TV RGB mod thread

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matt
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Re: TV RGB mod thread

Post by matt »

mccutheon wrote:I just spoke with a friend with a ps2 who has the multi AV output cables that include both composite and component, in addition to audio. I think for now I will leave my VGA and its sync combiner aside, and instead take the RGB lines I have soldered to my board, and connect them up to some panel mount RCA component ports, and perhaps a port for composite sync as well. That way we could take his ps2, set it up to RGB output, and then plug in component and composite sync, and I think that should show if my actual RGB solder job is good or not. If the ps2 works, great. That means there would an issue with my original VGA wiring, perhaps the sync combiner is an issue. My original plan was to use this tv via VGA so I could play emulation via computer, and it seems like it would be a whole lot easier to do this if I just use windows 7 instead of linux, as that would likely allow me to output csync over vga, which simplifies everything as well.
That's a great idea. You don't need a 4th RCA jack for sync - just plug it into the TV's AV input.
mccutheon wrote:Continuing on the with the trinitron mod, I believe I just noticed a major mistake. If you look at the wiring diagram of the VGA port I am using, I have my 910 ohm muxing resistors wired AFTER the 75 ohm grounding resistors.
Yes, what you've basically done is connect the RGB lines straight to ground. That will get you no image whatsoever. Your second diagram is correct.
mccutheon
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Re: TV RGB mod thread

Post by mccutheon »

matt wrote: That's a great idea. You don't need a 4th RCA jack for sync - just plug it into the TV's AV input.
I was thinking that if I had everything opened up, and was adding the 3 RCA plugs, I might as well add a 4th for composite sync on the back, to keep things nice and clean. I had soldered my sync line to the Front AV video connection as previously discussed, and I think that means that is the only port that composite sync can currently attach to, unless I'm mistaken. I might end up putting this CRT into a cabinet someday, and perhaps it would be useful to have RGB sync access at the rear of the TV, even though I intend to only use it via vga/computer. I must admit I do like the retro/classic look of the cables connected to the front.

An interesting thing I noticed about the VGA header I am using is that pin 10 is not actually tied to the other grounds, or VGA chassis. I was under the impression that all the VGA grounds were tied together, and to the VGA chassis. Ultimately this probably doesnt matter because I presume pin 10 on the PC is grounded, so ultimately its grounded on the Header side of the VGA cable in my tv. I am not grounding anything on pin 10.

Another note for any who might come across it and don't know. If you are testing lines to confirm continuity, most multimeters won't confirm continuity if there is more then 1000 ohm of resistance in line. I tested the middle transistor leg in my passive sync combiner and wasn't getting continuity with the 10k resistor in line, so i ripped it apart and grabbed a new 10k, did a quick continuity test on that one, nothing and now I'm suspicious, quick google, and then a laugh about my mistake, and solder everything back together.
amxcs
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Joined: Wed Dec 21, 2022 1:28 pm

Re: TV RGB mod thread

Post by amxcs »

Surfovod wrote:Hello.
I have a TV Panasonic TC-2155R, with a chassis MX-3C http://gaf.kz/tv/AN.PDF, a video processor AN5192K http://gaf.kz/tv/MX.pdf.
I want to connect a 60-in-1 Chinese gaming board for vertical games.
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Connected according to the picture. I picked up all the necessary resistances and ceramic capacitors. The colors are very good, bright, they delight me, but there is one problem - the geometry of the picture is broken (the image is shifted). I read the whole topic, I realized that the reason for this is a comb filter. It is recommended to connect directly to the luma S-video, but I do not have such an input, only composite (AB). I tried to connect directly to Y-in (43) and CHROMA-in (48) there is no effect, I even tried to connect to the contacts of vertical and horizontal synchronization (45,46) (the geometry is not straightened). I would configure the geometry through the service menu, but the original remote is lost, I don’t know how to enter the service menu without it.
I am in despair, ready to throw the TV into the abyss.

Please tell me how to get around this comb filter? are there any methods?
Or maybe it is possible to enter the service menu without the original remote?
I would be grateful for any help
Hello,
I have Panasonic TC21S10R with MX-3 chassis.
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Can you help me with the values of these "all the necessary resistances and ceramic capacitors".
Thanks!
amxcs
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Re: TV RGB mod thread

Post by amxcs »

I connected according to this scheme, directly to the IS, the quality is good, but the picture is dark. Where should I look for the problem?
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abispac2
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Re: TV RGB mod thread

Post by abispac2 »

Hey everyone, i scored another disney tv 13 inches, its gonna be my secnd one, but i lost my notes. I was wondering if someone could be kind enought to point me what the correct values resistors are for the mux mod? thanks alot.

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mccutheon
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Re: TV RGB mod thread

Post by mccutheon »

abispac2 wrote:Hey everyone, i scored another disney tv 13 inches, its gonna be my secnd one, but i lost my notes. I was wondering if someone could be kind enought to point me what the correct values resistors are for the mux mod? thanks alot.

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Your OSD inline resistors, R121, R122 and R123 for blue, green red, are 4700 ohms. According to the below table, which I grabbed from the CRT database, That means you would include 910 if you put diodes on the OSD lines, or 750 if you do not put diodes.

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it looks like the 3 680 ohm resistors, R102, R103, and R104, are your grounded voltage divider resistors that you would remove.

Maybe someone else can chime in and confirm.
abispac2
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Re: TV RGB mod thread

Post by abispac2 »

Im tempted into doing it the easy way, as the segaholic, because over the past mods i had make, the menu buttons give me a weird behavior, son im not sure if is about the mod or the tv buttons didnt worked previusly, but now that i think about it, ima put it to the test, as this buttons are working just fine, so ima perform the mod and if the button behave diferent after that, than something funny its going on, yeah i think 750 oms are gonna do the job. thanks.
amxcs
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Re: TV RGB mod thread

Post by amxcs »

I removed the capacitors and resistors, just connected directly to the IC and the picture is no longer dark.
meximetal96
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Re: TV RGB mod thread

Post by meximetal96 »

Hello everyone, first time posting here. I have a Toshiba MD20FP3 that I would love to RGB mod, however I'm having a hard time determining if it's a good candidate for modding. I have a pdf of the service manual and have located the micom and jungle chip, but I have some concerns. I tried looking up datasheets of the micom chip and jungle chip and have come up short, so I wasn't able to determine whether or not the OSD is digital or analog. According to the diagrams there aren't any 0.1 uF capacitors between the micom and jungle chips, and here are some relevant screenshots from the service manual. Can this TV be rgb modded? I can provide more screenshots, but I'm really hoping this can be RGB modded.
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amxcs
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Re: TV RGB mod thread

Post by amxcs »

Panasonic TC21S10R with MX-3 chassis

The mod consists of only 3 capacitors, a switch, scart sockets and some cables.
The picture is perfect!
The only drawback is that the service menu does not allow to move the picture a little more to the right, but it is not a problem.
When the OSD is needed, it is turned on by the switch - the green color changes a little, but only for a moment while settings are made.

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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Odd set you have there.
The OSD RGB go thu 2.2k (red is 1.8k?) resistors and terminated with 910r

If the supply video voltage is an assumed 5v then that OSD signal will be 1.46v (Red 1.67) by the time it hits the jungle.

Standard scart signal is 1.4v before termination. So connecting directly was your best option. Nice work.

Check 100 IRE and make sure you dont have any white crush, hard to tell from your pics.
amxcs
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Re: TV RGB mod thread

Post by amxcs »

How to check 100 IRE?
What is white crush?
amxcs
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Re: TV RGB mod thread

Post by amxcs »

Now I've noticed that on a black background, if there are white letters, they color the whole row very slightly white.
How can I fix this? And is this white crush?
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buttersoft
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Re: TV RGB mod thread

Post by buttersoft »

amxcs wrote:Now I've noticed that on a black background, if there are white letters, they color the whole row very slightly white.
How can I fix this? And is this white crush?
This is normally caused by poor regulation somewhere. Hard to fix on a lot of older sets. I would suggest replacing all the electrolytics on the neckboard as a first step. But that's not a guarantee.

A black/white crush is when one end of the brightness range gets squashed up to the end. So, in a hypothetical example, the middle third of the picture brightness range (itself normally 0-0.7Vp-p) is ok, but anything dimmer than that turns fully black, and all the brighter stuff becomes white (or just saturated colour without any gradation).
flyingflygon
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Re: TV RGB mod thread

Post by flyingflygon »

Samsung GX Mux Mod completed and fully documented: https://github.com/brendanseattle/Samsu ... /main/KG-1

Make: Samsung
Chassis: KG-1
Model: GXE-1395

This is a fairly standard mux but has some Samsung-specific things to take care of in order to use RGB input. The set looks lovely over RGB. The speakers steal the show and it feels like your own arcade.
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Akuji
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Re: TV RGB mod thread

Post by Akuji »

Hello!

I currently own a PVM-14N6U and one major annoyance is the fact that it does not support component, only RGB. However, upon looking at the service manual I see lots of YUV related stuff mentioned, such as the RGB inputs mentioning R-Y, Y, and B-Y as options and the jungle chips mentioning a YUV Line and switch. I was wondering, is there actually some sort of buried Component support that I could tap into, maybe something I could integrate into an "RGB/Component" toggle switch just like most CRT mods incorporate a RGB/CVBS toggle switch? I'm not educated enough on this stuff to know if what I'm asking for is impossible so let me down easy, lol. Obviously I can look into simply buying a COMP2RGB, but it would be really nice if I could make my PVM support component "natively" just like most others.

Here's the link to the block diagram page of the service manual.
https://archive.org/details/ssm-20-n-5- ... 5/mode/2up
https://crtdatabase.com/crts/sony/sony-ssm-14n6u
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matt
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Re: TV RGB mod thread

Post by matt »

Akuji wrote:Hello!

I currently own a PVM-14N6U and one major annoyance is the fact that it does not support component, only RGB. However, upon looking at the service manual I see lots of YUV related stuff mentioned, such as the RGB inputs mentioning R-Y, Y, and B-Y as options and the jungle chips mentioning a YUV Line and switch. I was wondering, is there actually some sort of buried Component support that I could tap into, maybe something I could integrate into an "RGB/Component" toggle switch just like most CRT mods incorporate a RGB/CVBS toggle switch? I'm not educated enough on this stuff to know if what I'm asking for is impossible so let me down easy, lol. Obviously I can look into simply buying a COMP2RGB, but it would be really nice if I could make my PVM support component "natively" just like most others.

Here's the link to the block diagram page of the service manual.
https://archive.org/details/ssm-20-n-5- ... 5/mode/2up
https://crtdatabase.com/crts/sony/sony-ssm-14n6u
The jungle chip definitely has YUV input pins, which are grounded through a set of capacitors (just like in their consumer TVs). I wouldn't be surprised if you could mod it for component. It's something to look into for sure!

Looking at the CXA2060BS datasheet, it looks like the external YUV input pins aren't configured to take sync, so you might have to fudge it by splitting the Y signal like on the BA-4/4D component mod. Just like those mods, the chip can be configured for external or inernal Y input, so how the mod is done would depend on how the I2C input is configured. Either way, it should work.

https://pdf1.alldatasheet.com/datasheet ... 060BS.html
Akuji
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Re: TV RGB mod thread

Post by Akuji »

matt wrote:
Akuji wrote:Hello!

I currently own a PVM-14N6U and one major annoyance is the fact that it does not support component, only RGB. However, upon looking at the service manual I see lots of YUV related stuff mentioned, such as the RGB inputs mentioning R-Y, Y, and B-Y as options and the jungle chips mentioning a YUV Line and switch. I was wondering, is there actually some sort of buried Component support that I could tap into, maybe something I could integrate into an "RGB/Component" toggle switch just like most CRT mods incorporate a RGB/CVBS toggle switch? I'm not educated enough on this stuff to know if what I'm asking for is impossible so let me down easy, lol. Obviously I can look into simply buying a COMP2RGB, but it would be really nice if I could make my PVM support component "natively" just like most others.

Here's the link to the block diagram page of the service manual.
https://archive.org/details/ssm-20-n-5- ... 5/mode/2up
https://crtdatabase.com/crts/sony/sony-ssm-14n6u
The jungle chip definitely has YUV input pins, which are grounded through a set of capacitors (just like in their consumer TVs). I wouldn't be surprised if you could mod it for component. It's something to look into for sure!

Looking at the CXA2060BS datasheet, it looks like the external YUV input pins aren't configured to take sync, so you might have to fudge it by splitting the Y signal like on the BA-4/4D component mod. Just like those mods, the chip can be configured for external or inernal Y input, so how the mod is done would depend on how the I2C input is configured. Either way, it should work.

https://pdf1.alldatasheet.com/datasheet ... 060BS.html
Glad to hear that it might be doable! To add onto this, do you think it would be possible to route the RGB signals automatically to the Component pins when SoG is enabled? That way I could turn the PVM's SoG menu option into a Component option and avoid any external toggle switches.

I tried looking into it and making some educated guesses. This PVM has an option to use Sync-on-Green instead of RGBS in the settings, which I think is why Analog G is routed to Y1 on the decoder chip at the same time that Ext Sync is routed to Y2, assuming Line/RGB (or Line/YUV) is enabled. I think Line/YUV from the controller chip might be repurposed for Sync-On-Green since Line/YUV's connection to YUV SW on the Decoder is paired up right next to the RGB1 lines on its diagram, but Line/RGB is also the only way for VS1 to get a signal (VS1 on = V2, VS1 off = V1?). Both lines still enable the video signal to switch to its RGB video input. So maybe when Line/RGB outputs a signal the route is normal, but when Line/YUV outputs a signal the RGB lines are rerouted to their Y1/ER-Y/EB-Y equivalents? I think I can see a method on a technical level but I still have no idea how to translate this into a real world mod.
mccutheon
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Re: TV RGB mod thread

Post by mccutheon »

Hey Hey guys,

Wanted to give a bit of an update on the RGB mod of my sony trinitron KV-20m40 BA-4 chassis.

Success!

I can now boot my main pc with the groovyarcade live boot software on usb, and connect my computer, via DVI to VGA cable, to the VGA plug i put together, with the standard passive sync combiner from retroRGB.

I am going to document things more in full, but I think a misunderstanding about grounds has been causing me issues this whole time.

Sucessful screen test
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boot up screen
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sample game
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------

So its nice to know that my R G B and sync lines, as well as blanking seems to be functional.

One thing i can't quite figure out yet though.

I have my blanking switch which is essentially on/off. I thought it might be neat to have two sets of RGB inputs for the tv, so I bought a 12 pin switch, a 4PDT. I have my VGA side of things, 4 wires for R G B sync, Those are on the 1 side of the switch, and in the middle switched part, where the R G B lines go to the jungle as usual, and the sync pin is wired to the front AV 2 composite line

I wanted to install 3 RCA ports, each wired up to the other side of the switch, so that I can switch between VGA and RCA RGB, which I can use to run a ps2 in full RGB mode. I've confirmed that you can use third party ps2 multi av cables that include both component and composite, to get full RGB from a ps2 to a monitor. I took the RCA adapters, grounded a 75 ohm resistor on each color line, and included the same 910 ohm resistors on each external line like I did with my VGA port. The VGA RGB and sync lies are grounded on the tv board, and I connected that ground over to the RCA ports as well. I ran those 3 lines into the other side of 12 pin switch, leaving the 4th pin on the RCA side empty. For this sync, I thought I would just run the ps2 composite cable into the back AV1 composite port.

The result is a very poor looking picture when I have RGB blanking turned on

Blanking turned on
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Blanking turned off
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I think I must be missing something here. Anyone have any thoughts on the poor picture quality? I followed a lot of the standard RCA/BNC mod install videos.
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matt
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Re: TV RGB mod thread

Post by matt »

Akuji wrote: Glad to hear that it might be doable! To add onto this, do you think it would be possible to route the RGB signals automatically to the Component pins when SoG is enabled? That way I could turn the PVM's SoG menu option into a Component option and avoid any external toggle switches.

I tried looking into it and making some educated guesses. This PVM has an option to use Sync-on-Green instead of RGBS in the settings, which I think is why Analog G is routed to Y1 on the decoder chip at the same time that Ext Sync is routed to Y2, assuming Line/RGB (or Line/YUV) is enabled. I think Line/YUV from the controller chip might be repurposed for Sync-On-Green since Line/YUV's connection to YUV SW on the Decoder is paired up right next to the RGB1 lines on its diagram, but Line/RGB is also the only way for VS1 to get a signal (VS1 on = V2, VS1 off = V1?). Both lines still enable the video signal to switch to its RGB video input. So maybe when Line/RGB outputs a signal the route is normal, but when Line/YUV outputs a signal the RGB lines are rerouted to their Y1/ER-Y/EB-Y equivalents? I think I can see a method on a technical level but I still have no idea how to translate this into a real world mod.
That might be tricky. The RGB signals go straight from the rear panel to RGB input pins on the jungle chip, with no switching IC in between. So there's no way to redirect the signals electronically to the YUV input pins. The mod is definitely possible, but it might not be as streamlined as the N5U RGB restoration.

The CXA2060SB is basically the same as the CXA2061 and CXA2133 used in the BA-4 & BA-4D consumer Trinitrons.
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matt
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Re: TV RGB mod thread

Post by matt »

mccutheon wrote:One thing i can't quite figure out yet though.

I have my blanking switch which is essentially on/off. I thought it might be neat to have two sets of RGB inputs for the tv, so I bought a 12 pin switch, a 4PDT. I have my VGA side of things, 4 wires for R G B sync, Those are on the 1 side of the switch, and in the middle switched part, where the R G B lines go to the jungle as usual, and the sync pin is wired to the front AV 2 composite line

I wanted to install 3 RCA ports, each wired up to the other side of the switch, so that I can switch between VGA and RCA RGB, which I can use to run a ps2 in full RGB mode. I've confirmed that you can use third party ps2 multi av cables that include both component and composite, to get full RGB from a ps2 to a monitor. I took the RCA adapters, grounded a 75 ohm resistor on each color line, and included the same 910 ohm resistors on each external line like I did with my VGA port. The VGA RGB and sync lies are grounded on the tv board, and I connected that ground over to the RCA ports as well. I ran those 3 lines into the other side of 12 pin switch, leaving the 4th pin on the RCA side empty. For this sync, I thought I would just run the ps2 composite cable into the back AV1 composite port.
Can you describe the poor image quality you're seeing? It's not obvious from the pic (although the 2nd one is obviously composite video).

I imagine you've done something like duplicate the termination and/or mux resistors. It's hard to follow from your description, though, so you'll have to clarify exaclty how it's wired up.
mccutheon
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Re: TV RGB mod thread

Post by mccutheon »

matt wrote:
Can you describe the poor image quality you're seeing? It's not obvious from the pic (although the 2nd one is obviously composite video).

I imagine you've done something like duplicate the termination and/or mux resistors. It's hard to follow from your description, though, so you'll have to clarify exaclty how it's wired up.
Here is a link to the 4PDT switch I mentioned

https://www.amazon.ca/dp/B07VHCB4JJ?psc ... ct_details

I put together a rough version 1 schematic of my wiring for the VGA port and RCA plugs, and the switched signal to the tv. Note that the bottom right pin isn't connected to anything. All grounds are shared, including the VGA sync line even though its not shown in the picture.

Everyone who looks at it describes it as 'really blue'. It is hard to describe, almost like its 3d, or doubled or something like that.

here is a close up of the X button text on the screen on composite:
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here it is in RGB
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Something else I noticed is that if I unplug the blue signal, then I am left with a yellow-green tinted screen as would be expected i think but it also looks more 'correct'. If I leave blue plugged in but unplug either of the other two, I get both the screen color distortion as well as this weird ghosting seen in the RGB screens. Perhaps there is an issue with the wiring on my blue connection.
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mccutheon
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Re: TV RGB mod thread

Post by mccutheon »

Turns out it actually was the blue connection. I whipped up a new one with new resistors, plugged it in, and it worked right away. Looking pretty good! I wonder what the issue was. Perhaps I'll rip apart the connection and see what I screwed up.

EDIT : Just took apart the blue connector, looks like i somehow swapped the 75 and 910 ohm resistors when I was putting them together, yikes
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Akuji
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Re: TV RGB mod thread

Post by Akuji »

matt wrote:
Akuji wrote: Glad to hear that it might be doable! To add onto this, do you think it would be possible to route the RGB signals automatically to the Component pins when SoG is enabled? That way I could turn the PVM's SoG menu option into a Component option and avoid any external toggle switches.

I tried looking into it and making some educated guesses. This PVM has an option to use Sync-on-Green instead of RGBS in the settings, which I think is why Analog G is routed to Y1 on the decoder chip at the same time that Ext Sync is routed to Y2, assuming Line/RGB (or Line/YUV) is enabled. I think Line/YUV from the controller chip might be repurposed for Sync-On-Green since Line/YUV's connection to YUV SW on the Decoder is paired up right next to the RGB1 lines on its diagram, but Line/RGB is also the only way for VS1 to get a signal (VS1 on = V2, VS1 off = V1?). Both lines still enable the video signal to switch to its RGB video input. So maybe when Line/RGB outputs a signal the route is normal, but when Line/YUV outputs a signal the RGB lines are rerouted to their Y1/ER-Y/EB-Y equivalents? I think I can see a method on a technical level but I still have no idea how to translate this into a real world mod.
That might be tricky. The RGB signals go straight from the rear panel to RGB input pins on the jungle chip, with no switching IC in between. So there's no way to redirect the signals electronically to the YUV input pins. The mod is definitely possible, but it might not be as streamlined as the N5U RGB restoration.

The CXA2060SB is basically the same as the CXA2061 and CXA2133 used in the BA-4 & BA-4D consumer Trinitrons.
Maybe this can be handled between the input daughter board and the main board? Apparently the PVM just uses a JST EH connector cable to connect them together and the resistors look like they're on the daughter board. The 68pF ceramic caps are on the main board though, but that's it in terms of what they touch before they get to the decoder. What if there was some sort of multiplexer in between that cable that routed RGB like normal but if Line/YUV on the controller goes high it cuts off the RGB line connection and instead pipes it directly to 3 wires on the decoder's component pins (with their own 68pF caps that go to ground I assume)? I don't know if there's any multiplexer breakout boards that would be good for this or if it's a good idea to use one at all. It's definitely more complicated but I personally would prefer the hassle to have a more seamless feeling mod.
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matt
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Re: TV RGB mod thread

Post by matt »

Akuji wrote:Maybe this can be handled between the input daughter board and the main board? Apparently the PVM just uses a JST EH connector cable to connect them together and the resistors look like they're on the daughter board. The 68pF ceramic caps are on the main board though, but that's it in terms of what they touch before they get to the decoder. What if there was some sort of multiplexer in between that cable that routed RGB like normal but if Line/YUV on the controller goes high it cuts off the RGB line connection and instead pipes it directly to 3 wires on the decoder's component pins (with their own 68pF caps that go to ground I assume)? I don't know if there's any multiplexer breakout boards that would be good for this or if it's a good idea to use one at all. It's definitely more complicated but I personally would prefer the hassle to have a more seamless feeling mod.
I'm sure that's possible - you'd have to make a separate video switching board and have it triggered by the RGB or YPbPr blanking voltage.

Or you could just add separate jacks for YPbPr. The question is whether or not the jungle chip is configured for internal or external Y input.

I do have a 14N5U at home that I've been planning to mod for a while. Hopefully I'll have time in the next few days to sit down and see if I can figure out a mod.
Akuji
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Re: TV RGB mod thread

Post by Akuji »

matt wrote:
Akuji wrote:Maybe this can be handled between the input daughter board and the main board? Apparently the PVM just uses a JST EH connector cable to connect them together and the resistors look like they're on the daughter board. The 68pF ceramic caps are on the main board though, but that's it in terms of what they touch before they get to the decoder. What if there was some sort of multiplexer in between that cable that routed RGB like normal but if Line/YUV on the controller goes high it cuts off the RGB line connection and instead pipes it directly to 3 wires on the decoder's component pins (with their own 68pF caps that go to ground I assume)? I don't know if there's any multiplexer breakout boards that would be good for this or if it's a good idea to use one at all. It's definitely more complicated but I personally would prefer the hassle to have a more seamless feeling mod.
I'm sure that's possible - you'd have to make a separate video switching board and have it triggered by the RGB or YPbPr blanking voltage.

Or you could just add separate jacks for YPbPr. The question is whether or not the jungle chip is configured for internal or external Y input.

I do have a 14N5U at home that I've been planning to mod for a while. Hopefully I'll have time in the next few days to sit down and see if I can figure out a mod.
If I had to guess the Y input is internal based on how it looks like Sync-on-Green is implemented, where Analog G goes into Pin 4/Y1 of the decoder at the same time that Line/YUV -> YUV SW gets power, which for that to work it looks like EY IN would be disabled in that config.

Image

Assuming you were switching the route when you receive the YPbPr voltage you could probably connect Analog G to Output Pin 5 of the Video Switch directly, that way it doesn't go to the original RGB line but still goes down the sync-related path that it originally went to (doing this skips C404 though so a similar cap would be needed on the wire). The other two just go to the R-Y and B-Y pins after they're lifted off the board to un-ground them.

If you can come up with the mod for this that would be fantastic. I'm hesitant on adding jacks because I don't really see any good spots to put them (my PVM is almost flush to the wall in my current setup and the input area has a big daughter board right behind it) and I really don't want to cut anything on my PVM in general. Plus using the same jacks would work great with the gscartsw that I'm still waiting on, I'd just need an adapter.
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matt
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Re: TV RGB mod thread

Post by matt »

Akuji wrote:If I had to guess the Y input is internal based on how it looks like Sync-on-Green is implemented, where Analog G goes into Pin 4/Y1 of the decoder at the same time that Line/YUV -> YUV SW gets power, which for that to work it looks like EY IN would be disabled in that config.

Image

Assuming you were switching the route when you receive the YPbPr voltage you could probably connect Analog G to Output Pin 5 of the Video Switch directly, that way it doesn't go to the original RGB line but still goes down the sync-related path that it originally went to (doing this skips C404 though so a similar cap would be needed on the wire). The other two just go to the R-Y and B-Y pins after they're lifted off the board to un-ground them.

If you can come up with the mod for this that would be fantastic. I'm hesitant on adding jacks because I don't really see any good spots to put them (my PVM is almost flush to the wall in my current setup and the input area has a big daughter board right behind it) and I really don't want to cut anything on my PVM in general. Plus using the same jacks would work great with the gscartsw that I'm still waiting on, I'd just need an adapter.
I wouldn't take that for granted. The YUV inputs on the jungle chip aren't in use, so there's no reason to assume that Sony would have configured it one way or the other. The schematic does appear to show some half baked YUV-related circuitry but it's not enough to actually use it as an input. It looks like they intended to include it but changed their minds before the PCB design was finished.

The SOG option is missing in the menu of my 14N5U when RGB is enabled. It might not be available on all models.

I wrote about the component mod on consumer Trinitrons in this thread. Worst case scenario, the mod could be done the same way:

https://shmups.system11.org/viewtopic.php?f=6&t=68134
Akuji
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Re: TV RGB mod thread

Post by Akuji »

matt wrote:I wouldn't take that for granted. The YUV inputs on the jungle chip aren't in use, so there's no reason to assume that Sony would have configured it one way or the other. The schematic does appear to show some half baked YUV-related circuitry but it's not enough to actually use it as an input. It looks like they intended to include it but changed their minds before the PCB design was finished.

The SOG option is missing in the menu of my 14N5U when RGB is enabled. It might not be available on all models.

I wrote about the component mod on consumer Trinitrons in this thread. Worst case scenario, the mod could be done the same way:

https://shmups.system11.org/viewtopic.php?f=6&t=68134
Looks like the third menu page in the settings is only available on the original RGB versions, so that's why.

Image

I've contacted a CRT repairman close to me in Cali to see if maybe he may be able to attempt this with me. I hope my ideal scenario can work.
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matt
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Re: TV RGB mod thread

Post by matt »

Akuji wrote: Looks like the third menu page in the settings is only available on the original RGB versions, so that's why.


I've contacted a CRT repairman close to me in Cali to see if maybe he may be able to attempt this with me. I hope my ideal scenario can work.
Duh, yeah that's because I was just jumping the RGB switch contacts and hadn't populated the RGB enable resistor near the micon. After doing that the 3rd page of the menu shows up fine.
maffatil
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Re: TV RGB mod thread

Post by maffatil »

HI I'm trying looking to mod a Toshiba 27A23. It has an OEC7090 and M61283 chroma chips. I know other Toshiba's with a nearly identical board layouts and the same chips can be modded, some with the switch mod and some via muxxing, but I want to attempt a mux mod.
However there seems to be some extra components in red, green, blue and blanking lines:
Spoiler
Image
I know from the mods on the similar tv's most of the extra components should be left, but I'm concerned about the diodes on the blue and blanking signals. Do I need to do anything different than normal if the diodes are present? I don't think the mods for the similar tv's did anything special, but I just want to make sure I don't wreck anything.
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