TV RGB mod thread

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MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

francoisadt wrote:
tongshadow wrote:Ok, anyone familiar with RGB mods on LG TVs?
I have a model that supports RGB through SCART and all I apparently need is to install the socket and add the missing components. However, there's no option in the service menu to enable a SCART/RGB channel. Would a voltage on the blanking pin (Pins 16 and 8 maybe?) be enough to display a RGB image? Here's a picture of the schematic:
https://i.imgur.com/y8bnQDF.png
Hi

I am busy planning to mod a LG CRT TV, getting a feed from arcade pcb analog rgb video.

I have bumped into this great resource about arcade analog rgb mapping to scart explaining which resistors sizes to use for each line!!! to lower the voltage to scart levels as Mark suggested here.
Great resource, I am just looking at jamma2euro scart section but lots of info here.
http://www.geocities.ws/podernixie/htpc/jamma2euro.gif
the site link:
http://www.geocities.ws/podernixie/htpc ... #vgaarcade

Other resources for those look here:
http://scarthunter.blogspot.com/2012/04 ... e.html?m=1

Another vga/rgb to scart using schematics, too difficult for me but for those that are experts this could be a great find:
http://members.optusnet.com.au/eviltim/ ... ga2arc.htm

regards
Francois du Toit

Since CRT Emudriver started outputting csync the need for the combination of H and V sync in the "VGA" to scart cables is no longer necessary. Just a resistor on csync.
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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
tongshadow
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Re: TV RGB mod thread

Post by tongshadow »

MarkOZLAD wrote:
tongshadow wrote:Would a voltage on the blanking pin (Pins 16 and 8 maybe?) be enough to display a RGB image? Here's a picture of the schematic:
There's one way to find out.
Didnt work out, unfortunately. It also messes up with the component input due to the extra grounded RGB resistors in line. Apparently this set was designed to use either RGB OR Component, not both.
The service menu SCART option is definitely a must for these LG sets if you want to RGB mod it properly.

And here I thought I could get the ultimate 29" SDTV CRT by having both RGB SCART and component input at the same time. :(
BevelTipDrip
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Re: TV RGB mod thread

Post by BevelTipDrip »

Hey guys, First time poster, long long loooong time lurker. I've done about 6 RGB mods at this point but for this most recent one I am gonna need a little input.

I just picked up a 27XBR36 and I've already got a mod mocked up and a good proof of concept hooked up, I'm using a custom PCB that uses a THS7374 to feed R/G/B into the jungle. (wow it looks amazing!) but there's one small problem. I'm not getting full blanking! when RGB is on it's clear there's a transparent composite signal underneath, I'm feeding 5v to YS and 0v to YM (YM is isolated entirely, unless the schematic isn't accurate!). So my question is, does anyone know if there's a good way to get full blanking? I'm thinking that I'll need to use a sync stripper on the input I'm using for sync, that should work alright yeah? For the record the jungle is a CXA1465as.

Link of 240p man to show you the issue
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Can you share the service manual.

If the RGB and component lines are shared you should only need one set of termination resistors.
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MarkOZLAD
OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
tongshadow
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Re: TV RGB mod thread

Post by tongshadow »

MarkOZLAD wrote:Can you share the service manual.

If the RGB and component lines are shared you should only need one set of termination resistors.
They have the same pins, but come from different AV lines, so they clash.
https://elektrotanya.com/lg_29cc2rl_29c ... nload.html
It's pointless anyways, since the blanking input voltage wasnt enough to enable RGB on AV1.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

tongshadow wrote:
MarkOZLAD wrote:Can you share the service manual.

If the RGB and component lines are shared you should only need one set of termination resistors.
They have the same pins, but come from different AV lines, so they clash.
https://elektrotanya.com/lg_29cc2rl_29c ... nload.html
It's pointless anyways, since the blanking input voltage wasnt enough to enable RGB on AV1.
Yeah if the scart option that shows in the service manual isn’t available on the set I think you’re out of luck. In my experience those TDA12XXX have to have the RGB option set in software for the input to be enabled.
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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
tongshadow
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Re: TV RGB mod thread

Post by tongshadow »

After doing some more research I realized my TV has a different chassis (CW-62C) from the models (CW-62A) that have the SCART option in the service menu.

So yea, there's still hope for those who have that chassis model. Lesson learned: Always look up the chassis number, and never the model because there can be variations.
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

Hello. I am modding an RCA E13309 13-inch TV (TX808A Chassis) for RGB and Composite. I was able to get Composite video to work by flashing the firmware from an E13318 and soldering a 4-pin header onto BE01 for my RCA jacks (Composite video and mono audio) to plug into. As for RGB modding it, I've been lurking on this thread for a while and came across some posts where a member here was attempting to mod an E13320, this particular post helped me determine my resistor values and switch wiring.

Using parts of the service manual and the post linked above as a reference, I've created a schematic that shows how I've attempted to RGB mod my TV (first image on the gallery linked below). After doing everything as described in my modding schematic, whenever I try to turn on this TV, the OSD appears hazy and it turns off after about 5-10 seconds. The breadboard is connected via DuPont connectors in order to make this easier to work with. I've also tried turning it on without my breadboard plugged in and it still gives the same result.

If anyone has any ideas on what I can try to fix these issues, I would appreciate it. (Right now, I'm thinking about either moving my RGB wires to the pads on the other side or replacing my 470 ohm resistors with 330 ohm ones in case the voltage is 0.5Vpp.)

NOTE: I forgot to take a photo of the breadboard, but my schematic gives you an idea of what it is.

Images: https://imgur.com/a/k5Ni7Up
Service Manual: https://docdro.id/bQJ9s6P
Roboplodicus
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Re: TV RGB mod thread

Post by Roboplodicus »

I want to recap then RGB mod my Sony 20v80 but I need help finding the service manual for it this is all I've found so far but it doesn't seem to be a full manual for the 20v80 and other sony screens that use the same chasis but it only has a list of the A board components for example. https://elektrotanya.com/sony_kv-13m40_ ... nload.html
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

That's about as complete of service manual as you can find for a TV.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Roboplodicus wrote:I want to recap then RGB mod my Sony 20v80 but I need help finding the service manual for it this is all I've found so far but it doesn't seem to be a full manual for the 20v80 and other sony screens that use the same chasis but it only has a list of the A board components for example. https://elektrotanya.com/sony_kv-13m40_ ... nload.html
As far as I can see it's all there. For the complete list of A board you need to use the list of common components plus the variant list appropriate to your set.
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MarkOZLAD
OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

KPackratt2k wrote:Hello. I am modding an RCA E13309 13-inch TV (TX808A Chassis) for RGB and Composite. I was able to get Composite video to work by flashing the firmware from an E13318 and soldering a 4-pin header onto BE01 for my RCA jacks (Composite video and mono audio) to plug into. As for RGB modding it, I've been lurking on this thread for a while and came across some posts where a member here was attempting to mod an E13320, this particular post helped me determine my resistor values and switch wiring.

Using parts of the service manual and the post linked above as a reference, I've created a schematic that shows how I've attempted to RGB mod my TV (first image on the gallery linked below). After doing everything as described in my modding schematic, whenever I try to turn on this TV, the OSD appears hazy and it turns off after about 5-10 seconds. The breadboard is connected via DuPont connectors in order to make this easier to work with. I've also tried turning it on without my breadboard plugged in and it still gives the same result.

If anyone has any ideas on what I can try to fix these issues, I would appreciate it. (Right now, I'm thinking about either moving my RGB wires to the pads on the other side or replacing my 470 ohm resistors with 330 ohm ones in case the voltage is 0.5Vpp.)

NOTE: I forgot to take a photo of the breadboard, but my schematic gives you an idea of what it is.

Images: https://imgur.com/a/k5Ni7Up
Service Manual: https://docdro.id/bQJ9s6P
R GND, B GND and G GND should be connected to ground. You schematic shows them connected to the same point as your external RGB. Is that how you wired it?
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MarkOZLAD
OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

MarkOZLAD wrote:R GND, B GND and G GND should be connected to ground. You schematic shows them connected to the same point as your external RGB. Is that how you wired it?
Originally I had my grounds connected to the common ground, specifically one of the grounding points of the BE01 pad for its (non-existent) RCA jacks. Just in case the RGB resistor grounding pads needed to be grounded, I've moved my grounds to the individual grounding pads on where the original OSD resistors used to be.

I've made some significant progress earlier today, I've determined that I needed to redo my breadboard with three sets of resistors instead of just two. I currently don't have pictures on hand, but here's the layout of the new (working) breadboard:

RR535 Positive - 680R (OSD R) - R CON + GND - 470R (MUX) + 75R (TERM.) - RR535 Ground
RR536 Positive - 680R (OSD G) - G CON + GND - 470R (MUX) + 75R (TERM.) - RR536 Ground
RR537 Positive - 680R (OSD B) - B CON + GND - 470R (MUX) + 75R (TERM.) - RR537 Ground

compared to the previous implementation, which didn't work as expected:

RR535 Positive - 470R (MUX) - R CON + GND - 75R (TERM.) - BE01 Ground
RR536 Positive - 470R (MUX) - G CON + GND - 75R (TERM.) - BE01 Ground
RR537 Positive - 470R (MUX) - B CON + GND - 75R (TERM.) - BE01 Ground

The reason why the TV was turning off with my old breadboard was that the lack of sufficient resistors was causing the CRT to increase in voltage. While I was testing with the old board, I kept turning the screen voltage down on the flyback until it was able to keep its power turned on, this resulted in the screen being too dark when I was testing with only 680R resistors going through the OSD lines. Since then I have adjusted the screen voltage back to a normal setting and it seems to be stable with my new breadboard.

So far, I have been able to get a good external RGB signal to display on it (using my PS1) and a functional OSD too. I will do some more work on it tomorrow (specifically designing the permanent breadboard and a jack panel to mount my RCA jacks on the back of the TV) and see how things turn out there.
Dildaria
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Re: TV RGB mod thread

Post by Dildaria »

I recently attempted to RGB OSD and Blanking mux mod an APEX GT2015 tv. I was able to get an image on the screen however any colors between 0-4 on the 240p test suite aren't showing up.
It appears they are too dark?

Original RGB and FB lines had
3300 ohm Inline resistors

RGB Lines had 680 ohm termination resistors.

FB line had a 3300 ohm termination resistor.

My current setup is
500 ohm ext RGB inline resistors
75 ohm ext RGB termination resistors

3300 ohm ext blanking inline resistor
180 ohm ext blanking resistor

LC86F344BA MiCon
LA76835 Signal Processor

Here are all the schematics I've found so far.

Apex GT2015 Schematics

I'm assuming I did something wrong :P
Any assistance would be greatly appreciated.

Here's what I plugged into the spreadsheet.
Image
Image
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Might need to upgrade the clamping caps to 1n.

Also after a quick read this set has Half-Tone blanking.

Try connect a pot to blanking , isolate the line or remove all termination (center pin blanking, outside pins 5v and ground)

Sweep the pot and see if you find a second level of blanking that fill the screen.

Image
Dildaria
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Re: TV RGB mod thread

Post by Dildaria »

Should I try the pot first or adding the 1nf caps first or both at the same time.
Dildaria
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Re: TV RGB mod thread

Post by Dildaria »

Rereading the service manual I've also noticed there appear to be settings for Halftone in the service menu should those be left alone?
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Try it all till something works.

You can find 1n caps on pretty much anything electronic so it should be a quick test.
Dildaria
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Re: TV RGB mod thread

Post by Dildaria »

So there is an option in the menu for Sub. BIAS. I adjusted this from 63 to 110 and this appears to have fixed the lack of colors on the 240p test suite between 0 to 4. Is this technically accomplishing what changing resistor or capacitor values would by increasing the voltage output to the tube? Should this suffice or should I attempt to swap out the capacitors at the signal processing IC and see if I can tune that back down to what I'm assuming is stock? Another note is that despite the GT-2015 service manual saying that a halftone option is present in the service menu it is not present for my model gt-2015.
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

I'm happy to report that the RCA E13309 (TX808A chassis) RGB mod was successful. While the previously mentioned breadboard design worked on a temporary breadboard, it was causing issues when I reproduced it on a permanent board, so I had to add jumper wires across the lines in order to keep the RGB lines active without anything plugged into external RGB. I've placed electrical tape over the permanent resistor board to prevent anything from shorting out and to keep the wires in place.

https://imgur.com/a/9fqVPTN

The image gallery contains a mod schematic for anyone who wants to perform this mod on another TV with a similar chassis, this mod was designed with BNC/RCA jacks in mind, so if you wish to use SCART, some additional modifications may be necessary. While the 3D-printed jack panel may seem a little awkward, I've designed it that way to make it easier to work on the TV, should I need to fix anything on it.

Here's a link to the RCA E13318 firmware for anyone who wishes to mod an RF-only model (like my E13309):
https://shema.info/en/firmware/26137-pr ... -9635.html

There are a couple issues with my TV, the speaker wire is faulty and the screen gets excessively bright at times (maybe a faulty flyback transformer?), both of which happened before I modded it, I can try to fix these issues at a later date.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Dildaria wrote:So there is an option in the menu for Sub. BIAS. I adjusted this from 63 to 110 and this appears to have fixed the lack of colors on the 240p test suite between 0 to 4. Is this technically accomplishing what changing resistor or capacitor values would by increasing the voltage output to the tube? Should this suffice or should I attempt to swap out the capacitors at the signal processing IC and see if I can tune that back down to what I'm assuming is stock? Another note is that despite the GT-2015 service manual saying that a halftone option is present in the service menu it is not present for my model gt-2015.
Did you adjust the screen (G2) pot?
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
Dildaria
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Re: TV RGB mod thread

Post by Dildaria »

No I did not adjust any pots.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Dildaria wrote:No I did not adjust any pots.
You might’ve been able to fix it just by adjusting screen voltage.
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MarkOZLAD
OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
Perafkraften
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Re: TV RGB mod thread

Post by Perafkraften »

Hi. Bought a TV exactly like the one I had as a kid. A telefunken mp 143. Now I want to connect either rgb or just composite to it because it only has rf out. Have taken out the motherboard after discharging the tube and taken every precaution. Found the microcontroller schematic and the jungle chip schematic. Can someone help me in the right direction. I have read up on the subject but don't want to destroy anything unnecessary.

https://drive.google.com/folderview?id= ... aFWdliRrHB
abispac
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Re: TV RGB mod thread

Post by abispac »

Image
So today ima pick up this 2 bad boys for 10 dlls each, i didnt want the lg, but the lady wants 5 bucks for that one, so ill think it over and maybe ill pick up that one too...im obsesed with rgb moding crts, although im still learning and screww up most of my attempts, so far out of 5 i had one succesfull attemp and that was because it was the exact same model as the 8bit guys so i just followed instruction straight. Anyway, ive seen people modding the white trinitron but some folks claim aint worth, so maybe ill leave that one alone and do the composite mod isntead. On the black one im hopping its a 13 inch set, as the lg is a 21 model, on the picture it looks a bit smaller. Anyway ill keep updating this. Pardon my english , is my second lenguage.
Roboplodicus
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Re: TV RGB mod thread

Post by Roboplodicus »

So I found this guide for the SSM 20N5U and I'm wondering if it could be used or atleast used for some good information for modding a 20N1U. viewtopic.php?f=6&t=66067 Here is the service manual for the 20N1U http://www.mediafire.com/file/ytohm708f ... U.pdf/file
obitus1990
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Re: TV RGB mod thread

Post by obitus1990 »

If a television doesn't have Composite video in (coax input for RF in on the tuner), can it be modded for RGB? I have a circa 1991 Orion TV1319 (RF input only) that uses a Sanyo LA76070 as its jungle IC, and the micro is an Orion OEC3027C. I've had it since new, and have, in the past had a VCR connected to it via the coax input.

Thanks!
DentedRazor
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Re: TV RGB mod thread

Post by DentedRazor »

Hey everyone. I recently got a Panasonic CT2786-VYD Color Video Monitor from a local university's auction for a few bucks, and would like to RGB mod it. Checking through all the pages of this thread, I noticed that its jungle chip (AN5165K) has been used in other user's TVs, but I haven't seen a similar circuit to this one in terms of the terminating resistors at the R-G-B IN. The terminating resistor's are much larger in size compared to the inline resistors, having a larger voltage going into the RGB IN pins (over 4V) unlike the others I have seen (0.5 or 0.7). Below is the circuit from the service manual with red lines for my current findings.

Image

Despite this, would the MUX RGB mod still work with this particular CRT, since those terminating resistors are removed anyway?

The documentation seems to indicate the lower voltage would still be fine, since the recommended use range of those pins are 0-6V ( the AN5165K's documentation ).

Thanks!
Dildaria
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Re: TV RGB mod thread

Post by Dildaria »

https://www.youtube.com/watch?v=RhhxpW_Bxtk

Looks like it is possible to mod that Orion
BevelTipDrip
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Re: TV RGB mod thread

Post by BevelTipDrip »

BevelTipDrip wrote:Hey guys, First time poster, long long loooong time lurker. I've done about 6 RGB mods at this point but for this most recent one I am gonna need a little input.

I just picked up a 27XBR36 and I've already got a mod mocked up and a good proof of concept hooked up, I'm using a custom PCB that uses a THS7374 to feed R/G/B into the jungle. (wow it looks amazing!) but there's one small problem. I'm not getting full blanking! when RGB is on it's clear there's a transparent composite signal underneath, I'm feeding 5v to YS and 0v to YM (YM is isolated entirely, unless the schematic isn't accurate!). So my question is, does anyone know if there's a good way to get full blanking? I'm thinking that I'll need to use a sync stripper on the input I'm using for sync, that should work alright yeah? For the record the jungle is a CXA1465as.

Link of 240p man to show you the issue
Anybody have any input? I've decided to add a fourth BNC with a sync stripper that goes into one of the composite lines. I'll let people know how it works, I'm going to write up this mod when I am done because it's fairly simple, but also a pain in the ass haha.
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