How to RGB Mod a Consumer CRT TV: The Battle Against the Panasonic TC29FX32L and the Micronas Microcontroller
Leia este artigo em português do Brasil: Como fazer Mod RGB em TV de Tubo: Guerra contra a Panasonic TC29FX32L e o chip Micronas
For a long (a really, really long time), I waited for the chance to buy a Sony Wega TV. But whether on Marketplace, OLX, or any corner of the internet, all I could find were Toshiba, LG, CCE (a national brand), Philips, Philco, Gradiente (another national brand, but one that has some JVC sets nationalized), or some lesser-known CRT brands (yes, CRT TVs). My goal was to buy a TV to modify it to accept an external RGB signal.
For those who are unfamiliar, a RGB mod is a method that is about connecting an external RGB signal (a pure video signal from, for example, a videogame console) directly to the TV’s microcontroller or even directly to the CRT through the neckboard (a PCB that comes connected to the CRT).
The purpose of this mod is to get the TV to display the best picture possible. Most of you reading this have probably never seen a CRT at its full potential, especially if you’ve only played videogames using composite video cables(the classic yellow and white Audio and Video cables).
In an RGB mod, you’ll get such a clean image — exceptionally clean — that not even the TV’s component video signal (if it has one) could produce such picture with perfect quality. Technically speaking, the YUV signal (component video, YPbPr) does offer more colors than the RGB signal, however, when something is connected to a TV via component video, the image comes out a bit “dirty,” although it’s still better than composite or S-video.
Back to the main topic: over time (over several months), I managed to find a few Sony TVs for sale, but the sellers were extremely greedy. One, in particular, was asking 500 BRL for a 29" Sony Wega, and he was the most difficult to deal with of all. He refused to lower the price, and when I asked for pictures of the TV’s model, he sent me blurry images. I asked him for clearer picture, and he almost cursed me out (yes, really). The guy was, for lack of a better term, a nightmare to deal with.
Months after I started searching for a Sony, I came across a Panasonic. I did some research on YouTube, and even through the video, I could see the picture quality was unreal. That’s when I “gave up” (or took a break from) on the Sony Wega. I went ahead and bought the Panasonic CRT for a reasonable price, 100 BRL. However, when I arrived to pick it up, the seller’s wife was reluctant and didn’t want to sell it for that price, but in the end, they agreed.
The purchase itself was a torment though, because they made everything difficult. I had to carry the TV down five flights of stairs with the former owner (for some reason, the building didn’t have an elevator). The guy was in such a rush when helping me carry the TV down downstairs, that it looked like he wanted it to fall and break.
Dear reader, understand this: I had been negotiating the TV for days and had already confirmed that I was going to buy the TV. The least they could’ve done was to bring it downstairs when I said I was on my way. But no. In addition to dealing with a grumpy woman and lugging something heavier than your mom (okay, just kidding), another issue arose. The seller had promised me he’d find someone to transport it (I had even offered to pay), but suddenly, it was up to me to find someone to help transport it and it didn’t work.
Turned out the seller ended up calling his boss, and oh boy, from the moment his boss arrived to drive us halfway, it was nonstop complaints. He was angry because the TV owner hadn’t gone to work yet, and I could tell the comments were indirectly aimed at me. His boss even had the nerve to say, “He was late because he was testing that TV” (who buys used stuff without testing them?). He was also upset about the TV being sold for “such a low price” (though that part seemed like an exaggeration), that claimed that the seller could’ve given it to him to use at his country house for watching soccer games. And on top of all that, he was mad because the TV’s owner owed him money.
This is the short version, but if I had to tell the whole story, Jesus… I left out a few details about other inconveniences that happened that day, including the seller’s wife asking if I could pay and wait for them to deliver the TV the next day — plus some drama involving someone else. That day, I had to deal with at least three different types of “severe mental disorders” because, honestly, the TV is really great. I’d even go as far as to say the picture is better than the Sony Wega (Sony addicts, don’t kill me, that’s just my opinion).
The TV not only has a much higher contrast than a Sony Wega (far greater than a Toshiba A-series) but it also have a very sharp and clear image. The picture is shaped in such a way that, from a certain distance, it almost looks like an LCD monitor, even though it’s only 240p. This is partly because it doesn’t have thick scanlines like the Sony Wega. It reminds me more of an arcade monitor than a regular consumer CRT TV.
Hands-on, it’s time to modify the circuit for inputting the RGB video signal. :)
RGB modding the Panasonic TC29FX32L consumer CRT TV
Before we get started, I must emphasize that this procedure should only be carried out by an electronics technician or someone who knows exactly what THE HELL they are doing. Seriously, this process involves handling high-voltage circuits and a Cathode Ray Tube (CRT) that operates similarly to an X-ray machine, with voltages ranging from 1 volt to over 30,000 volts. It is MANDATORY to safely discharge the CRT before touching anything in the circuit and on/in the CRT, and you must also discharge the capacitors on the circuit board. All this must be done with the TV turned off and UNPLUGGED from the power outlet, this means zero voltage, even if the TV is turned off. Do not attempt this if you are unsure of what you’re doing — don’t take the risk. I (the author) take no responsibility for anything you do with your device or your safety; all responsibility for your actions is entirely YOURS. Consider yourself warned.
According to the service manual, it is possible to RGB mod this TV via the Jungle IC (Jungle Chip, OSD). However, to my misfortune and, of course, my luck, this TV has a Micronas chip, as the creator of the Muxing method informed me. My misfortune is that none of the tutorials I found mentioned the Micronas chip, but my luck is that this chip is an all-in-one, so this mod eliminates the need for a 4PDT switch, which is required for various TV mods with two ICs (Jungle and Microcontroller). In these other scenarios, the OSD menu disappears after the modification if the TV only has one RGB-IN (some will come with an extra RGB input on the jungle chip, RGB-2), which is why the 4PDT switch is used.
It was a relief when the creator of the Muxing method told me, “You need to check if the RGB is not disabled” (because if it is disabled, there is a high chance the manufacturer has permanently disabled it), and concluded with “when I did an RGB mod on a Micronas chip, I still had issues with Wonky Images,” which is a term he used. “Wonky”, it basically means “distorted images.” After all that trouble with those crazy people (the old TV owners), I was still uncertain whether or not RGB modding this TV would work. However, since I had already gone through so much, I decided to keep going.
I consulted with several people from the Telegram group I was part of, folks from Discord, and online forums — most of them foreigners. Here’s a tip: it’s best when you know a lot of people before needing help with something, because, nowadays, people aren’t very friendly when asked for assistance. We live in an era of “leechers,” and it’s better to seek help from people in first-world countries, as there are usually more people willing to assist. Third-world countries (like the one that I’m from) have more greedy and selfish individuals per square meter than first-world countries. There’s also an interesting phenomenon I’ve only seen in first-world countries: in online communities, people start competing to provide the best answers. I’ve never seen this in Brazilian communities (Yeah, that’s my homeland). When dealing with greedy people, it’s best to adopt a passive role, simply answering questions or providing updates. I’ve seen many interesting things come out of these discussions, including alternatives I hadn’t considered before.
I have managed to open the TV and do what needed to be done, but this specific model has a significant issue: the main circuit is very cramped. I’ve tried about three different soldering methods and am still not satisfied with the result, although it worked. I had to solder directly to the microcontroller connectors because attempting to solder to the traces almost broke them. I plan to use a different method the next time I open this TV model.
Next is where the RGB signal is connected. Note that this TV does not require a 4PDT switch to activate and deactivate the external RGB (which is used by most people doing this mod); a standard on/off switch will be enough.
The blue-dotted areas indicate where you should solder. I recommend soldering directly to the IC pins, either on top or below the board — it doesn’t matter — but be careful not to solder two pins together as the circuit is very tight. The red-dotted areas are jumpers that need to be removed. Usually, jumpers are metal vias that can be cut with pliers, but in this TV, they are zero OHM resistors, so they need to be removed with an iron below the board. Be careful not to damage the trace. I use a 50-watt soldering iron, which is hot enough for any non-industrial soldering work and suitable for hobbyists. However, it’s also hot enough to destroy a circuit board, so if you’re using anything above 30 watts, be EXTRA careful.
Schematic and Complete Service Manual for the Panasonic TC-29FX32L
You’ll need the service manual to continue the process but keep in mind that this is a Brazilian set, so you’ll have to find a service manual CHASSIS GP41N SM, here’s the Brazilian service manual though:
Download Panasonic TC-29FX32L CRT TV Service Manual
Instructions on the Pinout for the RGB Mod
Do not execute this procedure just yet. First, read the information below and then execute the RGB Mod diagram.
Information about the TV Circuit:
1 – GND, pin 88: This is where the circuit should be grounded. In this case, you could also ground it via composite video, component, and audio inputs at the back of the TV, just solder a wire to their metal parts, or somewhere else on the board.
2 – VSUP5.0BE, pin 87: This is where the circuit’s power supply comes from, outputting exactly 5 volts. You’ll need to connect these 5 volts to the ON/OFF switch, then to the RGB circuit, and finally to FBIN, pin 78. Note that this will only work after the RGB is activated via software (this will be explained later in this article).
3 – RIN, pin 77; GIN, pin 76; and BIN, pin 75: These are the RGB terminals of the circuit—red, green, and blue, respectively. This is where the 15kHz, 240p signal from your external device (console, Raspberry Pi, PC, etc.) will be inserted.
RGB Mod Diagram:
Instructions:
FB 5V is the 5V power supply coming from VSUP5.0BE, pin 87, and going to FBIN, pin 78, which is where the circuit is powered. However, it first passes through a 100R resistor in series and then goes through a 1.2K resistor in parallel (which is grounded) before entering FBIN. For the RGB inputs, to each input a 0.1μF ceramic capacitor should be soldered in series. I recommend keeping the RGB wires’ 75-ohm resistors outside of the TV, as I did; look at this image:
I've organized things better now, placing the resistors inside a dental floss box along with the female VGA connector (HD15 female connector). But do pay close attention to the diagram, as these resistors should be connected in parallel and grounded. In my case, the sync part is handled externally. Notice the white plug in the image (I didn’t have a yellow one). The wire coming from the plug goes directly to the sync, where the vertical and horizontal VGA pins are combined and connected in series with two components in parallel: a 1N4148 diode and an R820 resistor. If you test only the sync, without activating the RGB, you should get a white image with a definition, like this:
If you get a white embossed image (like the one displayed), this means the sync is working. If you get a completely pitch-black image with no definition at all, then reverse the diode. In my case, it only worked by inverting the position of the diode—so, I've used the diode in the opposite direction of what’s shown in the diagram. Reverse the cathode and anode if you encounter any problems.
Inside the TV, I only left the 5-volt power resistors and the RGB capacitors. Keeping the rest outside makes it easier to test the RGB and sync signals.
Version 1.0
As I mentioned way earlier in this article, I'm still not fully satisfied with the mod. I plan to redo the soldering to make it aesthetically better and more organized. But for now, here's how I did it:
Steady now…
The Jumpers That Must Be Removed:
This is the conventional mod most people will do, by using a 4PDT switch. However, we’re not going to be using this mod here (although it’s nearly the same):
If you want to try the RGB mod via muxing, check out this other article.
RGB Mod for Panasonic 29FX32L – Update #1
Version 1.0
RGB Mod for Panasonic 29FX32L – Update #2
Version 1.1
For the mod box, I used a PS2 controller plug that was from a PS2-to-PC controller adapter. The wiring was done with jumpers. This makes it easier to handle everything externally since there’s no need to mess with the ceramic capacitors.
Version 1.2 (In Progress)
I don’t have a printer right now and don’t want to manually create the PCB, but I plan to design a PCB and make the diagram, schematic, and parts list available here. I could share the project files now, but my Windows is messed up. I’m backing up everything up to re-format, and it's the only system where the PCB software works (I couldn’t get it to run on Linux).
The Cherry on Top: Activating the RGB Mod
Doing the RGB mod on this TV isn’t enough—you also need to activate the external RGB feature (remember when that dude told me the RGB might be disabled?). Well, I had to access the service menu, which was another tricky part since the websites where I found the information explained it in a very shallow way.
Now, I’ll clearly and concisely explain how to access the service menu of the Panasonic 29FX32L:
Lower the TV volume down to zero. Then press the "sleep" button on the remote control (15, 30, 90 minutes—any value). Now, hold the volume down (-) button on the TV and, at the same time, press the recall button on the remote. This will open the service menu. Press 1 and 2 to navigate between the 3 service menus, then navigate to menu 2. The first menu is the PAL image system, the second is “memory options”, and the third is the NTSC image system.
Now, I’ll explain how to activate the RGB on the Panasonic 29FX32L (this also works for similar models, even if they are different sizes, as long as they have the same chassis):
In the second menu, navigate to Option 6 using keys 3 and 4. In the sequence from 7 to 0 (or 0 to 7, from right to left), you’ll activate option 1 by selecting it with keys 8 and 9 and then adjusting the setting with the volume [-] and volume [+] keys. This will result in a value of 12 (12) next to “Option 6” on the screen. The options are binary, so 1 means it is activated, and 0 means it is deactivated.
Here’s the RGB deactivated, showing only the sync. I disabled Option 4 while testing—it’s activated by default and should remain activated (you won’t need to change it). Option 1 is the one we’re interested in here:
Confirm with the “Ok” key and “restart” the TV (turn it off and on again). Next, we have the RGB image already activated, but I entered the service menu anyway to set back the default value of option 4. In the end, it has to look like this, with value 12:
Running in the background, The King of Fighters 96, via Neo Geo emulator on the Raspberry Pi Zero, configured to have video output at 240p at 15kHz.
There are other options with different binary values that you can tweak if you want; some are related to the image format, but I do not recommend messing with them, as IT’s NOT REALLY necessary. The first time I tested it, I ended up activating a value that distorted the image on all four edges; the image was stretched, and that was precisely the image we’re seeing in the photo there. You can’t see it because the photo was taken from a very close distance, so the middle of the screen was normal. It was after activating that option, which distorted the image, that I realized why the guy using the Mux method had issues with Wonky Images; he certainly made the same mistake.
Preparing for the Tests
There are two simple ways to perform the tests:
1 — Testing the RGB MOD via Raspberry Pi
Using a Raspberry Pi is the easiest method I know since all you need to do is install RetroPie and then change 3 lines in the configuration file, which can be accessed via Windows or Linux and is located in the root directory of the RetroPie installation. This way, you will configure RetroPie to use a resolution of 240p at 15kHz. Keep in mind that if you are using Windows, you will need to use the freeware Notepad++, as the Windows Notepad App changes the character encoding of the file (thus corrupting the file). I won’t teach you how to install RetroPie because if you are doing this mod to use with the Raspberry Pi, it means you already know the basics of using the freeware Raspberry Pi Imager to record images on a flash drive, and it is a quite intuitive software.
Here’s a simple tutorial for the Raspberry Pi Zero, but the same type of thing could also be done with other versions of Raspberry Pi. The following code should be used in the RetroPie configuration file:
hdmi_group=2
hdmi_mode=87
hdmi_cvt=336 249 60 1 0 0 0The hdmi_cvt part is responsible for the resolution, which would be 336 pixels width by 249 pixels height, but this is the total resolution after taking into account values like Front Porch and Back Porch.
If your TV is PAL, then use the following code for the hdmi_cvt section:
hdmi_cvt=320 312 50 1 0 0 0249p provides a signal much closer to the original specification than 262p, where at 262p, the Raspberry Pi outputs a frequency of 16.2 kHz at 59 fps, with a slightly high horizontal frequency, causing the screen to narrow. With 249p, you’ll get 15.6 kHz at 59.6 fps, which is much closer to the specification.
Here are the video settings for use with the emulator:
For All Emulators
Aspect Ratio Index: Custom
Integer Scale: OFF
HW Bilinear Filtering: ONAll other settings should remain unchanged except for the following:
- Atari 2600:
Custom Viewport X Pos: 9
Custom Viewport Y Pos: 24
Custom Viewport Width: 320 (1x)
Custom Viewport Height: 210 (1x)- Atari 7800:
CVXP: 9
CVYP: 9
CVW: 320 (1x)
CVH: 240 (1x)- LYNX:
CVXP: 9
CVYP: 27
CVW: 320 (2x)
CVH: 204 (2x)- FBA (Capcom Play System):
CVXP: 9
CVYP: 18
CVW: 310
CVH: 224 (1x)- FDS/NES/SNES:
CVXP: 9
CVYP: 18
CVW: 320
CVH: 224 (1x)- GameGear:
CVXP: 9
CVYP: 14
CVW: 320
CVH: 231- GB/GBC/NP/NPC:
CVXP: 10
CVYP: 15
CVW: 318
CVH: 230- MAME:
Many games have different resolutions, making it difficult to specify one setting here. - Master System/SG-1000:
CVXP: 9
CVYP: 33
CVW: 320
CVH: 192 (1x)Mega Drive/32X:
CVXP: 9
CVYP: 17
CVW: 320 (1x)
CVH: 224 (1x)- N64:
Not available. The Nintendo 64 core already has a good image quality with the default settings. - Neo-Geo:
CVXP: 10
CVYP: 18
CVW: 320
CVH: 224 (1x)Keep in mind that some games run natively at 320 or 304 pixels width. Here, 320 is maintained for most games.
- PCE:
CVXP: 8
CVYP: 10
CVW: 320
CVH: 240 (1x)- PSX:
CVXP: 9
CVYP: 10
CVW: 320 (1x)
CVH: 240 (1x)Source: RetroPie 240p 15 KHz RGB SCART TV Guide
RetroPie running at 15kHz on a CRT TV demo:
2 — Via PC
Using a PC is a bit more complex, as unless you have a professional game converter, like a GBS 8200 v4, you’ll need to use a freeware, in this case, we’ll use the CRU (Custom Resolution Unity).
Here’s a tutorial on how to use Retroarch with a super resolution of 2560×480. In our case, we need to use 2560×240 or 1920×240, as 240p is the maximum supported by SD TVs (the CRTs we are using). Just follow the tutorial to the letter, but use 240p instead of 480p:
Connecting the PC to the TV
If your graphics card only has HDMI output, you’ll need an HDMI to VGA converter to connect to the TV, as we’re dealing with an analog RGB signal. Not just any converter will work. By way of example, I’ve already bought two white converters, and both burned out. Today, the converter I recommend is the one on the right (see the picture):
The black converter comes pre-configured with a few resolutions and is quite durable. The white converter not only lacks the convenience of a pre-configuration but also burns out in a matter of time if used for gaming. Recently, my black converter speaker jack broke, and when I opened it up to solder, I noticed it had more SMD components as compared to the white one, which I had also opened — and it barely had anything at all, just a jumper, a resistor, and a capacitor, as far as I remember.
Connecting the VGA is straightforward. Firstly, you’ll buy an HD15 VGA Female connector and then solder the wires exactly as shown in the picture below:
Remember that Hsync and Vsync need to be joined together to create a C-sync (composite synchronism), which will be connected to the diode and resistor in parallel and then go directly to the rear AV input.
This same procedure could be done with RCA component video inputs as well:
I only use VGA connectors for convenience.
Testing with Classic Games
The following images were only possible thanks to the CRU (Custom Resolution Unit) configuration, allowing various resolutions and frequencies between 60 and 63 Hz/15 to 16kHz, with the HDMI to VGA converter.
In-person, these images are much better, but I think my camera is to blame. Ever since my phone broke, all I have is a potato-cybershot that I picked from a garden. Some parts show motion blur, but that’s the camera’s fault because of its ISO— the TV doesn’t have any motion blur.
Retroarch tests with pixel-perfect images, displayed in a super resolution of 2060×240, progressive, without filters, as close as possible to each console’s original quality:
Pixel-perfect images:
- Mega Man X
- Metal Slug 2
- Biker Mice from Mars
- The King of Fighters 96
Video Playback
480p video being played at full screen resolution of 350×240, loaded directly from Google Drive:
- Love Hina
The following are photos from screenshots:
- Final Fantasy IX
Everything you saw here was reproduced through progressive scan; my video card (RTX 2060), at the time, did not support interlacing, so you’re seeing the best of the mod.
Testing with Modern Games
- Ride 4
- WRC9
Conclusion
That’s it; no need for the mux method here, no need for workarounds, just implement the RGB MOD normally on the board via OSD. This type of television is the easiest of all to make the RGB MOD since the Micronas chip doesn’t require the clunky 4PDT switch. The pro of this TV is that it has a single chip that handles everything, so the TV’s OSD menu doesn’t disappear or get messed up when the RGB Mod is activated.
To turn the external RGB on and off, a simple on/off button will do (as mentioned earlier), but it also needs to be deactivated via software, this is the con of this TV. This last part is the con of this model because you have to open the service menu every time you want to activate or deactivate the external RGB, however, this won’t be an inconvenience for those who will only use the TV with external RGB signals — meaning, for those who won’t be watching Mexican soap operas, neither use the TV as a monitor via composite or component video. To exit the service menu, just press the “normalize” button on the remote, but changes to the memory only take effect after the TV is turned off and back on. When the external RGB is activated, a PIP menu appears in the TV’s main menu; don’t be alarmed, this is irrelevant to us and doesn’t interfere in anything at all.
Trust me, this is one of the best CRTs I’ve ever seen. It only falls short in interlacing, which can be bothersome if you’re as picky as I am about image quality, but you get used to it and you’ll hardly notice it anymore. Most people, they’ll only get something of equal or better quality than this TV with a Sony or Toshiba A-series; I don’t know of any other consumer SD set that’s as good as this Panasonic.
So that’s it; this was the RGB Mod for the Panasonic TC29FX32L.
Points for Improvement
I don’t have this TV anymore, but these are the things I wrote for improvement back then:
1 — Resolder the Micronas wires “30 AWG.” I don’t even know where to buy this; my local hardware store doesn’t have it. I’ll probably have to order it online. I’ve also thought about using magnet wire, like the kind that’s used in headphones, but I still prefer the 30 AWG for its durability. This 30 AWG is the same type used in PlayStation 2 unlocking chips.
2 — I need to verify if I could remove some dark spots at the top of the screen. I hope it’s not a “burn-in effect.”
3 — The CRT is magnetized on the left side. I was disappointed to buy a PTC (thermistor) to replace the one in the TV, only to find that the it is counterfeit. There was no way to exchange it; it was imported. But this is easy to fix; a PTC from any 14, 21, or 29-inch TV will do. I just have to be lucky enough to find one.
Update: I was gifted with a PTC from a TV repair technician and swapped it out, but it didn’t resolve the issue. I have a 14” Toshiba here; maybe its PTC will work, and I put the one from the Panasonic on it.
4 — Post videos of the TV in the article.
5 — I believe the image can still be improved because when I set the default horizontal values in the service menu, the image got a bit squished. I had to stretch it to fit the screen. The horizontal IC might have problems or something in the horizontal region; it could be a blown capacitor.
Overall, this TV is excellent. If you’re considering buying one of these, just do it — don’t think twice. Trust me; you’ll love this TV. If it’s in perfect condition, you could pay up to 20% of its original value; the model itself is worth every penny. However, it has a more defined image than the Sony Wega, with less expressive scanlines, making it more similar to an arcade monitor, as seen below (zoom in):
Therefore, if you intend to use the TV solely for 2D games, especially those from the 16-bit era, I recommend getting a Sony Wega unless you don’t mind NOT having scanlines as wide as a pencil.
Questions, suggestions, gossip, cake recipes — post in the comments. I’m here to reply. Cheers!
