TV RGB mod thread

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Pikkon
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Re: TV RGB mod thread

Post by Pikkon »

poipo32 wrote:
Osirus wrote:Look into pins 16, 17, and 18.
From what I gather from reading old threads on TV repair forums, pins 16, 17, and 18 of the CXA1477AS are analog RGB, used for the closed captioning.
While pins 19, 20, and 21 are digital RGB used for the OSD.

It seems Ys (pin 10) would be my fast blanking, which is the pin I was most unsure about.

Since I don't care about closed captioning, I'm going to try a mod with no signal mux.
I'll just disconnect the incoming RGB signal.
If I lose the OSD, I'll go back and do a signal mux.

I'll post the results in this thread.

Spud posted a block diagram for the CXA1477AS.
viewtopic.php?p=1408786#p1408786

Pin 10 is blanking.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

nes.og wrote:Can anyone please tell me when diodes are required and when they are not?

Thanks
Some people use them to prevent your RGB blanking voltage from applying an input voltage to the blanking output of the microcontroller. Personally I've never used one.
nes.og
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Re: TV RGB mod thread

Post by nes.og »

Thanks for the info!
Osirus wrote:
nes.og wrote:Can anyone please tell me when diodes are required and when they are not?

Thanks
Some people use them to prevent your RGB blanking voltage from applying an input voltage to the blanking output of the microcontroller. Personally I've never used one.
snappleman
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Re: TV RGB mod thread

Post by snappleman »

So I'm trying to mod this RCA 24V510T and I noticed the jungle IC labels the RGB2 inputs as YIN UIN and VIN. One of the codes in the service menu enabled a YPbPr/DVD input, so I assume it's software locked to component and wont accept RGB, but I actually would prefer component. I just need some help figuring out how to properly wire component jacks to the board. Here's the schematic:
Spoiler
Image
When switching to the YPbPr input the screen had this strange purple pattern flickering around as if it was out of sync. I checked the PCB and saw that the capacitors at C159, C129 and C158 were unpopulated, so I added those in. But the schematic doesn't show that there are resistors in line with the U and V lines (also unpopulated).

I am wondering what those values should be, and also where to solder in my jacks for the input, here's there PCB:
Spoiler
Image
I've colored in the traces to see where they go, the U and V go to the unpopulated spots where the component inputs would be, but the Y is confusing me a bit (and I assume the farthest most unpopulated spots are for the audio going to the YPbPr input).

So my questions are what resistor values should I use at R817 and R815 (the schematic has no parts list...) and where should I connect the Y input?
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

snappleman wrote:So my questions are what resistor values should I use at R817 and R815 (the schematic has no parts list...) and where should I connect the Y input?
You can likely just jumper those. I have seen values around 100 ohm being used in those spots.

Y is Green.
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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
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

nes.og wrote:Can anyone please tell me when diodes are required and when they are not?

Thanks
It's a very good question. I can't tell you a way to predict when you will need them but I have had sets that simply do not work without the diodes. LG MC009A chassis with a SDA5555 micro controller was one example. Not sure why, the micro controller was possibly holding the rgb lines low or something.

If you wanted to you could just always use diodes. Would work in the cases where they are and aren't required.
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OSD/External RGB Mux Diagram
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maxtherabbit
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Re: TV RGB mod thread

Post by maxtherabbit »

I always use the diodes. Good insurance and they don't cost anything
snappleman
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Re: TV RGB mod thread

Post by snappleman »

MarkOZLAD wrote:
snappleman wrote:So my questions are what resistor values should I use at R817 and R815 (the schematic has no parts list...) and where should I connect the Y input?
You can likely just jumper those. I have seen values around 100 ohm being used in those spots.

Y is Green.

Thanks! What I ended up doing was finding the schematics for another TV in the same product line that used the same board but had the component video populated, gave me all the values (you were right about 100ohm) and also showed the full path of the Y circuit which had me populating the board with even more caps, resistors and two transistors. Long story short I got it working perfectly.
Eddyiori
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Re: TV RGB mod thread

Post by Eddyiori »

Hello guys here I am again with a new tv trying to make this mod a reality.
I have connected rgb and fastblanking but I get nothing. To what I have made before when 5v is inserted to fasblanking pin it should clear the image right? maybe I'm missing something.
here is the service manual
https://mega.nz/file/Mr5QiZwY#pWdWdl1BE ... yWGnBVI3v0

Image

Here is the datasheet for the jungle ic
http://www.datasheet.es/PDF/870554/TDA9583H-pdf.html
Mystic_Merlin
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Re: TV RGB mod thread

Post by Mystic_Merlin »

Hello guys, first of all a big thanks to all the contributors on this thread. I was able to mod a Sony Tv with a BG-3S via Teletext injection and I've been enjoying it ever since.

Now I'm trying to mod another quite similar model for a friend, this one has a BG2T chassis.
It also has an unpopulated Teletext connector CN001 and conveniently 0.1uf caps in line with RGB.

I took out the R330, R331, R332 and used 75 ohm resistors to GND on the scart connector

My current issue is that it displays a black screen when I switch the blanking signal, though it works via composite. I feel like I'm missing something or my RGB levels are too low.

There are slight differences with the schematics on my board though, first R330, R331 and R332 were not 470 ohm but 0 ohm. Also R329 is 560 ohm instead of 470. I guess these were set by default as Teletext was not installed.

Image
Image
Image
Image

I could go traditional OSD method but Teletext is so much more practical and elegant.
Any help would be greatly appreciated :D
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OGLZ
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Re: TV RGB mod thread

Post by OGLZ »

Hello, people of the Shmups Forum, I apologize if I am posting incorrectly. I am new, but have been lurking on threads here for a month or so. I am interested in RBG modding my TV, but I have several questions on how to do so.
First off here is some information about my TV.
Brand: Emerson/Funai
Model: cr202em9
Manufacturer Date: Oct 2007
TV Microcontroller: IC111
(Not sure what else to include)
So I have seen 1 Reddit post about RGB modding this TV, and it talked about a DIY amp to the neck board. I am very confused on what this means, here is the Reddit link -> https://www.reddit.com/r/crtgaming/comm ... _diagrams/. Secondly, I am confused on where I should even attach my cables. Going off the IC111 the RGB lines all hit a 2.2k resistor, then a diode, then I think a 100 resistor after that. The resistors are all surface mount, so can I just attach my leads to the through-hole diodes? I have been researching pretty extensively for 2 weeks or so, and have disassembled the TV. I am just being very cautious and would like someone's advice, as this is my main retro gaming TV.
I've also attached an image of the Video Block Diagram
https://i.imgur.com/rz4TFur.png

Thank you so much!!
Back pain for beautiful frames
zFleeman
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Re: TV RGB mod thread

Post by zFleeman »

For whatever reason, I'm getting the itch to RGB mod another CRT, and somebody is willing to drop off an Orion TV1934a to me this evening to work on. I'm looking at what I believe is this TV's service manual, but it looks like there are a few different schematics inside of this one pdf:

service manual

If I'm reading this correctly, it looks to be a simple-enough mod. I just want to check my work because I haven't done this in nearly a year.
  • 4.7k (R123, R122, R121) resistors on the RGB lines will have me using 750ohm resistors on the external lines
  • I need to remove R102, R103, and R104 and instead ground my external line with 75ohm
  • I don't know where to pull 5v for blanking to go into the jungle chip... I actually need some help here.
Does that sound right?

But again, it looks like this one service manual has a couple of schematics with different ICs, so I'm not sure.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

zFleeman wrote:For whatever reason, I'm getting the itch to RGB mod another CRT, and somebody is willing to drop off an Orion TV1934a to me this evening to work on. I'm looking at what I believe is this TV's service manual, but it looks like there are a few different schematics inside of this one pdf:

service manual

If I'm reading this correctly, it looks to be a simple-enough mod. I just want to check my work because I haven't done this in nearly a year.
  • 4.7k (R123, R122, R121) resistors on the RGB lines will have me using 750ohm resistors on the external lines
  • I need to remove R102, R103, and R104 and instead ground my external line with 75ohm
  • I don't know where to pull 5v for blanking to go into the jungle chip... I actually need some help here.
Does that sound right?

But again, it looks like this one service manual has a couple of schematics with different ICs, so I'm not sure.
Pull 5v from pin 22 on the microcontroller.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Eddyiori wrote:Hello guys here I am again with a new tv trying to make this mod a reality.
I have connected rgb and fastblanking but I get nothing. To what I have made before when 5v is inserted to fasblanking pin it should clear the image right? maybe I'm missing something.
here is the service manual
https://mega.nz/file/Mr5QiZwY#pWdWdl1BE ... yWGnBVI3v0

Image

Here is the datasheet for the jungle ic
http://www.datasheet.es/PDF/870554/TDA9583H-pdf.html
It is highly likely that your set's jungle chip is locked to only receive component. Search the service menu options, there may be a way to change it.
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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
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

zFleeman wrote: [*]I need to remove R102, R103, and R104 and instead ground my external line with 75ohm
OSD Mux targetting R102,R103 and R104. Inline Mux resistor of value 750 ohm (as well as the 75 ohm termination)
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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
Jacib
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Re: TV RGB mod thread

Post by Jacib »

Hello, I have a Sony Tinitron KV-32S22. i am trying to rgb mod this and am using db25 pin, so i am just worried about r,g,b and c-sync. i have spliced the rgb wire going to the tube into a switch,and have tried a few synch pins on the back and also on the ic/jungle.

was wondering if i am going to have to take all the boards out/off of case completely, and if i would have to end up pulling a pin(s) from the jungle chip for synch or rgb (i can fix my splice). also if will have to pull a pin up out of the board and isolate it (i.e remake the switch).

Any information regarding this TV would be greatly appreciated!


https://www.manualslib.com/manual/89095 ... 32s22.html
benyamin39
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Re: TV RGB mod thread

Post by benyamin39 »

Syntax wrote:Your 5v blanking line was back feeding into the micron and activating it?

Diode should sort that.

Dropping the screen voltage to get ideal brightness doesn't seem right.
Does 240p test suit color bars look ok or black crush?
Double check your termination total or test .5vpp video if so.
I have found a 19 in Samsung CRT TV. Model is txh1973. Chassis is K15A, Chroma is TA1282N and OSD Zilog 3757, wiring diagram is exactly the same as the TV megasdkirby has modded, the only difference is the OSD chip which is different. Otherwise the line resistor is 7.5kohm. ground resistors is 1.2kohm. RU10 680ohm is there as well.

I previously modded another 19 in Samsung CRT TV using the OSD Mux method developed by MarkOZLAD for the 8bit guy. It worked straight from the bat.

This one has obviously the same symptoms as megasdkirby indicated in his mod. Screen is too bright. Where does it come from and is there an alternative to modifying the flybackwheel?

I tried to snip the OSD entirely and inject RGB signal straight to the chroma, with various inline resistors value and ground resistor values to see if I could get anything.

Any ground resistor value of 75 ohm or below : The image is too dim (btw if I jump RU10 I got the same dim screen and the OSD becomes invisible. this is one difference I got with megasdkirby. I can't explain why, but this is consistent with my findings when I snip the OSD. maybe it is because the OSD chip is different. Another finding is even if I snip RGB line from OSD I can still have access to the menu! I guess the signal is coming from the CCD line through the common ground line? no problem here though)

Any ground resistor of 240 ohm or above (or even no ground resistor at all), the image is too bright and some details in the picture get lost.

Anything in between is not satisfactory either (I tried 83,100,120 ohm) . So basically I can’t find a voltage divider arrangement that seems to work. Theoretically a 75ohm ground resistor should give me 0.7Vpp.

To rule out any other option, I tested various values for the inline resistor (including 1200ohm), this does not change anything, which is expected as I entirely sniped the OSD, so there is no more voltage divider there.

Picture from my first samsung TV. Crisp, beautiful, I want to repeat that one.
Image

Picture from this txh1973 model, meh ...
Image

Thx for anyone insight, to help me understand. And if flybackwheel is the only solution, then at least I will understand why.

Here-below is the traced PCB
Image
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Mystic_Merlin wrote: My current issue is that it displays a black screen when I switch the blanking signal, though it works via composite. I feel like I'm missing something or my RGB levels are too low.
You need to read the TDA884X Datasheet and check on the voltage levels for blanking.

"A traditional OSD method" will not be of any use, this is a post mixed OSD. Text port the only real solution here.
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OSD/External RGB Mux Diagram
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

Jacib wrote:Hello, I have a Sony Tinitron KV-32S22. i am trying to rgb mod this and am using db25 pin, so i am just worried about r,g,b and c-sync. i have spliced the rgb wire going to the tube into a switch,and have tried a few synch pins on the back and also on the ic/jungle.

was wondering if i am going to have to take all the boards out/off of case completely, and if i would have to end up pulling a pin(s) from the jungle chip for synch or rgb (i can fix my splice). also if will have to pull a pin up out of the board and isolate it (i.e remake the switch).

Any information regarding this TV would be greatly appreciated!


https://www.manualslib.com/manual/89095 ... 32s22.html
AA-2D is a well documented mod done by quite a few people already. Mostly typical OSD mix except for the fact that the micro outputs digital RGB which gets converted to analog before going to the Jungle. Just have to do your injection after the A/D conversion circuit.

viewtopic.php?p=1429634#p1429634
Mystic_Merlin
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Re: TV RGB mod thread

Post by Mystic_Merlin »

MarkOZLAD wrote: You need to read the TDA884X Datasheet and check on the voltage levels for blanking.

"A traditional OSD method" will not be of any use, this is a post mixed OSD. Text port the only real solution here.
Thank you very much Mark! I'm not sure why my first post took several days to get published but in the meantime I did exactly what you suggested and noticed the blanking voltage needed to be lowered down. I made a voltage divider with 2x75 ohm resistors (not sure if more is needed) on the +5V bringing it down to 2.3V and now it works perfectly.
Thanks again for your numerous contributions to this thread, it seems we have a few common TV chassis between Thailand and Australia :wink:
snappleman
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Re: TV RGB mod thread

Post by snappleman »

I found this JVC C-20210 in the trash and am trying to mod it. It's got a TA1242N in it and doing a search here bought up a post someone made for modding that and said it worked well. I did the mostly mod the same way, just soldering RGB and blanking directly to the chip, though I found some nearby jumpers to solder to, except I am using the composite video input for the sync for now. And it has me tapping 5V from the tuner and wiring that to a switch.

The problem is it doesn't work properly. The picture starts very dark and slowly brightens up, but it doesn't stop when it looks correct, it keeps getting brighter and more washed out, so I immediately turned it off. I was using my Genesis and I read that they do something funky with the sync, but I don't want to try with another console until I get some advice.

I read the datasheet for the TA1242N and it says (in Japanese) something about the blanking pin threshold being 1.5v so am I harming it by using 5v? Or does that mean at least 1.5v for it to work? Also should I be doing other things like the 75ohm resistors, blanking from SCART, resistor+cap in series with sync, not using composite input for sync etc? The post I read about this said that these aren't needed and I guess I got too excited and rushed it...

Service manual is here:

https://elektrotanya.com/jvc_av-20221s_ ... nload.html
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

You definitely need 75 ohm terminations for your RGB inputs at the very least. You probably also need caps for the RGB going into the jungle chip.
snappleman
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Re: TV RGB mod thread

Post by snappleman »

I assumed as much, I just saw that old post and got excited to take shortcuts and not go digging through my stuff for the components at 2am and risk waking my 9 month old (and then I proceeded to record a guitar amp for a work session...)

Anyway I found the thread MarkOZLAD made with the OSD mux calculator and all that, I'll take my time and actually learn what I'm doing before I blow stuff up. With all the ridiculous amounts of information on here I feel a bit embarrassed asking such ignorant questions :D
xer0510
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Re: TV RGB mod thread

Post by xer0510 »

So i just came up on a kv-32s40 and my game plan is to lift the pins, run the RGB from the jungle ic to scart and use composite from video 1 for sync, then tie YS pin to 5v and finally make sure everything is grounded properly.

So my question are

i dont have any .1uF caps on hand, could i use .2uF instead? i do have some .1uF polarized caps could i use those?

Is running 3 resistors in series that equals 75ohm ok?

last will using 5v stand-by be ok for blanking?
snappleman
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Re: TV RGB mod thread

Post by snappleman »

I'd wait for the experts to answer but I only had 0.01uf caps and those seem to work fine for me.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

xer0510 wrote:So i just came up on a kv-32s40 and my game plan is to lift the pins, run the RGB from the jungle ic to scart and use composite from video 1 for sync, then tie YS pin to 5v and finally make sure everything is grounded properly.

So my question are

i dont have any .1uF caps on hand, could i use .2uF instead? i do have some .1uF polarized caps could i use those?

Is running 3 resistors in series that equals 75ohm ok?

last will using 5v stand-by be ok for blanking?
That model has been done, it’s an AA-2D. OSD Mux. If you search this thread for AA-2D you should find it.
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OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

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Osirus
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Re: TV RGB mod thread

Post by Osirus »

MarkOZLAD wrote:
That model has been done, it’s an AA-2D. OSD Mux. If you search this thread for AA-2D you should find it.
Just 5 replies back in fact.
xer0510
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Re: TV RGB mod thread

Post by xer0510 »

right on , guess this will do.

Osirus wrote: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.
Is this more or less the idea?
https://drive.google.com/file/d/1N92jBk ... sp=sharing
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

I think so. I'm not entirely sure those CNs I used are present on every board, but they make the mod easy if they are and you have Dupont pins/connectors around.
xer0510
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Re: TV RGB mod thread

Post by xer0510 »

im a bit confused now, i might just be psyching myself out by overthinking it.

so step 1: Remove the three resistors.
step 2: run RGB BL from micron to CN 1801 and RGB BL from Jungle to 1802
step 3: Run the RGB from the scart head to CN 1801 with 75ohm to ground and 330 in series.
step 4: removed JR1801
step 5: run 5v with a 470 ohm resistor to middle terminal of the switch and Ys from the micron to the switch
step 6: run the YS from CN 1802 from jungle ic CN 1802 to the switch
step: 7: connect pin 20 of the scart to Y on s-video.
step 8: tap into YC/SW1, pin 6 of IC 1261 and run it to the switch.

im not to sure on how to wire up the dpdt switch.
Last edited by xer0510 on Mon Jul 05, 2021 5:52 am, edited 1 time in total.
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