TV RGB mod thread

[qjkxbmwvz]

Just inject your signals straight onto the RGB out pins of the main IC

No, you don't understand: that's what I'm doing, and it does give me an image (dark, of course), but I'm also getting retrace lines. The 20PT6245/37 has a very simple connection between jungle and neck: a single resistor on each line. That's it. I could inject to the jungle side of the resistors or to the neck side or, what's the same thing, to the RGB pins on the neck itself. What I've found is that I need to go through resistors before the neck or the TV will shut off. Right now, I'm just going in through the existing resistors, but I get retrace lines. What do I need to do to fix that? Use my own resistors further up? Throw in some diodes?

I notice that you're not using terminating resistors or coupling caps, but I can't get away with that! My set just shuts off on me if I don't include both. If I could leave out the resistors, that would solve my retrace line issue, but I can't do that. Without the resistors, it shuts off after a few minutes; without the capacitors, it shuts off after a few seconds.

[VajSkids Consoles]

No 75 to ground terminating resistors. That would kill the signal on this tv and divide it down to too weak of a signal. I haven’t used them in any of my hacks. The consoles all generally have a 75r in series and caps where needed which is normal. You wouldn’t have caps in the console or console cable then more in the set...

I don’t get why you’re having issues... when I get retrace lines I just adjust the power to the tube on the flyback knob. Use a black screen. You just twist it super gently and just back far enough that you have no lines/interference and the screens pure black. You want to have this set so you have crystal clear RGB and the other inputs are still fine as well. My initial hack this needed to be adjusted between consoles but that’s because I was using my own RGB circuit that wasn’t attenuated correctly at the time- sort of at a halfway point so it worked on multiple consoles.

Usually you can have a win with this flyback setting but not always geometry which has nothing to do with RGB hacking anyway. I.e I often use overscan on my PVM for pal to stretch full screen and sometimes underscan on 60hz because it cuts the the top right corner off. I am not going to adjust geometry to suit one console.

[VajSkids Consoles]

Just remembered the tubes are set up to shut down if you over drive them... if you adjust the flyback too rapidly it will power down. Just be gentle. You’ll be turning yours down

[Harrumph]

Rather than creating a new post I was wondering if anybody knows of a device that can force 4:3 aspect ratio on a 1080P monitor that doesnt have that function built into it? I am having issues whereby naomi 31k is displaying at 16:9 on my viewlix diamond black monitor. Apparently Taito has said that the diamond black monitor doesnt have 4:3 which other viewlix does support. What are my options?

Ask here instead: viewtopic.php?f=6&t=34857

[VajSkids Consoles]

Anyone trying the Method mentioned- just be aware the encoder in a TV is like the encoder in a console running backwards

The console (some of them) will take RGB signal into encoder and then “pack” this together, almost like a zip file containing all the video information.

This “zip file” goes into the tv (composite) and the encoder then “unzips” it and delivers again the pure R G B signals to the tube. Because the method of driving guns directly is purely a hack it doesn’t follow conventional video rules/ standards you’d find on a television designed with legitimate RGBs in mind.

If we stick 75ohm terminating resistors on the RGB outputs leading to the tube EVERTHING going to the tube now has those resistors working as dividers. Composite / S video/ analogue

Everything heading to the tube

If you have issues legitimately hacking a CRT - as In
Some models have SCART Overseas and it’s simply
Missing on the US/ Australia models and we are just adding what was skipped at factory

If no

Then I definitely recommend just smashing it onto the output lines.
My sharp would only show RGB of my consoles
Through the OSD text initially and I was like stuff this !

I am only chipping in my 5 cents because I’ve had RGB show up
Perfectly on the tellies Ive opened within the first hour

Basically if you have RGB lines heading to the tube you can simply inject your RGB somewhere into these lines at an appropriate level.

Too weak / boost at flyback
Too strong / horizontal lines - reduce at flyback

Sync on green works in you have component already and want to use that channel (DVD channel on Sony Trinitron)

to the people
Smart enough to pull off proper RGBs and retain full OSD functionality for the input on a telly that never had RGBs in mind- my hat is off to you

[Virtual Davey]

"If we stick 75ohm terminating resistors on the RGB outputs leading to the tube EVERTHING going to the tube now has those resistors working as dividers. Composite / S video/ analogue

Everything heading to the tube"

Would that explain why, even though I now have a great RGB picture on my CRT after modding, the other inputs on the TV (RF, composite) no longer display as well as they did before the mod?

[VajSkids Consoles]

Don’t know how you’ve hacked it. Everyone does it differently.
If you have used this method you’ve got the wiring from the scart head to the Tube there so unless you’re using RGB you’d have to unplug the SCART cable when not in use or it causes interference on everything else

*n yeah everything going to the tube uses these tracks so you’d be ultimately adding a 75ohm to ground on anything on its way to the tube

[laikmike]

I was able to successfully mod my Sony Trinitron KV-27S42 using MarkOZLAD's OSD method. It's definitely a lot easier (and less nerve racking) than trying to snip the OSD lines and bend the pins up, I wish I'd have gone this route initially - but I learned quite a bit along the way.

Album of the process: https://imgur.com/a/TVU4Qe2

I basically followed the BA-4D chassis instructions Mark wrote up, but when I powered up the TV to test it out I was getting a black screen and could only see anything when the OSD was visible on screen.

Fortunately I saw Tengugurl's post from a couple weeks ago that provided an easy fix for the exact same model - removing the 1k resistor off and using pin 49 and a different 5v source solved the problem completely. Here's a video showing a few seconds of Sonic 2 running on an emulator (using CRT EmuDriver off an AMD Rademon HD 7950 using VGA to BNC cables)

Edit: Link to the video since I can't inline it: https://i.imgur.com/XQY2Ieb.mp4

I had to tweak CRT EmuDriver a bit to get this working - it mentions tweaking the sync polarity for older cares when you enable composite sync - but I had to do this for my HD 7950 as well. Once I set both values to 1 in the monitor.ini everything worked perfectly. I need to adjust the picture position and check geometry still, but it looks great so far!

Thank you MarkOZLAD for the excellent write up and instructions, and thanks to Tengugurl for the fix as well!

Hello everyone need some help, maybe this has been ask like thousand of times but i searched a lot and did not found a solution for my Sony, the chasis is a BA-4D from 1999 is a little different from the ones i’ve see in other post here in the thread, i follow the instructions of the quote post also look in to Marks BA5D and BA4D, here is a picture of how I set up all
https://m.imgur.com/gallery/fbyZlOy
Maybe im doing something wrong, i just barely see something when i turn it on and pull up the 5v switch, im hooking up a ps2 with rgb (sync on luma) (maybe thats the problem?) hope you can help me!


Edit: here is the manual https://www.manualslib.com/download/699 ... 13m42.html

[Osirus]

Maybe im doing something wrong, i just barely see something when i turn it on and pull up the 5v switch, im hooking up a ps2 with rgb (sync on luma) (maybe thats the problem?) hope you can help me!

PS2 only does RGsB or YPbPr so it doesn't sound like you're getting any sync input to your TV. The G input on the jungle is for Green signal only, it won't do anything with sync.

[qjkxbmwvz]

Maybe im doing something wrong, i just barely see something when i turn it on and pull up the 5v switch, im hooking up a ps2 with rgb (sync on luma) (maybe thats the problem?) hope you can help me!

PS2 only does RGsB or YPbPr so it doesn't sound like you're getting any sync input to your TV. The G input on the jungle is for Green signal only, it won't do anything with sync.

The PS2 does RGsB in 480p, which it's rarely in. In 480i/240p, it uses a separate sync, either composite or luma.

Now, as to the mod, forgive me if I'm interpreting this wrong, but it looks as if the sync signal from the console is being connected to 5V - oughtn't it to be fed into one of the stock input lines?

[laikmike]

Maybe im doing something wrong, i just barely see something when i turn it on and pull up the 5v switch, im hooking up a ps2 with rgb (sync on luma) (maybe thats the problem?) hope you can help me!

PS2 only does RGsB or YPbPr so it doesn't sound like you're getting any sync input to your TV. The G input on the jungle is for Green signal only, it won't do anything with sync.

The PS2 does RGsB in 480p, which it's rarely in. In 480i/240p, it uses a separate sync, either composite or luma.

Now, as to the mod, forgive me if I'm interpreting this wrong, but it looks as if the sync signal from the console is being connected to 5V - oughtn't it to be fed into one of the stock input lines?

Yeah, thats the way i hook up to 5v just like it looks on the picture, maybe thats why im not getting sync, i will hook it up to OSDBLK to ext sync and see if that fix my problem, thanks i didnt notice that mistake, and about the sync on luma, should it work? O I need Composite sync?

[qjkxbmwvz]

Now, as to the mod, forgive me if I'm interpreting this wrong, but it looks as if the sync signal from the console is being connected to 5V - oughtn't it to be fed into one of the stock input lines?

Yeah, thats the way i hook up to 5v just like it looks on the picture, maybe thats why im not getting sync, i will hook it up to OSDBLK to ext sync and see if that fix my problem, thanks i didnt notice that mistake, and about the sync on luma, should it work? O I need Composite sync?

Your TV shouldn't care whether you give it composite, luma (from S-video or component), or a clean c-sync. If you were working with an Amiga monitor or something like that, you would need to throw in an LM1881; for a TV, you should be able to just wire it straight into a composite input or whatever - just make sure to switch the TV over to the input that you use, or your picture won't hold still. Your sync line could (in this case does) carry a full image in it, but you're using fastblank to cover it up. (If you're using SCART, pin 16 should have 5V for this.) The input that you wire into should already have termination, coupling, etc., so you don't need to worry about that.

[laikmike]

Now, as to the mod, forgive me if I'm interpreting this wrong, but it looks as if the sync signal from the console is being connected to 5V - oughtn't it to be fed into one of the stock input lines?

Yeah, thats the way i hook up to 5v just like it looks on the picture, maybe thats why im not getting sync, i will hook it up to OSDBLK to ext sync and see if that fix my problem, thanks i didnt notice that mistake, and about the sync on luma, should it work? O I need Composite sync?

Your TV shouldn't care whether you give it composite, luma (from S-video or component), or a clean c-sync. If you were working with an Amiga monitor or something like that, you would need to throw in an LM1881; for a TV, you should be able to just wire it straight into a composite input or whatever - just make sure to switch the TV over to the input that you use, or your picture won't hold still. Your sync line could (in this case does) carry a full image in it, but you're using fastblank to cover it up. (If you're using SCART, pin 16 should have 5V for this.) The input that you wire into should already have termination, coupling, etc., so you don't need to worry about that.

Thanks for the help, actually is a component cable with composite on it so I use (Y Pb Pr) and composite for sync, I removed the 1KR and i just barely see something but sometimes just go black and sometimes the tv turns off, then I reconnect the OSDBLK to the Ext sync (BNC) to the switch and the 5V that im taking from C039 but nothing happens just the same problem

[labrat]

This is a repost combining my "first posts" that feel like they have been buried during the "waiting for approval phase".
I'm trying to understand the connections between the micro to a TB1238AN. (which I believe should be 0.5Vp-p). On my unit here, and in multiple schematics from the web, the micro passes through a 1K resistor inline, with a 1.2K (or 1.5k) to GND (voltage divider?), branching through a capacitor to the Jungle. (the standard OSDMux format, but the resistance values don't make sense to me). For a typicaly 5V output from the micro, this doesn't create a 0-0.5V level shift. Which I *thought* was the target goal of the voltage divider.

Can anyone elaborate on this?

The second area I'm stlill struggling to follow is when using the pre-calculated MUX tables, I can replace the 1.2K with a 75:60 ohm pair, but to get close to 0.5V predicted measurement the spreadsheet tool (vs tables) indicates a 37ohm would be a closer/better choice. So my understanding seems flawed. Pls feel free to direct me to other resources/posts (or "this came up in this thread last <fill in the approx month>") .. and I will search them out.

My experimental device (first time effort) is based on the TB1238, but is a no-name brand with no-sign of service manual available on the web. (13" tube with abuilt in DVD player). It's all through hole components and relatively easy to trace. I wasn't sure if this should be "yet another entry in this thread" with photos etc etc. Or should I be starting a new thread (similar to what MarkOZLAD did for the TEAC CT-M5122H)? This TV has some extra logic beyond the default boiler plate designs.

Thx.. and thanks to all those who take the time to watch/answer in these forums.

[Romariu]

Can I inject the RGB signal directly into the PCB where it is marked JS650, JS651, JS652 and JS653 Panasonic TC14A10 or do I need to remove some resistor?
Please help me I am confused here is the link scheme.
Thank you

https://www.electronica-pt.com/esquema/ ... x5y-22402/

[MarkOZLAD]

Can I inject the RGB signal directly into the PCB where it is marked JS650, JS651, JS652 and JS653 Panasonic TC14A10 or do I need to remove some resistor?
Please help me I am confused here is the link scheme.
Thank you

https://www.electronica-pt.com/esquema/ ... x5y-22402/

It's an OSD mux mod.

R650, R651, R652 to be removed. Use mux resistor values anywhere from 820R to 1000R.

Should be an empty chip header E9 to use to input your RGB.

[Romariu]

After removing the 3 resistors I sold the other 3 of different value and that ?

[MarkOZLAD]

After removing the 3 resistors I sold the other 3 of different value and that ?

You have to remove the resistors and then implement the OSD mux circuit. I suggest the E9 header as a place to do this.

[labrat]

Second OSDMux attempt. Pulled the default 820ohm and replaced with 1K + 75 ohm voltage divider.
Target use as an arcade cabinet replacement. Planned to trial and error inline resistors, but this is what I saw on the first boot/start attempt.

The image, however, appears to be slightly too large, and no physical knobs to tweak image width and height.
What would be the typical way to address this? Parts to replace on the board? Or is this something that finding the correct configuraiton parameter in the EEPROM might cover (there's only 512 bytes in there.. how hard could it be?)

[MarkOZLAD]

Looks good.

What model TV?

If there are no pots on the chassis for geometry there'll likely be a service menu....Accessing it can be tricky depending on model.

[labrat]

White-Westinghouse : TV-1906

(Couldn't find any schematic, but was able to trace out the circuit fairly easily.)

Processor Onkyo A8700
Jungle TA1268N

Resistors were SMD on the bottom of the board, but were dual foot-printed for through hole. So after cleaning out the solder, I could use through hole resistors from the top.

C-SYNC connected to the center pin of the incoming video connector.
---
Observations:

• Image is a bit large with clipping at the edges.

• Green "VIDEO" Text appears on start-up.. but does eventually timeout

• Default menu (I have the remote) offers control for BRIGHTNESS, CONTRAST, etc.. which have no effect on the RGB output

• When 'video input' is not selected, image won't sync (not surprising, as sync would be from the non-existent RF input)

• There is a 512 byte I2C EEPROM connected to the micro.

[MarkOZLAD]

If you wanted full control you could do an I2C hack.

skum has done one to this chip. Look up JVC RGB mod I2C.

[Osirus]

snip.

Hey Osirus, I have a extremely similar tv, could you please share the final schematic of what you did to get the RGb working?

I'm sorry I didn't see this reply until now.

I never did get RGB working on the Panasonic. As far as I could tell it was Digital RGB only. I ended up taking the TV to a thrift store.

[labrat]

On to my third television, only this one doesn't appear to have a jungle chip, opting instead for discrete components to control the OSD and blanking. (if I'm understanding it correctly)

Make/Model: Samsung CT-5072XVC
Chassis: CKA5OHM
(or so the label on the back of the monitor claims)

The PCB doesn't match 100% the partial schematic linked above. There is no IC902 (Closed Caption), and I haven't located the resistors that pull the OSD RGB lines to GND on this chassis (yet) (RC22-R25).

I'm theorizing that if I *could* find them (RC22-RC25), that I could swap them for a default setup with 75ohm divider.
But as there is no jungle, I thought to check here first (in case someone has tried this path already).

Edit: Adding a couple of pics.. as I'm not seeing any voltage divider as part of the OSD output (contrary to the schematic)

• a. captured schematic

• b. Photo with trace of the OSD RGB and BLANK connections.

Edit2: Missing from diagram -- Zener diodes as voltage clamps on the RGB OSD lines. Based on this, I would think this an excellent candidate for an Arcade monitor as we can wire in directly at the inline resistors on the RGB OSD line.

[Xpander]

Hi I’m new to the forums.

I was looking into rgb mod for this for a Sony Trinitron KV-32S40. I have the service manual it’s here.

https://www.dropbox.com/pri/get/sony_kv ... EJRbHx75DQ

[Xpander]

Found the data sheet for my Sony.

http://pdf.datasheetcatalog.com/datashe ... 801857.pdf

It looks like the junglechip(CXA2025AS) has analong rgb.

Video signal I/Os: Y/C separation input, Y/color
difference input, analog RGB input and RGB
output

[labrat]

That last one started well, made the mods, and demonstrated "blanking" capability. However even without anything attached I could tell it was trying to SYNC to the RF and not the incoming COMP SYNC. As there was not "video/input" button on the front of the set, I started looking at how to hard wire the "VIDEO" mode. Something went amiss the next time I pulled the PCB, and it's not longer starting up at all (even after I reverted the change). Found that Q902 had been running very hot, and lifted pads from the board. Repaired, added a heat sink, and still no signs of life. I'm nervous about probing inside the open/running chassis, so I may have to abandon this set and look for another.
Shame was I was hoping for a hat-trick on my first three conversions.

[maxtherabbit]

Should have just grabbed a universal remote mate

[labrat]

@maxtherabbit - I considered it, but as I was hoping to stuff this into an arcade cabinet, the hard wired for VIDEO thoughput seemed a better choice. I think the added flexing of the board has highlighted additional cold solder joints, or possible blown a fuse (not the main one). Still studying the schematic and coming up with a plan. Currently it sits completely dead. Not even a spark when go to discharge the tube, so it would seem that NOTHING has powered up at all. (no sound of relay, or degaussing etc etc) ( I did double check the power bar )

[Osirus]

Mod Log

TV: Sony KV-32S66
Chassis: AA-2D
Method: OSD Mix

Several people have done this chassis before, and I did my mod based on what was posted here. This chassis has a Micon that outputs the OSD signal as Digital RGBI and then converts it to Analog RGB before going into the Jungle IC. R1123, R1128, and R133 were the grounding resistors for this circuit and were removed. This particular board was quite easy to inject RGB into as it has 2 unpopulated connector pads CN1801 and CN1802 with 4 pins each that are tied together with 0 ohm resistors. The 4 pins are for R, G, B and Ys. I injected the RGB into the pins of CN1801 with 75 ohm ground terminations and 330 ohm series resistors. For blanking I removed JR1801 from the board which was connecting the Ys blanking line between the 2 connectors on the board. I soldered a 470 ohm resistor to the 5V rail and ran it to a DPDT switch along with the Ys output from CN1801. The output terminal of the DPDT was ran to CN1802 for blanking input into the Jungle. This enables the switch to swap between RGB and normal operation.

I connected composite sync to the Y pin of the S-Video input and ran the connector sense switch of the S-Video connector to the other poles of the DPDT so that when the switch is set to RGB mode it pulls R233 to ground and uses the Y signal from S-Video instead of composite. This means I don't get a leftward shift when in RGB mode.

Other notes: The video inputs for this TV are all on a daughterboard called the UV board. It was easy to disassemble the chassis and work on this board on its own. The schematic shows video inputs on the main A board but they were all unpopulated on my TV.