TV RGB mod thread

[spikespiegel]

I do remember on mine,for the fast blanking there was 8v on that line by default,I just left it alone.

As for enabling component video it could very well be a different option but it's very different than a regular Philips's set.

I knew it! I knew it there was something wrong with the hardware itself! Lemme check one thing, I'll be right back.

[spikespiegel]

I do remember on mine,for the fast blanking there was 8v on that line by default,I just left it alone.

As for enabling component video it could very well be a different option but it's very different than a regular Philips's set.

Sorry mate, turned out I fell asleep and only now I'm having time to reply.
Look at this:


As you can see, my TV uses a Philips microcontroller (TDA 9381), same way as yours, so although it's a Panasonic TV, inside it's a Philips.

Also check this:




F Blank (pin 45) is where the blanking line is, if you look on the right corner you'll see 8 volts. As for that resistor in the middle of the path, if I remember well it doesn't even exist on the PCB. When I was modding this TV I've cut all the connections of the RGB, including the blanking line. Up until yesterday I was testing the mod using 5 volts, but earlier this morning I've soldered a wire to the pin 39 (8 volts) and I am using it now to feed the blanking line. I'm going to be home later in 3 hours, are you going to be online? I'll test the option bytes again when I get home.

[spikespiegel]

I do remember on mine,for the fast blanking there was 8v on that line by default,I just left it alone.

As for enabling component video it could very well be a different option but it's very different than a regular Philips's set.

I've been here for almost 1 hour trying. Still no success.

[spikespiegel]

I spent many hours altering the values in the CHK1 options and had no luck at all. On the other hand, I did manage to get in the memory menu, but I have no idea what to change there and I don't dare to do that without any documentation. So, from this information, can you shed me a light? I really wanted to see this TV rgb modded, its image is fantastic.

No, I can't offer a way to "make it work." It's totally possible that it's not doable without both doing some hardware modifications around the IC and setting something in the memory. Sometimes setting a particular mode could necessitate pulling a pin on an IC up or down (or more than one pin) or something like that. Without the all the datasheets, I'm flying just as blind as you are. Even then, I probably wouldn't mess with it unless I was really sure I could do it without doing any EEPROM programming or anything like that, and there would have to be clear and obvious remarks about enabling RGB.

I think I've burn't the IC blanking line... Pikkon said he didn't need to feed the blanking line, yesterday I noticed that my IC blanking line was also being fed by a 1.8 volts connection, and I was inserting 5 volts before, now 8 volts. Is there anything I could do to find out if I burn't it? Weird thing is that there's some voltage coming out of the RGB connectors, althought they are all isolate.

[vol.2]

I think I've burn't the IC blanking line... Pikkon said he didn't need to feed the blanking line, yesterday I noticed that my IC blanking line was also being fed by a 1.8 volts connection, and I was inserting 5 volts before, now 8 volts. Is there anything I could do to find out if I burn't it? Weird thing is that there's some voltage coming out of the RGB connectors, althought they are all isolate.

There should be some kind of signal related voltage on the RGB lines (nominally 1V pkpk), so that's nothing to worry about. IIRC, it's something like 350mV RMS, so it shouldn't be very high on a multimeter, but you can look at it on a scope if you're worried and check for any significant DC offset.

No way to "check" that I can think of other than pulling components out of circuit and testing them. There should be voltages called out in the schematics you can check, but make sure to read the SM carefully because those voltages are under certain conditions and by checking in a certain way; for example, with a SMPTE color bar signal displayed, you should see X volts peak to peak with your scope on a certain time base and a specific voltage range. You might have to use video triggering and add a little holdoff to get something like that to stop rolling though. (this is just an example of what you might see, each SM has it's own instructions)

Make sure you're performing any tests like this with the TV hooked up to an isolation transformer. You don't want to touch something by accident that's connected directly to the grid.

[cagnascimento]

Would anyone know if I can do the RGB MOD on the Philips 14PT314A. Below is the manual link.

https://www.electronica-pt.com/esquema/ ... e_vignette

[spikespiegel]

Would anyone know if I can do the RGB MOD on the Philips 14PT314A. Below is the manual link.

https://www.electronica-pt.com/esquema/ ... e_vignette

Se os pinos 32, 33 e 34 forem entradas, pode sim. Posta no meu grupo do WhatsApp depois o resultado. >:)

If the pins 32, 33 and 34 are inputs, sure you can. Post the results in my WhatsApp group later. >:)

[DeathByBFG]

Does anyone know if the Toshiba CF1327B can be modded? The jungle chip appears to be a TA8680BN. I couldn't find the manual for the TV. But I could find a datasheet for the jungle chip. This is an RF only set so I'm assuming not. But I figured I would ask before taking any other actions on it. Link to the datasheet below.

https://datasheetgo.com/ta8680bn-datash ... n%20shrink

[krimstah]

Help anyone ?

Hi

Can anyone please assist me if I can rgb this crt, mine doesn't have scart but according to the manual below it can possibly go in the teletext section.

Lg Crt Television Rt 29Fb50Rb

https://usermanual.wiki/Lg/LgCrtTelevis ... .762447995

If I'm using the sunthur board what resistors/caps do I need to buy?

Picture of the chasis I took , https://imgur.com/a/2GyYP3j

[spikespiegel]

Help anyone ?

Hi

Can anyone please assist me if I can rgb this crt, mine doesn't have scart but according to the manual below it can possibly go in the teletext section.

Lg Crt Television Rt 29Fb50Rb

https://usermanual.wiki/Lg/LgCrtTelevis ... .762447995

If I'm using the sunthur board what resistors/caps do I need to buy?

Picture of the chasis I took , https://imgur.com/a/2GyYP3j

IC01 could be RGB modded through the pins 20, 27 to 30. Through Option 2 Function you could enable SCART.

[spikespiegel]

Does anyone know if the Toshiba CF1327B can be modded? The jungle chip appears to be a TA8680BN. I couldn't find the manual for the TV. But I could find a datasheet for the jungle chip. This is an RF only set so I'm assuming not. But I figured I would ask before taking any other actions on it. Link to the datasheet below.

https://datasheetgo.com/ta8680bn-datash ... n%20shrink

I can barely see a thing in that datasheet. Optimize it using AI and share the pdf URL here.
Use an AI upscaler. You could try converting the IC page in the PDF to JPG and then use AI to optimize and upscale it.

[viletim]

I think I've burn't the IC blanking line... Pikkon said he didn't need to feed the blanking line, yesterday I noticed that my IC blanking line was also being fed by a 1.8 volts connection, and I was inserting 5 volts before, now 8 volts. Is there anything I could do to find out if I burn't it? Weird thing is that there's some voltage coming out of the RGB connectors, althought they are all isolate.

The datasheet says the fast insertion input threshold is < 0.4V for no insertion and > 0.9V for data insertion. Maximum 3.0V. See R678, R679 in the circuit diagram you showed? They form a potential divider that probably puts something halfway between 0.9 and 3.0 volts on the blanking input pin.

Does anyone know if the Toshiba CF1327B can be modded? The jungle chip appears to be a TA8680BN. I couldn't find the manual for the TV. But I could find a datasheet for the jungle chip. This is an RF only set so I'm assuming not. But I figured I would ask before taking any other actions on it. Link to the datasheet below.

It looks like pins 19 and 20 are for OSD input, but there are only two of them. Need three for RGB, so this not an RGB input, whatever it is.

[vol.2]

It looks like pins 19 and 20 are for OSD input, but there are only two of them. Need three for RGB, so this not an RGB input, whatever it is.

I've seen it where they just have Green and Red TTL inputs for the OSD so that it can make that slightly yellowy green that is typical.

[bclark219]

I successfully Mux modded an RCA F25442 if anyone else wants to mod one of these. The Jungle IC is a LA7612A. Chassis CTC203AD9
This is my first real electronics project. There is not any service manuals available online for this model so I had to figure everything out on my own. I'm surprised I was able to pull it off.




Solder the Left and Right audio wires to these spots labeled in the picture. Ignore the wires soldered in the picture. I took the picture when I was still trying to figure it out.
For some reason the speakers on the TV are wired backwards from the factory, So I soldered the Left to the Right, Vice versa. Also you need to have an RCA jack plugged into the audio input on the front to have the sound work. There is a switch in the connector that makes the audio go through.


I used trimmer pots to fine tune the RGB and blanking voltage.
I ended up setting the resistors to get the max color and contrast while sacrificing the color of the OSD. The OSD has a bit of a red hue now but it doesn't matter. still perfectly usable. The rest of the adjustments were made in the Service Menu.
I believe I set the trimmers to;

RED = 240 ohms
GREEN = 80 ohms
BLUE = 122 ohms
BLANKING = 28 ohms (3.7v)

SERVICE MENU SETTINGS (RGB adjustment)
P13 = 100
P14 = 73
P15 = 62

Spoiler

I followed this guide to wire my SCART connector.
https://crtdatabase.com/modding/wiring- ... -connector

[GK6475]

So, I did most of an RGB MUX mod on my Toshiba MD9DP1 and I can't seem to get blanking to work. I tried using 1100ohms inline and that did not work. I have the blanking signal with 1100 ohms of resistance connected after the 1k and 100 ohm resistors on the motherboard. Is there a more appropriate resistance value that I need to use, and should I connect the blanking line to a different location on the board? The jungle chip is an LA76319NM-MPB-E. Service manual: https://elektrotanya.com/toshiba_md9dp1 ... nload.html.

[Anonygoose]

Hey guys

I'm trying to RGB mod this Sony Wega Kv-ar25m80 with a Cxa2159s jungle.

I isolated the RGB and blanking inputs by removing the 3 caps and 1 resistor. Connected the RGB lines to 75ohm and .1uf caps and fed the blanking pin 5V.

Pretty confused as I'm not getting any display at all after doing this, not even osd. This should be a straightforward direct injection mod right? The pins I'm wiring to go to an unpopulated teletext connector.

Any ideas?

https://imgur.com/a/UpbGbzd

[Lizzardious]

Hey peoples!
I'm almost done modding an LG Flatron which I posted recently about here viewtopic.php?t=60010
Pretty old and specific thread though so I'll switch to here.
With much tinkering and head scratching, I've finally got RGB working on this board.
There were a bunch of jumpers that needed to be fitted, and the thing that really stumped me, a bunch of jumpers that needed to be removed (marked as resistors with specific values on the schemtatic). LG must have really wanted switching this to Scart to be difficult!

Seems to be working ok now, except the gamma response doesn't seem right. After about %50, things curve off to black too quickly.
No amount of FBT tweaking or service menu adjustments seems to alleviate the issue which brings me to the topic of load / impedance / terminating resistors. I must admit, I've never really got my head around impedance properly.

Firstly, could mis-matched impedance cause the gamma response to be off?

Diagnostics:
With the 75ohm resistors in place at the Scart connector position on the PCB, I wasn't getting anywhere close to 0.7Vpp at the jungle chip on the RGB lines. More like 0.2Vpp and with a bit of a spike on the edges of the square waves.
(Checking the data sheet for the VCT49xy, it is indeed looking for 0.7V at the RGB inputs)
So I removed the terminating resistors completely. Now I get full 0.7Vpp clean waveforms at the jungle chip and im not seeing noise or ghosting.
Measuring between one of those lines and ground I get ~0ohms so no sneaky load resistors elsewhere.

So should I maybe try add some higher value resistors there instead of 75ohm so there is at least some load?
Or should I just be thankful it all works as it is and try deal with perfecting the gamma in software?

I ended up just putting wire jumpers at L201, L204, L206, L206, R217, R218, R219.
I tried 75ohm resistors at R203, R204, R205, R213 which grounded most of the signal so removed them completey.



My source is MisterFPGA board VGA port which I assume should be standard 75ohm, but I have no idea how to test it.

Ok this guy is in full working order. TL;DR I tweaked the terminating resistors and added missing caps at the jungle and it was happy days.

For anyone winding up here on a journey with an LG, I figure I'll make note of what had to be done, and what I learned along the way.

Firstly, the terminating resistors were pulling down the voltage too much. I also couldn't quite understand their function and why it the image looked better without them.

As I understand it now (after a long chat with ChatGPT), if the signals only have one path to follow to ground through the IC, some of the signal can reflect back on the lines and create ghosting and interence. Something like a channel of water hitting a big turbine that can't instantly start to turn. Some of the water bounces off the blades backwards and created turbulence.
By splitting the signal and creating a second path to ground, this can relieve some pressure and smooth out the flow. In the case of 75ohm resistors, it's roughly splitting the signal In half.
But now we have half signal doing work, and half going directly ground. That means to get 0.7Vpp at the chip, we now need twice as much at the source, or about 1.4V with cable disconnected.

In my case, I was only measuring ~0.84Vpp with the cable disconnected. Not enough for 75ohms. So the easiest fix in my head was change the resistors. Indeed, placing 390ohm resistors at the Scart position instead of 75ohm gave me 0.7pp at the chip.

Later I realised what the resistors marked with a star were on the schematic! They create a voltage divider with the terminating resistors and their value would be calculated to get the voltage to 0.7Vpp. In my case I should have kept the 75ohm resistors at R203, R204, R205, R213, and put 3k9 resistors in mystery positions R19,R218,R217 where I put jumpers.

A bunch of other jumpers (marked on schematic) had to be put in place to get the RGB & FB lines before I was getting the proper 0.7Vpp waveforms at the jungle, but even with them in place I still wasn't getting a picture, no matter what voltage was applied to the FBIN(78) pin. Then I saw the problem! LG had a jumper to ground at the R525 position which should be 1.2K. I removed that jumper and bam! Picture.

Now it was all working great, but there was something up with the luminance values. There was no dark greys, things seemed to clip off to black at about %33. No amount of service menu tweaking could correct it. Then I noticed the last issue. LG had also put jumpers at the cap positions at the jungle (C515, C516, C518). Once I put the correct 0.1uf caps there it was golden.

If someone could help complete my understanding here it would be great. I would have thought those caps decoupling caps, removing the DC component from the signal. But the chip expects 0.0 - 0.7V which is the same DC range as the VGA cable no?

Hey, I know it's a kinda old post, but doesn't that IC Interlace the signal on your TV? I've got a Flatron with that chip and it Interlaces the progressive signal from every input. Or could a Jungle chip be totally differently configured depending on the set?