappleman »

ughhh.... I accidentally wired my RGB inputs on the SCART connector one pin over... fixed and working perfectly now... :|
payitaht_
Posts: 1
Joined: Fri Oct 08, 2021 5:37 am

Re: TV RGB mod thread

Post by payitaht_ »

Hi guys, I want add RGB Scart to my AG-3E chassis Sony KV-DR34M69 EDTV.
İs that tv can RGB moddable?

Thanks.
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