TV RGB mod thread

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sparker599
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Re: TV RGB mod thread

Post by sparker599 »

sparker599 wrote:
GeneraLight wrote:There's an RGB modded KV-27FV300 for $80 in Burnaby, BC
https://vancouver.craigslist.ca/bnc/ele ... 88155.html
This is my TV. I posted about it here: viewtopic.php?f=6&t=56155&p=1300227#p1300227 See that page for any pics and diagrams related to this particular tv.

I am holding off on selling it because I see this weird moving bands up and down on the screen when using these RGB inputs, but only noticeable on solid blocks of medium or dark shades or colors, not bright shades or colors or areas with more detail, see either of these videos
. It looks worse than I remember it looking a few months ago. See either of these videos that I just took:
https://drive.google.com/open?id=1TkhN7 ... wf5DcukGFt

A friend recommended I upgrade to coax wiring and plugs, but this was all I could find for wiring https://www.digikey.com/catalog/en/part ... able/42223 I'm not even sure if i'm looking at the right stuff on digikey. Where do you guys get coax cabling for RGB mods? Do you even use coax cabling at all?
I do have a SNES composite cable that I was considering cutting into pieces and using this cable as my RGB lines to go from the BNCs to the OSD. The cable's console end had already been cut off by a friend using it for another project.
If anyone else can give me some advice about this banding issue, I would really appreciate it.

I've greatly reduced the amount of interference. It's now only visible when a large dark area is displayed on the screen. I don't know why, but there is interference on all video inputs, not just RGB.
There are 2 groups of wires that connect the mainboard to the neck board. Twisting these together to move them farther away from the flyback, like they were when I first picked up the TV, helped to reduce the interference. Also helpful was twisting ground wires around the RGB wires to make twisted pairs. I left the red and blue ground wires disconnected because having those connected actaully increased the amount of interference compared to just having the green one connected.

Twisted pairs for RGB wires
Image

The two groups of wires twisted together
Image

MarkOZLAD wrote:Just wanted to make a quick note about the OSD RGB Mux method.

When implemented the OSD and External RGB signals are essentially being put through an "Max" function. This means that the signal will show the maximum of either the OSD RGB or the External RGB. In practice this means that the OSD will not show well on bright screens. This is because the external RGB is already maxed out and the OSD RGB can't be any brighter.
I changed the RGB inline resistors to 750 ohms and now the brightness on RGB is the same as component, and also the OSD is much more readable on bright screens than it was at 470 ohms. I compared Super Mario World and Sonic 1 on Wii VC (component video) to the same games running on my 2chip SNES and genesis 2 (RGB scart with a VGA adapter that I made).

Volume only
Image

Full OSD
Image

OSD on white screen (not sure why a purple patch appears on the left side. I don't see it in person.)
Image

MarkOZLAD wrote: Excuse the crudeness of my edits but I think this would be better for the RGB circuits.

Image
I read your other post here viewtopic.php?f=6&t=56155&p=1296533#p1296533
but I still don't understand the reason why or how this would be better. Does it have something to do with some consoles having 75ohm termination and some not?
I'm willing to try it for my next mod, but the image looks perfectly fine to me on both of the TVs that I modded, and both already had 680 ohm termination resistors already installed for the OSD. I know that 75 ohm termination resistors are for preventing ghosting, but I never had that with my consoles or PC on my TVs.
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Re: TV RGB mod thread

Post by MarkOZLAD »

sparker599 wrote: but I still don't understand the reason why or how this would be better.
I drew up the circuit because if you implemented it you would have correctly terminated external RGB at 75 ohms and also have the OSD RGB at the correct peak to peak voltage to mux with the external RGB.
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Mikeyy00
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Re: TV RGB mod thread

Post by Mikeyy00 »

BobWoggle wrote:First things first, check whether that black screen is a blanked screen. Try plugging in and switching to another A/V input, with your scart plugged in and driving that pin.

It does go black on all inputs.. so I guess the blanking is working.

I'll hold off until I get a new set of caps, and a proper scart plug.
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cyborc
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Re: TV RGB mod thread

Post by cyborc »

sparker599 wrote: I've greatly reduced the amount of interference. It's now only visible when a large dark area is displayed on the screen. I don't know why, but there is interference on all video inputs, not just RGB.
There are 2 groups of wires that connect the mainboard to the neck board. Twisting these together to move them farther away from the flyback, like they were when I first picked up the TV, helped to reduce the interference. Also helpful was twisting ground wires around the RGB wires to make twisted pairs. I left the red and blue ground wires disconnected because having those connected actaully increased the amount of interference compared to just having the green one connected.
Did you notice any interference before the TV was modded? I've had a few wega TVs in the past that exhibited interference patterns, and from what I've read online this can be caused by the tilt IC. Does the interference pattern change when you adjust the tilt function in the menu? (assuming this model has that)
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FinalBaton
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Re: TV RGB mod thread

Post by FinalBaton »

Very nice that the Sony FV300 has a documented mod now!

Also looking forward to seeing the Sony TS30 being rgb-modded. That set apparently has a really nice tube(same as lower tier PVMs of the time) and picture quality, and I've personally wanted one for a while
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XYXZYZ
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Re: TV RGB mod thread

Post by XYXZYZ »

I'm trying to mod an old Daewoo NTSC TV. I'm using a Raspberry pi with a video encoder called a "RetroTINK" that offers component and RGB through a VGA connector (for PVMs or projectors). There is also a composite option with an NTSC encoder, but I didn't get that one.

I have a 1V Csync signal going into the TV's composite input (the only option) and I get a picture, but it is rolling and jumping around erratically. Before I go into detail about the mod, could this be because I don't have an NTSC encoder? I saw 2skoops' post in this thread about the pi, and someone suggested the pi doesn't output an NTSC sync signal. Since I don't have the NTSC encoder chip, perhaps this is why my picture is jumping around?

Here's some information about the RetroTINK - www.retrotink.com

Thanks
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BobWoggle
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Re: TV RGB mod thread

Post by BobWoggle »

Mikeyy00 wrote: It does go black on all inputs.. so I guess the blanking is working.

I'll hold off until I get a new set of caps, and a proper scart plug.
Alright, I'm thinking it is just that this jungle expects polarized electrolytic caps. another thing I for sure should've mentioned but slipped my mind is that both installs I've done on these have just disconnected the CCD lines further upstream and plugged terminated signals in the factory caps.
:^)
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Re: TV RGB mod thread

Post by MarkOZLAD »

XYXZYZ wrote:I'm trying to mod an old Daewoo NTSC TV. I'm using a Raspberry pi with a video encoder called a "RetroTINK" that offers component and RGB through a VGA connector (for PVMs or projectors). There is also a composite option with an NTSC encoder, but I didn't get that one.

I have a 1V Csync signal going into the TV's composite input (the only option) and I get a picture, but it is rolling and jumping around erratically. Before I go into detail about the mod, could this be because I don't have an NTSC encoder? I saw 2skoops' post in this thread about the pi, and someone suggested the pi doesn't output an NTSC sync signal. Since I don't have the NTSC encoder chip, perhaps this is why my picture is jumping around?

Here's some information about the RetroTINK - http://www.retrotink.com

Thanks
Sounds more like a 50/60Hz thing to me. Would only need NTSC encoder when going through component. RGB doesn't need it.

Can you use SSH to change the Emulation Station to use a 60Hz setting?
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XYXZYZ
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Re: TV RGB mod thread

Post by XYXZYZ »

MarkOZLAD wrote:
XYXZYZ wrote:I'm trying to mod an old Daewoo NTSC TV. I'm using a Raspberry pi with a video encoder called a "RetroTINK" that offers component and RGB through a VGA connector (for PVMs or projectors). There is also a composite option with an NTSC encoder, but I didn't get that one.

I have a 1V Csync signal going into the TV's composite input (the only option) and I get a picture, but it is rolling and jumping around erratically. Before I go into detail about the mod, could this be because I don't have an NTSC encoder? I saw 2skoops' post in this thread about the pi, and someone suggested the pi doesn't output an NTSC sync signal. Since I don't have the NTSC encoder chip, perhaps this is why my picture is jumping around?

Here's some information about the RetroTINK - http://www.retrotink.com

Thanks
Sounds more like a 50/60Hz thing to me. Would only need NTSC encoder when going through component. RGB doesn't need it.

Can you use SSH to change the Emulation Station to use a 60Hz setting?
Okay, I fixed it. It turns out my connection from the Pi ground to the TV chassis ground had come loose.

So, it's finally working! It looks alright, not much better than composite video. The picture is way too bright, switching to the OSD and adjusting the settings has no effect at all. I can adjust the screen knob on the flyback and it looks less bright but the contrast looks bad. The focus knob is already in the best position. Maybe it's just a cheap TV with a worn out tube...

I'll post the details of my mod soon, maybe someone can give me some advice. Maybe I need different value caps or resistors.
Oh, and thanks for that suggestion about switching the frequency, I didn't think about that. Maybe that will come in handy.
XYXZYZ
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Re: TV RGB mod thread

Post by XYXZYZ »

Okay, here are the details if this Daewoo mod.

MODEL: Daewoo DTQ-19V1FC
CHASSIS - CN-001A
JUNGLE IC - DCT841B (Very similar to LA76845)
SERVICE MANUAL https://www.manual.guru/download-manual ... qHfMXzavyM

The source is a Raspberry Pi with a RetroTINK video encoder outputting 240x2048 RGB http://www.retrotink.com/

I added the RGB signal by removing one pin of the capacitors in the OSD lines and connecting the switch terminals to the caps. So far the picture is stable, but shifted slightly to the left, and too bright. The colors are alright. I can switch back to the OSD menu controls, but they don't have any effect on the RGB picture. The image is quite soft, not much better than a composite signal. I think maybe the tube is just low quality or worn out. Maybe it needs a recap?

Image
As you can see, the 75Ω in-line resistors and 0.1μF capacitors were already there! Lucky me. The composite in signal is also terminated with 75Ω.


The original OSD signal from the processor had 1KΩ series and termination resistors. These are bypassed, maybe that's why my image is so bright.
Image
So, I think I'll try adding some resistors to the RGB lines.
Last edited by XYXZYZ on Tue Mar 13, 2018 9:46 pm, edited 3 times in total.
XYXZYZ
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Re: TV RGB mod thread

Post by XYXZYZ »

I added some 1KΩ resistors in series between the source and the 4PDT switch. It didn't change the brightness.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

XYXZYZ wrote:I added some 1KΩ resistors in series between the source and the 4PDT switch. It didn't change the brightness.
Try adding 75 ohm resistors inline on the RGB lines before the termination resistors.
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XYXZYZ
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Re: TV RGB mod thread

Post by XYXZYZ »

Okay, I was wrong about those resistors on the RetroTINK. They were in series after all. So that meant there was no termination to ground on the RGB lines. I added 75Ω resistors to ground and now everything looks good! So, your suggestion was technically correct, I needed resistors in series and connecting to ground. Thanks!
Mikeyy00
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Re: TV RGB mod thread

Post by Mikeyy00 »

BobWoggle wrote:
Mikeyy00 wrote: It does go black on all inputs.. so I guess the blanking is working.

I'll hold off until I get a new set of caps, and a proper scart plug.
Alright, I'm thinking it is just that this jungle expects polarized electrolytic caps. another thing I for sure should've mentioned but slipped my mind is that both installs I've done on these have just disconnected the CCD lines further upstream and plugged terminated signals in the factory caps.

Well shit, maybe that was my issue all along. I think I tossed the original caps, but I'll double check the datasheet for what the values were.

Just to be clear, do you still use the 0.1uf caps and the 75ohm resistors, along with the existing caps? Or is it RGB Plug -> Original CAP -> Jungle?

Edit, looks like the original path from the CC chip is through three caps, one on each RGB line, and there's 3 1k resistors grounded. Wonder if I can just tap in there?
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BobWoggle
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Re: TV RGB mod thread

Post by BobWoggle »

Mikeyy00 wrote: Well shit, maybe that was my issue all along. I think I tossed the original caps, but I'll double check the datasheet for what the values were.

Just to be clear, do you still use the 0.1uf caps and the 75ohm resistors, along with the existing caps? Or is it RGB Plug -> Original CAP -> Jungle?

Edit, looks like the original path from the CC chip is through three caps, one on each RGB line, and there's 3 1k resistors grounded. Wonder if I can just tap in there?
For these I've just been going through the factory caps, no separate 0.1ufs. Still terminating to ground before the caps, though. Sorry for not being clear about that sooner, I went over what I was saying so many times in my head I forgot I hadn't already said it.
Last edited by BobWoggle on Sun Jul 01, 2018 8:32 pm, edited 1 time in total.
:^)
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cyborc
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Re: TV RGB mod thread

Post by cyborc »

The OSD mux method works great on a Sony KV-27S42. Now I just need to do a few tweaks to the geometry and white balance.

Thanks again Mark and Syntax!
Image
Image
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

cyborc wrote:The OSD mux method works great on a Sony KV-27S42. Now I just need to do a few tweaks to the geometry and white balance.

Thanks again Mark and Syntax!
Image
Image
What a beauty this is. Great OSD showing there. Makes me very happy to see this.
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Super happy to see another working mux in the wild.

Nice work! :)
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Apache Thunder
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Re: TV RGB mod thread

Post by Apache Thunder »

I'd like to give RGB modding a try for a couple TVs I own. I've gotten some soldering practice in with a few similar projects. Adding composite inputs to a couple old black and white TVs. :P

https://www.youtube.com/watch?v=lgxGIwGnjng
https://www.youtube.com/watch?v=qCF4j0Q3kqc

Those two vids are of adding Composite to a cheap 12 inch B&W. So it's kinda simple compared to what I'm wanting to do next. Got a bag full of 75 ohm resistors and I'm sure I got the needed caps laying around. Got the mobo from a TV I had to EoL a couple months back that has many of it's components recycled in my other TVs. (mainly the capacitors since I knew they were still good the last time the TV worked. CRT busted, so it wasn't an issue on the mobo that killed that TV)

I have a soft modded Wii and a Sega Genesis (model 2). Both of which I believe support RGB (with the Genesis having an external sync available. Not sure on the Wii yet). I'm not sure about the Wii though. It can do RGB yes? I may have to force that video mode/make the Wii think it's a PAL console perhaps. (it's a NTSC/USA region Wii). It is soft-modded (and an older model that supports BootMii on Boot2! :D ) But the Genesis is straight forward and found that it has native RGB support exposed to it's AV port. Once I'm ready to try this I'll get the cable/parts for the Genesis and the parts I would need for the TV. The Wii I'd attempt next if I got a working RGB mod. :P

The 2 color TVs I own:

Sanyo with 20inch CRT (model DS20424) - Unfortunately one of those "Flat" CRT tubes so has that usual distortion issue that's visible with side scrolling games involving the edges of the screen.
- Service Manual -

Philips with 27inch CRT (model 27PS50 B321 Chassis 7629) - This TV has an optional PIP module which is not present in my model. The connections for it appear to be there on the mobo. It might be using RGB for input but it may be component input though. Still new to reading schematics so not entirely sure on that. If tapping the PIP connections isn't an option there's either something related to ITV or I'd have to go the jungle IC route. (Jungle IC as in the connections to the neck board I assume?)

- Service Manual -

Both these TVs are somewhat modern. The Sanyo being made in 2004 and the Philips one being a couple years older being made in 2002.

Both TVs have OSD/Captions generated from the same IC that drives the whole board pretty much and aren't on separate chips unfortunately. OSD on both units appear to be muxed into the video feed withen the IC and isn't exposed on the PCB in a way that would be possible to tap into. :(

So what are my options with these? After checking over the 2 service manuals, which one is the best candidate? I would prefer to do the Philips. They both have component inputs but both TVs don't support 480p and can only do 480i off those inputs. The Sanyo seems to have some flicker (which doesn't bother me that much) with 480i compenent. Fast moving scenes like explosion fx in Skyward Sword on my Wii has flicker. It seems to be deinterlacing the video feed? Haven't noticed interlacing with it in the short time I used it. It has a tired flyback I think. I replaced all the main caps that the main video side of the PCB depends on and I still notice a noticable screen size change when bright objects appear on screen. (life meter in Skyward Sword moves noticably when I rotate camera from dark to bright areas. It's annoying and drove me to replace it with the 27inch Philips unit I have now.

But the Philips TV doesn't do any form of deinterlacing....So yeah I can notice the scanline separation thing when things move side to side on screen. That kinda of bugs me so this TV I'd want to RGB mod just so I can get around that. (it does handle 240p pretty well. NES looks great on it and after accessing the service menu on both tvs, the overscan settings are to my liking. :D )

I tried to get a Sony Trinitron but the one I found had a severe convergence issue where the corners were entirely unaligned with nearly a full inch of separation from R/G/B beams. I think the TV might have been dropped? Or the convergence strips (if it had any. Never bought that TV so didn't get the chance to take it apart. :P ) fell out/dislodged. That or the yoke became misaligned. Too bad, it's a Trinitron and was an older one too. Not one of those crappy flat CRTs that can have geometry issues as a result. It didn't have component inputs but being a Trinitron, it was definitly worth a serious RGB mod attempt. But the convergence was so bad I didn't want to risk putting $25 into something I might not be able to fix or would have to spend a lot more money getting parts for. :(

It was a 27incher and probably weighted in excess of 100+ pounds. Maybe a good thing I didn't get it and drop it attempting to bring it into the house. (and my crappy dresser seems to just barely handle holding up the Philips TV which is lighter then the Sony TV. :P )

So I guess I'm stuck with what I have. I live in a **tty town where there's nothing interesting here and since I can't drive I can't go any significant distance to a larger city to find a better TV. :( (and forget eBay. TVs in excess of 13+ inches become really expensive due to shipping. :( )

So what are my options for modding the Philips/Sanyo? I have some caps and resistors and basic soldering equipment. Though I'll need some additional stuff like cables/adapters (maybe some SCART related stuff to I guess?)

EDIT:

Also I have a Sony KV13TR24 coming soon. So for that one I plan to tap into the RGB connections the close captioning module uses (since this is an older TV that has that on a separate chip) The only question I have is how to deal with sync. There is no S-Video or connection anywhere where a clean sync signal goes. So I expect I need to use the composite video for that. So when getting a SCART cable for my console I should get one with a "Sync on Composite" connection correct? I think SCART has that as standard and cables with "clean sync" need active sync stripping circuitry to do that. Pretty sure sync strippers isn't something I need here since the TV I'm going to RGB mod isn't a PVM and doesn't have a dedicated sync line anywhere on the PCB that I can see. (Also I couldn't find the exact service manual for the KV13TR24. I could only find a KV13TR28 manual. Is that close enough? I won't know for sure till I open her up and compare the the CC module. But the only real difference I see between the two is a slight change in the chassis design to account for an extra pair of AV jacks it has)

The TV I am getting only has one pair of AV jacks on the rear of the TV. The 28 model seems to be the same feature wise with everything else. Probably even has the same method of service menu entry.

My plan is to expose the RGB connections from the CC module to a DB9 connector I will mount near the AV jacks on the back. Then build a box that will accept a SCART cable. Not sure if I should put in 75 OHM resistors + the caps or not. I noticed the Genesis model 2 cable I want to get already has those. I might add the caps and resistors and use jumpers to bypass them for cables that already have that stuff. Don't really want to put the resistors/caps on the connections inside the TV. Want to reduce the amount of work I do inside the TV. Might not even disconnect the lines from the CC module. Seems like as long as CC is disabled in the menu there wouldn't by any issues just bridging in my RGB port. Unless it's recommended I separate them? I there's enough pins on a DB9 connector that I could put them on seperate pins and setup a simple termination jack with the wires bridge over to "connect" the CC module to the RGB input when I'm not using the RGB box. :P

I'd rather not drill any more holes into the case then nessecery so I don't want to mount any additional switches. Just the DB9 port. :P
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Just found another consumer tv with csync problems.

Picture on a Samsung flat screen does a Mexican wave on csync, builds up and slows down.

Put comp video as sync rock solid picture.


J7st another reason to always use comp video as sync with consumer sets.
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Re: TV RGB mod thread

Post by MarkOZLAD »

Apache Thunder

The Sanyo's Jungle chip appears to be component only. See that a lot in late model Chinese sets. Not moddable by the means we normally discuss here, talk to the neckboard modders.

The Philips jungle MAY be able to be modded by injecting your RGB into the component ports or possible connector 0242. Sync in the AV port. 1-3V to blanking.
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Apache Thunder
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Re: TV RGB mod thread

Post by Apache Thunder »

Yeah looks like Sanyo isn't a pratical one to mod. As for the Philips...RGB into the Component ports? Interesting. Well Component is on "AV1" which shares a Composite Video jack. I suppose that would be where Sync on Composite would go. Maybe I'll try this.

As for the Sony KV-13TR24...Seems someone in a some random forum I found in google asked about if this tv had Closed Captioning and someone responded that it didn't....That means the service manual I found for the KV-13TR28 may have a significant difference. (though perhaps it has an unpopulated port for the CC module used by other versions of this TV? Initially I couldn't find the manual to my tv and the 13TR28 was the closest one. But I guess the TR27's manual seems to say that it's for TR24 as well)

First page of the service manual I found:

Image

Seems to indicate it's applicable to the KV13TR24 as well?


Here's a close up of the schematic of where I think I found usable RGB input:

Image

What is CP108? It doesn't seem to go anywhere. I can't tell if this is a unused port or if this is just a bunch of capacitors tied to ground or something. Still new to reading these schematics so I haven't learned all the symbols an what not. :P

This TV does have composite video so I think I can use that for sync.
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Re: TV RGB mod thread

Post by MarkOZLAD »

CP108 appears to be s block of six filter caps.

This TV is muxing the RGB from the OSD chip with the RGB output of the jungle. I don’t think it is a good candidate.
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Apache Thunder
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Re: TV RGB mod thread

Post by Apache Thunder »

Yeah that seems to be the case. I followed the lines to another chip and they interconnect with lines going to the neck board:

Image

The Blue connection simply terminates into that filter cap row you mentioned so it doesn't even bother muxing that one. So I can see why that area is not a suitable location for RGB.

Instead it looks like I have to input from where the final output originates.

Oh and here's the numbers those final RGB lines correspond to in the diagram. They seemed to include what voltage/signal characteristics they should have:

Image
(the circled numbers in the first image link over to this part of the schematic)

They seem to pass through 330ohm resistors before going out to the neckboard connector? I suppose I'd have to tap in just before those resistors. But then I may have to amplify the RGB lines to match what the chip was using. Then again not sure if the chip outputs standard RGB and it just gets amplified at the neckboard seeing that the chip's RGB goes through resistors before breaking out to the neckboard.


Oh and here's what the neckboard schematic looks like:

Image

EDIT:

Another thing I forgot to mention regarding the Philips TV. It seems to handle PAL formats over Component just fine. Used 240p test suite (the Wii version) and tested the various PAL modes. Pretty much all of them displayed correctly (seems to handle 288p too?) Though overscan settings would need to be adjusted for the PAL stuff. Interesting. I think maybe indeed it might accept RGB over Component. The only thing it doesn't do is any 480p stuff though so 15khz only it seems. (also tested this over composite video. Doesn't lose sync, but color information is lost when I use any of the PAL modes on Composite)

EDIT2: Lol tried the same over component on the Sanyo TV. It doesn't like PAL at all. Loses vertical sync on all the PAL modes. :P

EDIT3:

Ok yeah so TV always expects Component on the Component inputs. Jammed in some temp wires into the back of my genesis model 2 where the RGB lines are. This was the result:

Image

Seems to ignore the AV/S-Video Jacks when Component mode is active. And somehow this TV still manages to maintain sync? Since the other jacks are ignored I had only the RGB lines and nothing for sync coming in and somehow the darn thing still manages with what it has. :P

Anyways green channel is missing so yeah it seems to be in Component mode always. Maybe there's something in the service menu to change this but I doubt it. I wouldn't be surprised if the OSD/PIP lines are in component too...At this point if I'm going to tap the lines going to the neckboard I might as well do it on the Trinitron set I will soon have. That one only has composite so that one has something to gain. I'll just use the big Philips TV for my Wii. :P
Zektor
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Location: Minnesota

Re: TV RGB mod thread

Post by Zektor »

I would like to mod my Zenith A25A11D. I’ve been slowly making my way through this tread (up to page 14) but haven’t run across any mods for Zenith TV’s. I’m hopeful someone will let me know if this TV is a good candidate.
Here is a link to the TV Service Manual: (page 103 shows the IC)
https://www.manualslib.com/manual/88416 ... ct-A25A11D
Here is the link to the datasheet on the IC (TA1268N):
http://www.alldatasheet.com/datasheet-p ... 1268N.html

I think I have a pretty good understanding of what to do, but I still have a couple of questions.
It looks like the OSD RGB pins are 15, 16, 17, and the blanking pin is 14. Where I get confused is on the Vpp. I know it should be around 0.7 Vpp, but I’m not sure where to look for that information. I want to say it’s 1.0 Vpp, but I would want someone to verify that, or let me know where to find it. Also, if it really is 1.0 Vpp, how do I make that work?
The other questions involve the volts used for the blanking pin. I’ve heard 5V used a lot, but I’m unsure if that’s really what I should be using. I see 3.3V and 9.0V pin outs on the IC. What should I be using?

So hopefully someone can help point me in the right direction and let me know if my TV is worth the trouble to mod. And I apologize if this information is in the thread somewhere. I will eventually get to it.
Thank you.
MarkOZLAD
Posts: 1004
Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

Apache Thunder wrote:
Seems to ignore the AV/S-Video Jacks when Component mode is active. And somehow this TV still manages to maintain sync? Since the other jacks are ignored I had only the RGB lines and nothing for sync coming in and somehow the darn thing still manages with what it has. :P

Anyways green channel is missing so yeah it seems to be in Component mode always. Maybe there's something in the service menu to change this but I doubt it. I wouldn't be surprised if the OSD/PIP lines are in component too...At this point if I'm going to tap the lines going to the neckboard I might as well do it on the Trinitron set I will soon have. That one only has composite so that one has something to gain. I'll just use the big Philips TV for my Wii. :P

I said to have TV in AV1 mode (well, whatever composite input it has), not component mode. Sync through composite port, RGB though component ports PrYPb and trigger blanking using a pot. Still not guaranteeing it will work. RGB can be locked out in the Jungle registers.
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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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Apache Thunder
Posts: 19
Joined: Tue Mar 20, 2018 2:11 am

Re: TV RGB mod thread

Post by Apache Thunder »

There is no way to switch to AV1 mode or CVI mode seperately. It defaults to AV1 when navigated to from another input/channel and only switches to "CVI" mode when component is detected. They are grouped as the same input on the back panel and also the same input in the menu and aren't independent of each other in that respect. :(

In fact when I was trying to test RGB on these inputs and tried to use the composite input for sync the tv would sometimes switch to AV1 on it's own. It was getting a bit confused. Though this only happened when I didn't have a stable enough picture from the component inputs. Once I got the wires stable it would stay in "CVI" mode and not switch back to AV1.
Last edited by Apache Thunder on Tue Mar 27, 2018 5:22 am, edited 1 time in total.
MarkOZLAD
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Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

Apache Thunder wrote:There is no way to switch to AV1 mode or CVI mode manually. It defaults to AV1 and then switches to "CVI" mode when component is detected. They are grouped as the same input on the back panel and also the same input in the menu. :(
That is so unusual. no other inputs?
___________________________________________________
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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Apache Thunder
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Re: TV RGB mod thread

Post by Apache Thunder »

Well yeah but I would assume that wouldn't help me much. I tried a port from AV2 while using component...no effect. So sync would have to be fed either on the component jack it expects or bypassed to something on the PCB instead. It seems like it's not setup to detect RGB. It's labeled YUV on the page for the rear IO as well so...

And I bet like the Sanyo everything is component and is just labeled RGB in the service manual because maybe there was a PAL version of this TV. The component inputs accept pal format stuff just fine. Only the composite (and S-Video too I guess? Though I don't have S-Video cable for Wii so couldn't that that) didn't handle the pal modes.

EDIT: I haven't tried triggering blanking on the PCB. Though. Haven't really pulled this part aside from cleaning it. Not sure how I would do that either. At this point I'm more interested in modding the Sony KV-13TR23 I will soon be in posession of. Looks like may have to be a neckboard tap though judging from the service manuals I found. But couldn't find one specifically labeled for this TV. I should know once I have the back off which of the 2 manuals I found match this TV. Though pretty sure the KV-13TR27 manual I found which lists the TR24 as one using the same chassis so looking more like a neckboard job with this one.

Might have to make a thread on this and see if anyone who's gone this route has to say on the matter. This TV has only composite and no other inputs besides RF. So at least it would be worthwhile. I wouldn't bother neckboard modding the Philips or the Sanyo. I'd rather just find a RGB to Component converter and call it a day with those TVs at this point. :P

Also I was taking a closer look at the back of the tube for the Philips tv. It has like 5+ convergance strips in it and I bet some of them are starting to lose their magnetism or have been jostled. There's minor convergence flaws near the corners/edges. It's barely noticable though it's at the point where I'm wondering if it was like that out of the factory. :P

There's also a minor but noticable warp in the shadow mask near the bottom of the TV. I know it's the shadow mask/tube because the actual phosphor groups are following the warp and is not the result of the elrectron beam being moved. There isn't any convergence issues in this warp area either so looks it came out of the factory like that? :P

lol the more I stare at this TV the more tiny flaws I find. Maybe I should stop with this one and look more on the Sony I'm about to have. This Philips TV has thus far been more then good enough for 3D games like Wii I currently have plugged into it. The Sony one I plan to use for my NES and Genesis. My PC's second monitor output via HDMI to S-Video/Composite converter will also be connected to this TV. The B&W I just got will be moved up top and will be used for my 3 stooges tapes as well as anything else I deem appropriate to watch on it over the color TVs around it. :P
MarkOZLAD
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Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

Apache Thunder wrote:EDIT: I haven't tried triggering blanking on the PCB. Though. Haven't really pulled this part aside from cleaning it. Not sure how I would do that either.
No way RGB is going to work without blanking triggered. It will just stay in YUV mode.

Sync into AV2, RGB into Component ports, trigger blanking.
___________________________________________________
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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