Component Video mod for curved screen Sony Trinitrons

[Bard_the_Bowman]

Wondering if people here are doing the component mod in preference to an RGB mod, or only to sets that can't be RGB modded in general?

Multiple reasons I did this mod over RGB
1. My entire setup is Component so doing this means I don't need any transcoders

That's my main reason. I have not RGB-modded any of my old consoles, and don't intend to as I like to preserve their original graphical fidelity (or rather, lack thereof). That leaves my Xbox, Gamecube, Wii, PS2, all of which have component output. So an RGB mod would just require needless adapters.

Also, as others have pointed out, you can do both mods pretty easily and switch between them with an appropriate switch. I think that's pretty cool, but didn't end up doing it because I literally don't own anything that outputs RGB

[vol.2]

And yes, I think the component mod bypasses it too. Because I can only see the difference between VM off/on with a non-component input.

Interesting. I thought this was basically "off" if you put the "sharpness" setting in the middle, or wherever it stops accentuating lines. For example the "sharpness" pattern in 240p Test Suite you can use to toggle until the black lines basically go away, but it's not "fuzzy."

Are you saying that totally removing the sharpening circuit from the set will potentially give better results than just adjusting it to the point where it appears "neutral?"

[Bard_the_Bowman]

And yes, I think the component mod bypasses it too. Because I can only see the difference between VM off/on with a non-component input.

Interesting. I thought this was basically "off" if you put the "sharpness" setting in the middle, or wherever it stops accentuating lines. For example the "sharpness" pattern in 240p Test Suite you can use to toggle until the black lines basically go away, but it's not "fuzzy."

Are you saying that totally removing the sharpening circuit from the set will potentially give better results than just adjusting it to the point where it appears "neutral?"

So, this is with the big fat disclaimer that I am new to the topic, and could very easily be wrong, but I think the TV's sharpening setting and VM are not necessarily the same thing. Someone more knowledgeable than me could probably explain the difference in more detail (assuming I'm correct and there is a difference).

[vol.2]

I think the TV's sharpening setting and VM are not necessarily the same thing. Someone more knowledgeable than me could probably explain the difference in more detail (assuming I'm correct and there is a difference).

Thanks

It would great if someone here could expatiate on that. Also, I would be then curious to know if doing the RGB mod (display hack) also bypasses this VM sharpening.

[matt]

Thanks

It would great if someone here could expatiate on that. Also, I would be then curious to know if doing the RGB mod (display hack) also bypasses this VM sharpening.

On curved Trinitrons with a VM circuit, it's always on with no way to disable it in the menu.

On the 32" AA-2Ds and the BA-4/4Ds, it's easy to unplug. On the 35" ones you have to get creative since the wiring harness is shared with other stuff.

I'm pretty sure RGB bypasses it. Typically it's driven by the luma signal from the jungle chip, which is missing in RGB mode. But honestly, I've always just unplugged it first thing and didn't give it much thought afterwards!

[matt]

Did you have excessive brightness that had to be adjusted with settings, or did the 220ohm resistors eliminate this?

They would not reduce brightness. To do that, you have to create a voltage divider (ie one inline resistor followed by another resistor to ground). The easiest way to do that is to put it before the 75 ohm termination resistor.

[vol.2]

On curved Trinitrons with a VM circuit, it's always on with no way to disable it in the menu.

Thanks

Is it the same thing as "sharpness" on sets that have a sharpness adjustment (meaning that you can "tune" it out)?

I have a KV-27S42, like the OG RGB mod that Mike Moffet did. Do you know if those are effected?

[Bard_the_Bowman]

Did you have excessive brightness that had to be adjusted with settings, or did the 220ohm resistors eliminate this?

They would not reduce brightness. To do that, you have to create a voltage divider (ie one inline resistor followed by another resistor to ground). The easiest way to do that is to put it before the 75 ohm termination resistor.

When you say "before", you mean the 75 ohm termination resistor would be between the jungle chip and the voltage divider resistor? So would one way to do this be to make an RCA plug adapter that would go between the TV and my component cables?

[Bard_the_Bowman]

On the 35" ones you have to get creative since the wiring harness is shared with other stuff.

It's pretty easy I found. I literally just put a toggle switch on the "VM Out" wire (pin 1). In my mind I kept thinking "this seems too easy" but I tested it with 240p test suite on a Wii hooked up with composite, and it totally works with very visible results. VM turns on and off with the switch no problem.

Pics: https://imgur.com/gallery/Cf6ZL6T

[KPackratt2k]

Did you have excessive brightness that had to be adjusted with settings, or did the 220ohm resistors eliminate this?

I don't recall encountering excessive brightness on the four AA-2 chassis sets that I've modded for Component, then again it's been a while since the last time I worked on a set with this chassis.

FWIW there's an XBR set that uses a variation of the AA-2 chassis and has a YPbPr input - the KV-32XBR48. It uses the same CXA2025AS jungle chip as the AA-2D chassis sets and splits Luma to the S-Video path for the purpose of sync processing. Perhaps copying parts of its circuit could help improve YPbPr mods for the AA-2 sets that don't have it?

Here's its service manual for those interested:
https://elektrotanya.com/sony_kv_32xbr4 ... nload.html

[matt]

Thanks

Is it the same thing as "sharpness" on sets that have a sharpness adjustment (meaning that you can "tune" it out)?

I have a KV-27S42, like the OG RGB mod that Mike Moffet did. Do you know if those are effected?

No, "sharpness" is something else. It's also bypassed by component & RGB mods.

The 27S42 doesn't have a VM circuit. The 27V42 does, however.

I don't recall encountering excessive brightness on the four AA-2 chassis sets that I've modded for Component, then again it's been a while since the last time I worked on a set with this chassis.

FWIW there's an XBR set that uses a variation of the AA-2 chassis and has a YPbPr input - the KV-32XBR48. It uses the same CXA2025AS jungle chip as the AA-2D chassis sets and splits Luma to the S-Video path for the purpose of sync processing. Perhaps copying parts of its circuit could help improve YPbPr mods for the AA-2 sets that don't have it?

Here's its service manual for those interested:
https://elektrotanya.com/sony_kv_32xbr4 ... nload.html

I wouldn't call it "excessive", but it's definitely there. You'll notice it if you switch back and forth between composite and YPbPr.

The XBR48 is an interesting design - the jungle chip is the same but it shares the YUV input pins with the PIP circuit. As a consequence, there's a video switching IC that selects between the two and may be able to assist with clamping the signal properly. I don't know how they manage the sync issue, but since this is a Sony design they have the luxury of controlling the jungle chip in ways we can't. It would make the most sense to run the Y signal through the S-video input and set the chip to use the internal luma signal, but I'm not sure the I2C bus is fast enough to switch to external luma when blanking for the PIP image.

You could totally make a universal Sony mod chip by hijacking the I2C signal, and could essentially turn any late model curved Trinitron into a de facto XBR48. It's been done on a small scale, all it needs is somebody with the right skill level to implement it. I am not that person but I wish I was.

[vol.2]

No, "sharpness" is something else. It's also bypassed by component & RGB mods.

The 27S42 doesn't have a VM circuit. The 27V42 does, however.

Thanks Matt,

I noticed in your write-up on CRT Database, you mention the V42 has a "streaking" issue in RGB, which sounds bad. The solution you mention is to put it in Vivid mode and turn the picture down. I wonder if this would mess with the ability to color balance the set afterwards. I always color balance CRTs with HCFR. Also, You mention the problem as being for the V42 chassis, but the NOTE exists on the bottom of the Database page for the S42; does this mean that it's present in both models?

I have an S42, so if it's not effected that would be great to know

[Bard_the_Bowman]

You could totally make a universal Sony mod chip by hijacking the I2C signal, and could essentially turn any late model curved Trinitron into a de facto XBR48. It's been done on a small scale, all it needs is somebody with the right skill level to implement it. I am not that person but I wish I was.

You and me both. That sounds awesome but I wouldn't even know where to begin

Edit: What do you mean when you say its been done on a small scale?

Edit2: Btw I made a 36 ohm RCA adapter last night and it marginally helped with brightness and I think colors look less washed out. I'm gonna try making a stronger one tonight.

[matt]

No, "sharpness" is something else. It's also bypassed by component & RGB mods.

The 27S42 doesn't have a VM circuit. The 27V42 does, however.

Thanks Matt,

I noticed in your write-up on CRT Database, you mention the V42 has a "streaking" issue in RGB, which sounds bad. The solution you mention is to put it in Vivid mode and turn the picture down. I wonder if this would mess with the ability to color balance the set afterwards. I always color balance CRTs with HCFR. Also, You mention the problem as being for the V42 chassis, but the NOTE exists on the bottom of the Database page for the S42; does this mean that it's present in both models?

I have an S42, so if it's not effected that would be great to know

Andy added that part, he found it worked based on an RGB mod he did for the 27V42. I haven't tried it personally. IMO it's not a good setting for composite/Svideo so that method is best if you're exclusively using RGB.

My S42 (on which most of that page is based) does have minor streaking after bright objects but it's not bad enough for me to care. It was visible before the mod and you'll see it on most online screenshots of that model. We went over the circuit pretty carefully to see if there were any red flags and didn't find anything obvious. Given that Andy was able to minimize it via the user menu I think it's an artifact of the jungle chip's design.

Edit: What do you mean when you say its been done on a small scale?

Edit2: Btw I made a 36 ohm RCA adapter last night and it marginally helped with brightness and I think colors look less washed out. I'm gonna try making a stronger one tonight.

This is for an earlier XBR model and was successful in altering the !2C signal to enable the extra RGB input.

https://pcbjunkie.net/index.php/project ... e-modchip/

That specific method doesn't work on the BA-4D, but there was another user who did so succesfully with an Arduino. I believe he posted about it on this forum. His method had some bugs and wasn't developed fully, but there's no reason why it wouldn't work.

[Bard_the_Bowman]

That specific method doesn't work on the BA-4D, but there was another user who did so succesfully with an Arduino. I believe he posted about it on this forum. His method had some bugs and wasn't developed fully, but there's no reason why it wouldn't work.

That link is really interesting. I wish I had more time to look into it. I've got some very rudimentary PCB design experience and have some experience with Arduinos as well, and that actually sounds like a really fun project. I just wish I had more hours in the day because I have a very large backlog of actual IRL home projects I need to do, and I don't think my wife would be very happy if I put "design a CRT modchip" up at the front of the list

[matt]

That link is really interesting. I wish I had more time to look into it. I've got some very rudimentary PCB design experience and have some experience with Arduinos as well, and that actually sounds like a really fun project. I just wish I had more hours in the day because I have a very large backlog of actual IRL home projects I need to do, and I don't think my wife would be very happy if I put "design a CRT modchip" up at the front of the list

Here's the thread for the BA-4D attempt. The code is open source and is based on Martin Hejnfelt's I2C hacks for JVC monitors (also open source).

viewtopic.php?p=1478649

I'm sure your wife will understand once she sees how cool the TV looks.

[vol.2]

My S42 (on which most of that page is based) does have minor streaking after bright objects but it's not bad enough for me to care. It was visible before the mod and you'll see it on most online screenshots of that model. We went over the circuit pretty carefully to see if there were any red flags and didn't find anything obvious. Given that Andy was able to minimize it via the user menu I think it's an artifact of the jungle chip's design.

Aha. Thanks Matt.

It seems like streaking of that sort is sometimes an issue with cabling or routing on the PCB. Impedance problems can cause reflections which can lead to smearing and ghosting. Maybe that has something to do with it.

[Bard_the_Bowman]

So this is a bit off topic but I never noticed it till I was messing around with brightness doing this mod (don’t think mod caused it, just made me notice it). Thought someone might have a quick idea.

I have some weird lines on my screen that look like creases on a sheet. They are very exaggerated in the pic cause it’s a long exposure but it gives a good idea of what they look like.

Anybody have any clue what this is? It doesn’t look like any pictures of burn in that I’ve seen.

https://imgur.com/gallery/25SipBb

[KPackratt2k]

Does this happen on the stock inputs too or does it only happen on Component? If it only happens on Component, it might help to reduce the blanking voltage by putting a grounding resistor on the blanking line to create a voltage divider, that was a suggestion given to someone who had this line occur in an RGB mod.

[Bard_the_Bowman]

Does this happen on the stock inputs too or does it only happen on Component? If it only happens on Component, it might help to reduce the blanking voltage by putting a grounding resistor on the blanking line to create a voltage divider, that was a suggestion given to someone who had this line occur in an RGB mod.

It happens with both unfortunately. But I've done some more research and apparently the curved "jailbar" is an inherent defect with the AA-2D but can maybe be reduced with new capacitors on the B+ line on the power supply. And the vertical bar in the pic probably indicates similar issue and probably can be fixed.

So I'm going to consult the service manual and replace some caps.

[Ramzelle]

Did you bridge where C375 was or did you just leave it be?

Leave it be. You don't want any connection there.

So had some time today, sadly there was already no cap on C375 for the 35V36 Model. Is there any other in like cap that could be inline that's causing my decrease in brightness? (doesnt look like it to me but thought id confirm)

https://imgur.com/a/fslCePT

[matt]

It happens with both unfortunately. But I've done some more research and apparently the curved "jailbar" is an inherent defect with the AA-2D but can maybe be reduced with new capacitors on the B+ line on the power supply. And the vertical bar in the pic probably indicates similar issue and probably can be fixed.

So I'm going to consult the service manual and replace some caps.

The rippling jailbars on the left are typically caused by bad B+ filter caps. Sometimes in places you wouldn't expect.

That curved line shows up sometimes. I wish I knew what causes it but I've never seen a satisfactory answer. I don't think it's related to the B+ ripple.

[Bard_the_Bowman]

It happens with both unfortunately. But I've done some more research and apparently the curved "jailbar" is an inherent defect with the AA-2D but can maybe be reduced with new capacitors on the B+ line on the power supply. And the vertical bar in the pic probably indicates similar issue and probably can be fixed.

So I'm going to consult the service manual and replace some caps.

The rippling jailbars on the left are typically caused by bad B+ filter caps. Sometimes in places you wouldn't expect.

That curved line shows up sometimes. I wish I knew what causes it but I've never seen a satisfactory answer. I don't think it's related to the B+ ripple.

Thanks. Looks like there's only 13 electrolytic caps on the power supply so I'm just gonna shotgun recap all of them. Ordered new ones, lowest impedance highest ripple current ones I could find.

If that doesn't help I'll look at the service manual and think about doing a partial recap of the mainboard.

[Bard_the_Bowman]

Two of the main benefits of this mod vs the usual RGB mod are that the OSD is unaffected and, unlike RGB, you can change the color saturation via the user menu. You can even use the AXNT "red push" if you want (I actually like this feature).

I just noticed this part of the guide. I'm wondering if it's not applicable to AA-2D, because the saturation adjustment on my AA-2D does absolutely nothing when using component input. Do you think that's just a chassis difference Matt or am I missing something perhaps?

[Ramzelle]

I just noticed this part of the guide. I'm wondering if it's not applicable to AA-2D, because the saturation adjustment on my AA-2D does absolutely nothing when using component input. Do you think that's just a chassis difference Matt or am I missing something perhaps?

Can confirm on my set this is also the case, Saturation Hue and Sharpness are disabled both in user menu and service menu

[KPackratt2k]

I just noticed this part of the guide. I'm wondering if it's not applicable to AA-2D, because the saturation adjustment on my AA-2D does absolutely nothing when using component input. Do you think that's just a chassis difference Matt or am I missing something perhaps?

Can confirm on my set this is also the case, Saturation Hue and Sharpness are disabled both in user menu and service menu

This was indeed the case on the four AA-2D chassis sets that I've YPbPr modded (two KV-27V20s, a KV-27V25, and a KV-27S22). Color, Hue, and Sharpness controls had no effect on the YPbPr mod on those sets. On the BA-4(C/D) chassis, Color control works on YPbPr, but not Hue and Sharpness.

Regarding that XBR model with Component: My friend lent me his KV-32XBR48 to repair (it had horizontal collapse and the power supply failed - I won't go into deep detail here though to avoid derailing the thread). Once I got it working, I tested the Component input and found that those settings that normally have no effect on the YPbPr mods (Color and Sharpness) actually work here. Looking at the service manual, the Y signal goes through a chip (A TA1226 IC) for processing and it happens to handle sharpness control, I'm guessing that explains the Sharpness control having an effect on this set but not on the ones with mods done to them. As for Color controls working on the XBR and BA-4, but not the AA-2D, my hunch is that Sony updated the firmware on later sets to allow the color setting to be changed on the YPbPr input.

[Ramzelle]

So I did so more trouble shooting on my AA-2D tonight. I found that when I switched back to composite my colors and brightness came back and the Tube wasn't as worn as I thought it was. Re-Tuning the Screen for composite I found that the image was fairly crisp and not blurry and I believe a lot of my issues have been from trying to compensate for the loss of color and brightness in my Component mod. It sound like my version of the AA-2D is slightly different than Bowmans since I did not have a cap in the same spot as him but overall they should be fairly similar.

I am trying to figure what I should look for to try and trouble shoot all this brightness and color loss. would too many ohms on a resistor, or a diode or some cap be pulling voltage and causing my issues. I am obviously not formally trained in small electronics but if I have something to go on I could try to investigate further and maybe cut an unimportant trace or something along those lines.

[Bard_the_Bowman]

So I did so more trouble shooting on my AA-2D tonight. I found that when I switched back to composite my colors and brightness came back and the Tube wasn't as worn as I thought it was. Re-Tuning the Screen for composite I found that the image was fairly crisp and not blurry and I believe a lot of my issues have been from trying to compensate for the loss of color and brightness in my Component mod. It sound like my version of the AA-2D is slightly different than Bowmans since I did not have a cap in the same spot as him but overall they should be fairly similar.

I am trying to figure what I should look for to try and trouble shoot all this brightness and color loss. would too many ohms on a resistor, or a diode or some cap be pulling voltage and causing my issues. I am obviously not formally trained in small electronics but if I have something to go on I could try to investigate further and maybe cut an unimportant trace or something along those lines.

Do you have any photos of your mod, or at least of the jungle chip area on your board? I am very visual when it comes to these things and have a hard time conceptualizing things without seeing them

I would be curious to take a look so I could see if there's any other differences on your particular set.

Also, you had asked about my resistor voltage divider mod, but I don't think that'll help in this case if your issue is LOW brightness since my RCA resistor mod thing was to reduce brightness.

[Ramzelle]

Do you have any photos of your mod, or at least of the jungle chip area on your board? I am very visual when it comes to these things and have a hard time conceptualizing things without seeing them

I would be curious to take a look so I could see if there's any other differences on your particular set.

Also, you had asked about my resistor voltage divider mod, but I don't think that'll help in this case if your issue is LOW brightness since my RCA resistor mod thing was to reduce brightness.

https://imgur.com/gallery/aa-d2-mod-ynasnPk

Maybe I should reduce the resistor amount on the blue, does polarity of the resistor matter. would daisy chaining the termination resistors cause this? you'll see in the photos as well as the 2 resistors are opposite direction

The picture i took does not show the the YPrPB soldered onto the Jungle but rest assure the signals pass through the .01uf cermaic caps to go into the jungle.

Since I'm losing so much brightness could something on the (g-wire)sync to svideo be pulling to much power and killing the brightness?

[Bard_the_Bowman]

Do you have any photos of your mod, or at least of the jungle chip area on your board? I am very visual when it comes to these things and have a hard time conceptualizing things without seeing them

I would be curious to take a look so I could see if there's any other differences on your particular set.

Also, you had asked about my resistor voltage divider mod, but I don't think that'll help in this case if your issue is LOW brightness since my RCA resistor mod thing was to reduce brightness.

https://imgur.com/gallery/aa-d2-mod-ynasnPk

Maybe I should reduce the resistor amount on the blue, does polarity of the resistor matter. would daisy chaining the termination resistors cause this? you'll see in the photos as well as the 2 resistors are opposite direction

The picture i took does not show the the YPrPB soldered onto the Jungle but rest assure the signals pass through the .01uf cermaic caps to go into the jungle.

Since I'm losing so much brightness could something on the (g-wire)sync to svideo be pulling to much power and killing the brightness?

I might be missing something but I don't see a pic of the jungle chip area in that link?