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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 01, 2020 3:21 pm 



Joined: 26 Mar 2020
Posts: 21
MarkOZLAD wrote:

OSD will continue to work because it is fed into a separate set of RGB pins on the jungle.



One other question on this - I have a SNES 1chip rev3 that outputs sync on Luma - will it work with this mod or I need to do the rgb bypass for the SNES and change it to c-sync? Or maybe I could do something else like use a splitter on the SNES cable and run the green (Luma IS green, right?) both to the new bnc input and any one of the original composite inputs?


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 01, 2020 11:23 pm 



Joined: 18 May 2017
Posts: 743
Exclamation wrote:
MarkOZLAD wrote:

OSD will continue to work because it is fed into a separate set of RGB pins on the jungle.



One other question on this - I have a SNES 1chip rev3 that outputs sync on Luma - will it work with this mod or I need to do the rgb bypass for the SNES and change it to c-sync? Or maybe I could do something else like use a splitter on the SNES cable and run the green (Luma IS green, right?) both to the new bnc input and any one of the original composite inputs?


Luma is most likely perfectly fine.
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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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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 02, 2020 3:44 pm 



Joined: 16 Jun 2020
Posts: 53
Ok, I need some help. I've been working on my Panasonic CT-32G4A. I've determined that it's moddable since it's just about the same as the one devalis modded here: viewtopic.php?p=1226551#p1226551 which has the exact same Jungle IC as mine as he said here: https://forums.nesdev.com/viewtopic.php?t=11648

Here is a basic diagram of the circuit between the Microcontroller and the Jungle chip:

Image

Full schematic here: http://www.planetatecnico.com/foro/down ... p?id=11955

There are no diode or grounding resistors on the RGB lines. Using the OSD Mux chart for 2.2k in-line resistors I used 270 for my Mux lines. The chart called for 283 and it was the closest I had.

Image

I am using a VGA connector as input. To start, I did nothing with the blanking line. My intention was to just activate the OSD on the TV with the RGB Mux in place to see if I got anything when the OSD was showing. I got nothing. The OSD did turn black, though, instead of green. I could see this whenever I set the input back to "TV" and saw the channel # displayed against the static background. It did this whether or not the VGA connector had anything plugged in or not. It seems just having those lines muxed in did it. At one point the OSD turned blue, and I checked and saw that my Blue MUX line had gotten disconnected, but R and G were still hooked in so that made sense.
Then I tried pulling Ys to 5V by hooking it to pin 9 on my VGA connector (not pictured in diagram). When I did that the TV screen was solid black no matter what I did.

Spoiler: show
OSD with mux circuit in place, nothing connected to VGA:

Image

And if I remove the 75 ohm ground terminations:

Image


Jungle IC: https://pdf1.alldatasheet.com/datasheet ... 5165K.html

I should note that I was testing with a PC using a Radeon HD 6450 card flashed with ATOM-15 for 15kHz and Composite Sync using its DVI-I connector with a VGA adapter and booting it to FreeDOS. It's the only 15kHz RGB source I have at the moment, so I can't say for 100% certain that the source is valid.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 02, 2020 11:21 pm 



Joined: 18 May 2017
Posts: 743
Osirus wrote:


These Jungles do not require the caps that you've added on the external RGB lines.


EDIT: Looks like I was wrong. It is the AN5192K that doesn't need caps, I just assumed this would be the same.I checked some schematics and found caps on the rgb lines when this jungle is used.

Sorry!
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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


Last edited by MarkOZLAD on Thu Aug 20, 2020 11:20 pm, edited 1 time in total.

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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 12:10 am 



Joined: 31 May 2020
Posts: 7
UPDATE 2:
Did some more tracing around and found

3 Zener Diodes MTZ10C
DZ209 Y
DZ210 Pb
DZ208 Pr

3 (5?) 330ohm 1/6W Resistors (this really confuses me. There's 3 that are close in number so I am making the assumption those are the ones to bring the voltage down, 330ohm, the other two I am unsure of. Probably will just leave them off, for now.)
R231 Pb
R232 Pr

R712 Y
R711 Pb
R714 Pr

3 15nF 50v (possibly) or 100v (service manual says 100v) Ceramic Caps
C236 Y
C235 Pb
C205 Pr



UPDATE: I found that there are headers on the motherboard for YPbPr so I can do component. The service menu also has option 12 TV<->AV and TV<->AV<->DVD which someone told me if I swap it, it should enable the component headers.

The only issue I am working on right now is I need to rebuild the components missing for component.
C236 Y
C235 Pb
R714 Pr
C205 Pr

Had someone help me research. Looks like 15nf caps and 330 ohm 1/6w resistor is used. Will test and report back.

Those are what I saw missing. Hopefully this all won't be a waste. Trying to track down the values for the 3 caps and resistor.


Hi Everybody!

I have recently obtained a Samsung TXM1491FX-XAA and found the following service manual for it. I have another Sony TV that happens to have digital RGB not analog so I was unable to mod that one. I am unable to actually tell if this is digital or analog RGB. The connector that the composite AV is on looks like a SCART connector would actually fit there so I assume this had a EUR equivalent that actually had SCART w/ RGB possibly.

I model number for the IC is Philips TDA9377 based on the service manual and it references PAL/SECAM/NTSC making me wonder if this supports 50/60 as well.

Image I have highlighted pins 51 through 53 which I believe are the RGB for the OSD which I should be able to jack into with pin 50 which is the blanking input. However I also noticed pins 46 though 48 which may be the native RGB input along with pin 45 which may be the video input switch to go to RGB.

Wondering where everyone suggests I go to from here.


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 6:12 am 



Joined: 18 May 2017
Posts: 743
I think you’ll find you won’t be able to scart mod this. I think it’ll be component mod only. Change the service menu to include the DVD option.
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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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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 6:22 am 



Joined: 31 May 2020
Posts: 7
MarkOZLAD wrote:
I think you’ll find you won’t be able to scart mod this. I think it’ll be component mod only. Change the service menu to include the DVD option.


Hopefully I can restore it with everything I bought. Any ideas why there’s be two extra resistor spots?

Do all TVs that have a DVD player use component to interface? Any easy way to tell?


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 1:56 pm 



Joined: 18 May 2017
Posts: 743
KitsuneMulder wrote:
Had someone help me research.


I think I know the guy....
_________________
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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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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 2:37 pm 



Joined: 31 May 2020
Posts: 7
MarkOZLAD wrote:
KitsuneMulder wrote:
Had someone help me research.


I think I know the guy....


Just realized...small world.


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 7:53 pm 



Joined: 16 Jun 2020
Posts: 53
MarkOZLAD wrote:
Osirus wrote:


These Jungles do not require the caps that you've added on the external RGB lines.


Thanks. I now see that you've consulted on this chip before: viewtopic.php?p=1370408#p1370408

I'm going to snip the RGB lines between the Micro and Jungle and first see if I can get my external input working at all before working on Mux. The circuit board makes this very easy as all 4 lines have jumpers next to eachother on top of the board just before the Jungle inputs.


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 03, 2020 9:28 pm 



Joined: 03 Aug 2020
Posts: 1
Has anyone figured out if the mod for the LA7674 chip, where the blanking signal on the blue input, is possible?


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 04, 2020 3:25 pm 



Joined: 04 Aug 2020
Posts: 1
Hey all, I'm brand new to these RGB mods and attempted my first one yesterday with mixed results.

I didn't find this thread until after the fact, I actually asked a friend about it and he helped me get to this point. It's a new-old-stock 14" Vision Electronics VIS-146R that uses the Philips TDA8361 jungle IC and a CTV222S OSD controller. I sent him some photos of the top/bottom of the board and this is what I've ended up with:

- grounded RGB inputs via 91ohm resistors

- attached RGB inputs via 110ohm resistors to the spot where the OSD RGB lines (via resistors of their own) and voltage divider resistors meet (I think that's what they're for, tied to ground)

- the RGB inputs and OSD RGB signals go through the same wires to 3 capacitors right before entering the jungle IC

- 5V VCC taken from OSD controller, into 10K POT, into a switch that switches between OSD and RGB blanking (the TDA8361 wants somewhere around 3V for RGB blanking, the POT is just for testing and will be replaced by a resistor later)

Here's a poorly annotated photo.
Spoiler: show
Image


And here are the results.
Spoiler: show
Image

Image


As you can see, there's what he called "high voltage rings" on the left. Without a game console plugged in, it's still there when I increase the brightness until the blacks are no longer black. I've tried decreasing the flyback voltage to no effect, and also replaced the 2 capacitors on the neckboard and 1 capacitor next to the flyback (I saw some threads online that indicated it may be due to weak HV caps) which didn't change anything either. There are more high voltage caps around the flyback that I don't have replacements of right now.

The second problem is hard to get on video, but the image is sort of jittery as if something isn't grounded properly. It's especially noticeable on the edges of objects like the "Super Mario Kart" title box seen above.

Any ideas? What would happen if I removed the 3 capacitors before the jungle IC and connected the RGB + OSD lines directly to the IC itself?


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 10, 2020 6:05 am 



Joined: 26 Mar 2020
Posts: 21
MarkOZLAD wrote:
Exclamation wrote:
MarkOZLAD wrote:

OSD will continue to work because it is fed into a separate set of RGB pins on the jungle.



One other question on this - I have a SNES 1chip rev3 that outputs sync on Luma - will it work with this mod or I need to do the rgb bypass for the SNES and change it to c-sync? Or maybe I could do something else like use a splitter on the SNES cable and run the green (Luma IS green, right?) both to the new bnc input and any one of the original composite inputs?


Luma is most likely perfectly fine.


Finally got all my parts and got everything back together but I get this https://i.imgur.com/g8Awsv9.jpg
- when I turn on osd it looks normal, if a little soft - the only thing I did different than what you said was I removed r165 and powered d003 from a through hole right after r165 output pad because all of these are smd and it was just much easier access that way - also removed d355 (“ma110 mix”?) on the same circuit because it was going to vm mute on 2 different connectors and I assume that would mute my volume? - hope that wasn’t my mistake - er.. maybe hope that was my mistake because it would be easy to add back in - anyway it looked like the idea of powering from d003 was to not be powering anything before 003 - any idea what’s going on here?


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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 10, 2020 10:22 am 



Joined: 18 May 2017
Posts: 743
What type of sync are you using Exclamation?
_________________
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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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 Post subject: Re: TV RGB mod thread
PostPosted: Mon Aug 10, 2020 3:23 pm 



Joined: 26 Mar 2020
Posts: 21
MarkOZLAD wrote:
What type of sync are you using Exclamation?



Not sure - can test the lead later today, but it's just a cheap eBay cable not specified sync type - I did notice last night that if I disconnect the rgb lines I still get a real faint picture with no color and that goes away or gets blanked when I turn on osd - sounds like we can assume the cable I have is using composite sync and when I get c-sync retro-access cables in a couple weeks that will take care of it?

Edit: confirmed the cheapo eBay cables are wired with the sync plug connected to the composite pin, and also hooked up my SNES with composite cable and it also has a super dim b+w picture that blanks on osd - so yeah, looks like it will work normally when I'm not sending composite on top of rgb, yes?


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 11, 2020 6:59 am 



Joined: 12 May 2020
Posts: 3
@Enternal

Have you had any luck with RGB modding that PVM-14L1?

I've got a SSM-20L1 that I'd love to be able to feed RGB (or component) into. I believe it has the same jungle, or the whole board is much the same.


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 11, 2020 10:49 am 



Joined: 18 May 2017
Posts: 743
Exclamation wrote:
MarkOZLAD wrote:
What type of sync are you using Exclamation?



Not sure - can test the lead later today, but it's just a cheap eBay cable not specified sync type - I did notice last night that if I disconnect the rgb lines I still get a real faint picture with no color and that goes away or gets blanked when I turn on osd - sounds like we can assume the cable I have is using composite sync and when I get c-sync retro-access cables in a couple weeks that will take care of it?

Edit: confirmed the cheapo eBay cables are wired with the sync plug connected to the composite pin, and also hooked up my SNES with composite cable and it also has a super dim b+w picture that blanks on osd - so yeah, looks like it will work normally when I'm not sending composite on top of rgb, yes?


I would be trying Luma or CSync for Sync. If they don't remove the issue will have to look harder at the TV schematic/service manual.
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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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 Post subject: Re: TV RGB mod thread
PostPosted: Fri Aug 14, 2020 11:53 pm 



Joined: 13 Aug 2020
Posts: 3
Hi everyone.

I've been lurking for a while and managed to successfully mod a Panasonic ct27d12df (with one major issue).

I followed all the directions and mux'd my RGB signal with the osd. I removed the factory terminating resistors, used 75ohm terminating resistors on my external signal, added in-line resistors based on the chart in MarkOZLAD's signature, placed sync on the component y, ran 5v to the blanking pin on the jungle and was met with a black screen. I could however see my image without sync on other inputs, once I changed to my input, it would go black.

I looked at the jungle's datasheet (TA1310BN ) and in the IC's block diagram I noticed that there was an rgb blanking flowchart item after the RGB mixer and it was controlled by the x-ray protection pins. The datasheet states that if these pins are unused, you can ground them to disable the function.

When I ground the pins, my image shows up. The picture is great, but a little overscanned on the horizontal.

Now, for obvious reasons, I don't like the idea of x-ray protection being disabled. I'm wondering if someone more experienced than I am could take a look at it and find a way for this to work while *not* disabling any protection or at least nudge me in the right direction for troubleshooting.

Thanks in advance.

diagram with notes: https://imgur.com/a/5RhJSnO
jungle block diagram: https://imgur.com/a/OCgQQ7K

jungle datasheet: https://drive.google.com/file/d/1RSESi6 ... sp=sharing
panasonic ct27d12df service manual: https://drive.google.com/file/d/1tzlfhQ ... sp=sharing


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 15, 2020 5:56 am 



Joined: 26 Jun 2019
Posts: 21
Would it be possible to modify samsung model CL21A551ML?
Grateful.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sat Aug 15, 2020 6:19 pm 



Joined: 26 Dec 2019
Posts: 3
BobWoggle wrote:
Got a couple free 20" sets the other day, Toshiba cf20e30 and JVC AV-20320.

Couldn't find service manuals or schematics for these sets nor datasheets (at least in english) for their jungle chips (toshiba ta1223n and ta1242n respectively).

Had to search all of the manuals of sets of this era, from either company, for the same jungle and a detailed enough schematic. Both take osd blanking and rgb through pins 14-17, should be a relatively easy mux.


did anyone figure out how to rgb mod a JVC AV-20320?


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 16, 2020 1:49 am 



Joined: 16 Aug 2020
Posts: 7
Hi gents, trying my hand at doing an RGB mod, picked up every small CRT i could find in my area, figured with some pratice one of them would work, first one i have on the bench service manual here, the IC seems to have no RGB IN only out, i would assume the the OSD stuff is all internal of the one IC and i cant RGB mod this set?

Thank for the help guys.


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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 16, 2020 5:09 am 



Joined: 18 May 2017
Posts: 743
zape wrote:
BobWoggle wrote:
Got a couple free 20" sets the other day, Toshiba cf20e30 and JVC AV-20320.

Couldn't find service manuals or schematics for these sets nor datasheets (at least in english) for their jungle chips (toshiba ta1223n and ta1242n respectively).

Had to search all of the manuals of sets of this era, from either company, for the same jungle and a detailed enough schematic. Both take osd blanking and rgb through pins 14-17, should be a relatively easy mux.


did anyone figure out how to rgb mod a JVC AV-20320?


Standard OSD Mux candidate. R738, 740 and 742 are the resistors to be removed to become the RGB injection point. R736 is the point for blanking.
_________________
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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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 Post subject: Re: TV RGB mod thread
PostPosted: Sun Aug 16, 2020 10:42 pm 



Joined: 13 Aug 2020
Posts: 3
Hey guys,

Long time lurker here.

I had a long post I submitted two days ago as my first post, but for some reason it never made it through the first post mod filter. Maybe because I had attached some pdf links to it or something. Let's try this again without any google drive links.

Anyway, I recently modded a Panasonic ct27d12df successfully with one major issue. It only works when I ground out (disable) the x-ray protection pins (pins 7 and 8... Hold down reference and Hold Down, respectively) on the jungle chip. If I don't do this all I get is a black screen. I obviously don't want to leave that protection disabled but I can't figure out why it's getting triggered.

I removed factory terminating resistors, added 75ohm terminating resitors, added in-line resistors per mark's spreadsheet, added 5v to Ym/Ys pin, sync to component sync. If I try to run the set with protection on once I change the input to my RGB input the screen goes black. If I change to another input I can see my RGB signal without sync.

Diagram of tv and a few select parts of the jungle datasheet:

https://imgur.com/a/6XTbl0R
https://imgur.com/a/oaW4nq9
https://imgur.com/a/LM81NQc

Anyone got any ideas?

Thanks


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 18, 2020 6:43 pm 



Joined: 26 Jun 2019
Posts: 21
How to rgb mod a SAMSUNG CL21A551ML?
Please


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 18, 2020 9:23 pm 


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Joined: 25 Mar 2009
Posts: 280
Location: USA
pyrojoe wrote:
Hey guys,

Long time lurker here.

I had a long post I submitted two days ago as my first post, but for some reason it never made it through the first post mod filter. Maybe because I had attached some pdf links to it or something. Let's try this again without any google drive links.

Anyway, I recently modded a Panasonic ct27d12df successfully with one major issue. It only works when I ground out (disable) the x-ray protection pins (pins 7 and 8... Hold down reference and Hold Down, respectively) on the jungle chip. If I don't do this all I get is a black screen. I obviously don't want to leave that protection disabled but I can't figure out why it's getting triggered.

I removed factory terminating resistors, added 75ohm terminating resitors, added in-line resistors per mark's spreadsheet, added 5v to Ym/Ys pin, sync to component sync. If I try to run the set with protection on once I change the input to my RGB input the screen goes black. If I change to another input I can see my RGB signal without sync.

Diagram of tv and a few select parts of the jungle datasheet:

https://imgur.com/a/6XTbl0R
https://imgur.com/a/oaW4nq9
https://imgur.com/a/LM81NQc

Anyone got any ideas?

Thanks



This is a long shot, but try changing your blanking voltage to 2.5v. you can do this easily by just using a voltage divider on the 5v with two 75R resistors.

According to the datasheet for that jungle, the blanking threshold is min 2.0v typ 2.25v max 2.5v. Maybe that pin doesn't like being fed 5 volts? I'm not sure what else to try honestly.


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 18, 2020 9:51 pm 



Joined: 26 Jun 2019
Posts: 21
How to rgb mod a SAMSUNG CL21A551ML?


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 Post subject: Re: TV RGB mod thread
PostPosted: Tue Aug 18, 2020 10:01 pm 



Joined: 13 Aug 2020
Posts: 3
Quote:
This is a long shot, but try changing your blanking voltage to 2.5v. you can do this easily by just using a voltage divider on the 5v with two 75R resistors.

According to the datasheet for that jungle, the blanking threshold is min 2.0v typ 2.25v max 2.5v. Maybe that pin doesn't like being fed 5 volts? I'm not sure what else to try honestly.


Thanks for the suggestion.

While testing everything I had a pot hooked up to the blanking line. It seemed like everything over 3.1v worked as far as blanking went.

You're probably right though, I might want to drop the voltage to what the chip expects.

All in all though this didn't matter if I didn't disable the x-ray pins.


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Aug 19, 2020 4:54 pm 



Joined: 16 Aug 2020
Posts: 7
Hello everyone, I've since my last post set the other CRT aside and start working on this RCA model E13320, i really like the look of this one, and looking at the schematics it looks promising.

So if I'm understanding right I need to:

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

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

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

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

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

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

service manual

schematic and pictures


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 Post subject: Re: TV RGB mod thread
PostPosted: Wed Aug 19, 2020 11:47 pm 


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Posts: 1335
Shiozaki wrote:

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

Nothing protects it, nothing needs to. It is a TTL output pin, seeing 5V won't do it any harm


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 Post subject: Re: TV RGB mod thread
PostPosted: Thu Aug 20, 2020 12:35 pm 



Joined: 16 Aug 2020
Posts: 7
maxtherabbit wrote:
Shiozaki wrote:

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

Nothing protects it, nothing needs to. It is a TTL output pin, seeing 5V won't do it any harm


8bit guys video i guess left an impression on me that it could cause damage.


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