TV RGB mod thread

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Hoagtech
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Re: TV RGB mod thread

Post by Hoagtech »

I had a chance to locate a form of RGB on the schematics.

Its on the OUTPUT LOGIC.


Image

Is that where I would inject RGBs?

It displays an OSD as it shows "VIDEO 1" in the corner, but I didn't see the jungle IC on the schematics other people were referring to.

If anyone can help. I would love to get this beautiful Trinitron working.
Copyright 1987
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Hoagtech wrote:I had a chance to locate a form of RGB on the schematics.

Its on the OUTPUT LOGIC.


Image

Is that where I would inject RGBs?

It displays an OSD as it shows "VIDEO 1" in the corner, but I didn't see the jungle IC on the schematics other people were referring to.

If anyone can help. I would love to get this beautiful Trinitron working.
Try this service manual instead.

https://elektrotanya.com/sony_kv-27ts29 ... nload.html
___________________________________________________
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
skum
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Location: Denmark

Re: TV RGB mod thread

Post by skum »

metralla19 wrote:Hi Guys!

I recently purchased a pvm monitor whose model is: JVC TM-A101G.
This monitor does not have output rgb, but my question is if it is possible to make a modification to the board to get RGB, and in that case, what kind of modification should be made.

Image

Image

I leave a link with the schematic of the board whose chip appears to have an analog RGB output.

Schematic: https://drive.google.com/open?id=198V3M ... FAw38x4pOm

Thank you very much!
Before you dive into the I2C stuff, I seem to have seen this exact monitor being easily RGB modded, by simply removing the caps to GND from the RGB pins (23,24,25), insert 5V on pin 22 (ensuring the resistor to GND is 1k or larger to avoid current draw), and then add sync to the input pin of one of the BNC composite inputs. If that works, you can then use the I2C stuff if you want brightness and contrast control to work. The I2C stuff mentioned on the page Mark links to, was because the A140PN messed with the RGB registers, so it was unusable.
Yulius
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Re: TV RGB mod thread

Post by Yulius »

MarkOZLAD wrote:
Yulius wrote:hi, im new in this forum and im learning how to do Tv crt RGB mod by osd mux.
actually i mod 2 sony BA-4D chassis and 1 and AA-2D (and work nice).

now i try to do osd mux on daewo tv, i used same metod but result in too dark image (all colors are obscured and osd letters are black now).
i need help with this tv please, i adjunt the schquematics i use on this tv.
(sorry for my english).

https://ibb.co/MV8CWNs
https://ibb.co/H2kQcfs
https://ibb.co/Wxzk604
https://ibb.co/ykmygYj
https://ibb.co/Xy96VVG
https://ibb.co/QDg41Xw
I believe your blanking circuit is incorrect.

the datasheet is here..

https://pdf1.alldatasheet.com/datasheet ... 251CN.html


Looks like your set might want 3.3V or more to blank as there is a half tone circuit on your set.

Image

These days on blanking circuits I like to cheat rather than bothering to make scart pin 16 do the blanking. After returning the set to factory blanking, I would just run a 5V line through a switch and then a 620 Ohm resistor onto the leg of RC730 (I think that's what is showing on schematic) that is farthest from the micro controller.

Like this

Image

This way we are just mimicking the way the TV's OSD blanks and you take away any need to do calculations.

Thanks!! I look the blanking circuit and add 5v by 620 ohm resistor (470+150 ohm resistors conected in series ) but for some reason when osd mux work and show osd menu with normal colors at 20 minutes the signal show interference and image switch in black and white colors, and osd menu show like a transparent.

I look again the circuit and try simulate in proteus software, finally i use 5v by 430 ohm resistor and RGB colors look nice, but when i press menu, the image show full black screen.

I dont like this, but for now the mod is stable, i play for 3 hours and dont have the the interference in the colors.

In this image i conected my ps2 by "rgb cable" ( i add composite sync in normal component cable for ps2 and in options y change ypbpr to RGB) my camera dont show true colors but look nice .


https://ibb.co/nQ0MJbB

https://ibb.co/Fx5z5zx

In the circuit i look a 10k ohm resistor to ground before jungle blanking input .
in simulator this resistor change the voltage.
But i dont know if this afect the voltage divider.

https://ibb.co/ZSq92mP

Pd: again sorry for my basic english
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

If you are going to use this TV as a dedicated RGB monitor you can remove the factory OSD blanking resistor RC730 from the chassis. This will leave the TV hard wired in RGB mode and when the OSD blanking occurs it won't affect the blanking voltage. The OSD should work nicely too.
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OSD/External RGB Mux Diagram
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
Yulius
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Re: TV RGB mod thread

Post by Yulius »

MarkOZLAD wrote:If you are going to use this TV as a dedicated RGB monitor you can remove the factory OSD blanking resistor RC730 from the chassis. This will leave the TV hard wired in RGB mode and when the OSD blanking occurs it won't affect the blanking voltage. The OSD should work nicely too.
Thanks so much for you`re help, i remove RC730 resistor and its works fine, for now i only conect my ps2 and ps1 by RGB and looks aweosome, i play with snes emulator for ps2 and y loved the colors. In weekend i need construct the cable vga to RGBS like 8bitguy shows in the seccond video, for connect my pc with calamity drivers and groovymame, My father will love this homemade arcade for his birthday


I don't want to abuse your help but today i finded a Panasonic Panablack tv when i going to work (lucky day). TV is operative but i dont find the number model.
https://ibb.co/SRNTGbD
(i like so much how look this tv)

i opened and clean the chassis have 2 chips, MN1874085T JW and AN5165K, searching in internet i find a service manual of the similar panasonic tv.

i studyed the circuit but i'm not sure how abord this RGB MUX because i dont see lines with resistors to ground in the rgb OSD output and dont see capacitors on RGB input in jungle chip (in other televisions ever have 0.01uf).

service manual:

https://mega.nz/#!tipRjQAT!SGYEq4v5D3KP ... Jgq29xG6wY

(only difference i see its in my tv i have 3 resistors to ground on the RGB jungle input, tester shows 19K ohm, but the code 333 smd is not these value and im not sure about the function of this resistors, posibly this are the resistor i need replace but im not sure)

this resistors:
https://ibb.co/HqxmYcr

datasheet AN5165K:
http://www.alldatasheet.com/view.jsp?Se ... YiEALw_wcB

i think for blanking i need 3.1v aprox
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

I suggest you reverse engineer the entire RGB circuit of your set.

It seems the AN5165K is being used in a digital mode on the schematic you sent. The datasheet is a little confusing but I think it can be used for analog RGB input. I would try and rewire it so that it works like other sets, by adding in OSD mux and 75R ground resistors and seeing what happens. Just need to find a place to attach to.
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Tengugurl
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Re: TV RGB mod thread

Post by Tengugurl »

Hi everyone!

New CRT modder here. Looking to learn lots and hopefully help future RGB modders.

Quick question:
Running into a snag with my RGB mod (Obsolete method as I started it before joining the forums and I want to see if I can accomplish it before I try Mux)

Issue experienced:
Sync is all over the place and the color is black and whiteish. (This my be fixed by fixing the sync)

Assumption:
1) Resistors/caps not added SCART socket yet.
Notes: I will add resistors and caps but they are in-transit from China so it will be a while

2) PDT switch
Notes: I am using an on/off/on switch and I am wondering if I need an on/on PDT switch?

Here is a video of what I am experiencing in my Obsolete RGB Mod (Aka switch between OSD, Common and SCART - I did this as a POC before I did the Mux method sorry in advance!)
https://youtu.be/uwcunL8VOU0

I want to get the Obsolete method working first as I am still learning all about CRTs and doing this mod.

Info:
Model: Sony Trinitron Kv-13vm42
Schematic: https://elektrotanya.com/sony_kv-13vm40 ... nload.html
Parts Used:
SCART FEMALE PORT: https://rover.ebay.com/rover/0/0/0?mpre ... 4362508286
Dupont Connectors: https://s.click.aliexpress.com/e/cH466h7w
PDT switch: https://rover.ebay.com/rover/0/0/0?mpre ... 1409045554

Thanks so much in advance <3
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Romariu
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Re: TV RGB mod thread

Post by Romariu »

I would like to modify my LG MC-83A TV but I do not know where to start.
Please help me.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

You say that the MVS is consolized.....Do you have any idea what the sync circuit is? If the MVS is outputting TTL level csync you should only need a 1K resistor on the sync and then send it into the existing AV port.
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Yeah that's some hot sync right there, and no caps or attenuation on the RGB lines.

You will need to consolise the video output like Mark said before proceeding.
SEGA-CD
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Re: TV RGB mod thread

Post by SEGA-CD »

Hi everyone, I am interesting in performing an RGB modification to an RCA 20F420T. It only supports composite and s-video which was fine years ago but it kinda sucks now. I have had trouble finding much relevant information on this television and most places just direct me to this forum. Last October I found some stuff for the same chassis (M123SP) but none of the schematics are for the 20F420T model in particular so I'm kinda lost as to what I should be looking for.

This is all the info I have on the TV: https://mega.nz/#!RqgERQpI!uWeNKNbpLz4P ... Rt-eyS2i4A

Assuming the above stuff is of any use, can someone who is more knowledgeable tell me if this TV can be modded and if so, pointers on how to do it? Thanks.
Last edited by SEGA-CD on Tue Jul 09, 2019 8:03 pm, edited 1 time in total.
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Tengugurl
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Re: TV RGB mod thread

Post by Tengugurl »

Oh okay :)
Yup the MVS is consolized and the sync from the MVS is just a straight up sync line no resisitors or caps on it. (Later added a 1k Resistor as you had mentioned)

Dang.. I got too impatient! Lol
I will wait for the caps and resisitors to come in from China and get back to you once I get them installed.

Worst part of working on projects, you know?
Last edited by Tengugurl on Tue Jul 16, 2019 10:13 pm, edited 1 time in total.
goldendark007
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Re: TV RGB mod thread

Post by goldendark007 »

Hey all - updates and questions.

I wired up my SCART port and connected pins 17,18, 21, 4, 5, 9, 3, to my chassis ground wire. I have pins 15, 11, and 7 wired to pins 9, 5, 3 with 75ohm resistors. I wired pins 2, 4, 6 together and connected pins 20 and 16 (with a 75ohm resistor) to the ground. I am just trying to make sure I am wiring this correctly. Once it is all set, where do I connect the chassis ground wire to? Is it just the coil running to the tube?


Image
Image

These are the resistors I need to remove/replace. I am assuming I connect to the right sides (closest to the Jungle IC). I see where the RGB channels go and circled them with the appropriate color. When I connect the blanking line can I do the same thing to R802? What value resistor would I use if so?

Image
Image

Lastly, when you refer to connecting sync and audio under the ports, do you just mean the pads that those ports connect to on the PCB? Is this going to alter the results? It would be nice not to have an RCA cable coming out for sync but I dont mind if need be. If I connect the SCART port to the audio pad then connect an external source to the RCA jack(while an RGB SCART source is running with no audio) will it cause any issues?

Thanks so much!!
maxtherabbit wrote:Imagine toggle switch OSD modding a TV in 2019
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Tengugurl wrote:Oh okay :)
Yupn the MVS is consolized and the sync from the MVS is just a straight up sync line no resisitors or caps on it.

Dang.. I got too impatient! Lol
I will wait for the caps and resisitors to come in from China and get back to you once I get them installed.

Worst part of working on projects, you know?
Makes me feel lucky I have an electronics store on my drive to work...

Should need 0.1uF caps on the RGB lines, 75 ohm resistors to ground on the RGB lines for termination. The AV port will have 75 Ohm to ground and caps already on the chassis so won't need any added.

For Jamma attenuation I generally use 500 ohm pots on the RGB lines, 1K resistor on sync. These resistors need to be in line before the RGBS enters the TV and goes past the 75 Ohm termination resistors. Some people have other ideas on how this should be done but I've found this approach to work nicely. If you can't get 500 Ohm pots, resistors somewhere around 360 to 470 ohm should be close, prefer closer to 470 in my experience.
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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 »

goldendark007 wrote:Hey all - updates and questions.

I wired up my SCART port and connected pins 17,18, 21, 4, 5, 9, 3, to my chassis ground wire. I have pins 15, 11, and 7 wired to pins 9, 5, 3 with 75ohm resistors. I wired pins 2, 4, 6 together and connected pins 20 and 16 (with a 75ohm resistor) to the ground. I am just trying to make sure I am wiring this correctly. Once it is all set, where do I connect the chassis ground wire to? Is it just the coil running to the tube?


Image
Image

These are the resistors I need to remove/replace. I am assuming I connect to the right sides (closest to the Jungle IC). I see where the RGB channels go and circled them with the appropriate color. When I connect the blanking line can I do the same thing to R802? What value resistor would I use if so?

Image
Image

Lastly, when you refer to connecting sync and audio under the ports, do you just mean the pads that those ports connect to on the PCB? Is this going to alter the results? It would be nice not to have an RCA cable coming out for sync but I dont mind if need be. If I connect the SCART port to the audio pad then connect an external source to the RCA jack(while an RGB SCART source is running with no audio) will it cause any issues?

Thanks so much!!

Scart pin 20, the Video in or sync in pin, will not require a 75 ohm to ground, there will be one built into the TV near the AV port. Check your schematic/chassis and you will find it.

Ground is all over the place, tuner shields, heat sinks, the outside of AV ports and all over the chassis. You can find it using the multimeter. Just try and stay away from the AC and flyback.

Underneath the AV port there will be solder joints that connect to the signal and ground of the AV port. Use your multimeter to work out which is which, connect your pin 20 to the solder joint that connects to the inside of the AV port.

I think you should be fine with that audio set up you mention.

As for the resistors etc all the appropriate information has been provided at some time in this thread. The rule of thumb for blanking is to use the same value as the one being removed.
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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
Romariu
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Re: TV RGB mod thread

Post by Romariu »

Hi, guys, could you help me with this TV, is it possible to modify it?
The model is this Cph04_Philco.
thank you.
reboot.revival
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Re: TV RGB mod thread

Post by reboot.revival »

Hey guys.

I found the spongebob crt mod over on Tinkerplunk (https://tinkerplunk.com/spongebob-tv-rgb-mod/) who referred me here. My model is slightly different, but the main jungle chip is identical. I am getting some odd results and I cant seem to get anywhere with it. Either I get no video or I get this.

Image.

Sorry about the dark image.

I am using the Insurrection SCART cable for a Model 2 genesis. At first I tried to mix the OSD with the SCART RGB. I did get the OSD but it was black instead of greenish yellow and the rgb images was the same as above. So I removed the OSD all together until I could get a proper signal. Right now the RGB feed from the scart cable is directly fed into a .1uf cap already on the mainboard and then to the jungle. If I attempt to use a 75ohm grounding resistor on the lines, I get no image. If I remove blanking and RGB, I get a normal composite feed. Occasionally depending on whats moving across the screen, I get a pretty decent image for a few seconds. Its still not completely right, but its close. More blues in the right places and stuff like that. But for the most part it just looks like edge detection patterns.

Any Ideas?


Thanks
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LuckyDay
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Re: TV RGB mod thread

Post by LuckyDay »

Tengugurl wrote:Hi everyone!

Here is a video of what I am experiencing in my Obsolete RGB Mod (Aka switch between OSD, Common and SCART - I did this as a POC before I did the Mux method sorry in advance!)
https://youtu.be/uwcunL8VOU0

I want to get the Obsolete method working first as I am still learning all about CRTs and doing this mod.
I'm not sure if it's too late on this, but I would suggest in response to this part of your post that you go with the OSD/Mux current method. These are very easy sets to learn on and do correctly using that method, and think you're doing a disservice to yourself by bothering with the old mod.

Sounds like you've already started, so may not matter now, but just throwing that idea out there.
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vol.2
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Re: TV RGB mod thread

Post by vol.2 »

Thinking about doing an old TV I have hanging around for fun/practice. It's a Toshiba CX1467. There is an on-screen display which I was thinking I could maybe hack. I believe that this is the IC in question: panasonics AN5253N

https://pdf1.alldatasheet.com/datasheet ... 5352N.html

Looks like it accepts Y (which I'm assuming is Luma), b-y, r-y, and g-y.

Can anyone tell me if this is the way to go, if I should go about it in a different way or maybe just skip this one and go for a different set?

Thanks
SEGA-CD
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Re: TV RGB mod thread

Post by SEGA-CD »

Hi everyone, I am looking to RGB mod a Sharp 25R-S100 and need some guidance. Another user on here around page 35 was modding one but never posted the result so I don't know if he ever got it working or not. User MarkOZLAD drew up this diagram for him: https://drive.google.com/file/d/0BxXDEF ... 9kQmc/view

This is the schematic that the user had originally posted https://www.manualslib.com/manual/78077 ... e=4#manual

Those posts were nearly two years ago so I don't know if technique has changed or not and what the current accepted way of RGB modding is. Does the above information remain relevant and useful or is it outdated and should I look elsewhere? Any tips are appreciated, thanks.
Romariu
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Re: TV RGB mod thread

Post by Romariu »

I need help modifying a tv with CI Toshiba TB1238BN.
Could someone please help me.
comp1demon
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Re: TV RGB mod thread

Post by comp1demon »

Any Detailed info on RGB modding with Scart Connector JVC D series TV?
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

SEGA-CD wrote:Hi everyone, I am looking to RGB mod a Sharp 25R-S100 and need some guidance. Another user on here around page 35 was modding one but never posted the result so I don't know if he ever got it working or not. User MarkOZLAD drew up this diagram for him: https://drive.google.com/file/d/0BxXDEF ... 9kQmc/view

This is the schematic that the user had originally posted https://www.manualslib.com/manual/78077 ... e=4#manual

Those posts were nearly two years ago so I don't know if technique has changed or not and what the current accepted way of RGB modding is. Does the above information remain relevant and useful or is it outdated and should I look elsewhere? Any tips are appreciated, thanks.
I’m not sure it can be modded. The jungle appears to be set for digital RGB. It is an equivalent of an LA76843 and they tend to be a family of chips I do t have much luck with.
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undone.evil
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Re: TV RGB mod thread

Post by undone.evil »

hello i hope you guys can help me figure out what the hell im doing.

i have a kv-20s20 and it uses a cxa1870s jungle chip. i had read earlier in this thread that it could not be modded because it is digital well i read that after i started trying to rgb mod it.
i am testing this using a master system and genesis. this tv is odd because i can see the rgb signal on the tv whether i have 5v on the osdblk or not but when there is no 5v the brightness and colors are dim
also i see the menu with or without 5v on osdblk which leads me to believe that the rgb is for closed caption only.

i have been messing with this tv for the better part of a week trying many different configurations but i finally got a decent image after i injected the rgb signal right on the pins of the cc chip so i removed it from that location and injected into an empty header location just before the jungle and tried to simulate the circuit between the cc chip and jungle chip. after experimenting a little more i have a very good image on screen that im happy with.

i have very limited knowledge of electronics but i do know how electricity works and i work on refrigeration equipment so have to deal with high voltages and low voltage control circuits so if you guys could help me understand whats going on here and how i could do it better i would greatly appreciate it. for instance i dont understand what the capacitors going to ground are for in the original circuit, why changing the resistor values on the rgb from the genesis changed color and brightness even though there not ghanging the voltage (im guessing its changing amplitude), or why the sync from the genesis needs a resistor or i just get a black screen.

i drew a diagram of the circuit between the cc chip and jungle chip but the scan is kind of crappy and hard to make out blown up 500% so i could not read the value of some of the components and the values i have could be wrong. there is also some kind of load on the osdblk line after the first resistor but what it is is unreadable in the original diagram. also i imagine that this mod would not work with standard scart cables for these systems seing as they add extra resistors and capacitors in the circuit.

service manual: https://www.manualslib.com/manual/96015 ... 20KV-20S20

jungle chip datasheet: https://pdf1.alldatasheet.com/datasheet ... 1870S.html

here are some pictures of my modifications and the results. thank you.

diagram: https://drive.google.com/uc?export=view ... 9ZOMPiVt9g
image no OSD: https://drive.google.com/uc?export=view ... YRH5_D9myt
image with OSD: https://drive.google.com/uc?export=view ... MVq1lcE3cz
Last edited by undone.evil on Sat Dec 19, 2020 2:09 pm, edited 3 times in total.
skum
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Re: TV RGB mod thread

Post by skum »

Romariu wrote:I need help modifying a tv with CI Toshiba TB1238BN.
Could someone please help me.
Looks simple as such, unless I am mistaking something: Apply more than 2.4V on pin 13 (ensuring proper pulldown and such), and inject RGB on 14, 15, 16 (observe any components that might need to be removed). Put sync into AV pin. Some pictures or more information would of course give more help.
SEGA-CD
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Re: TV RGB mod thread

Post by SEGA-CD »

MarkOZLAD wrote:
SEGA-CD wrote:Hi everyone, I am looking to RGB mod a Sharp 25R-S100 and need some guidance. Another user on here around page 35 was modding one but never posted the result so I don't know if he ever got it working or not. User MarkOZLAD drew up this diagram for him: https://drive.google.com/file/d/0BxXDEF ... 9kQmc/view

This is the schematic that the user had originally posted https://www.manualslib.com/manual/78077 ... e=4#manual

Those posts were nearly two years ago so I don't know if technique has changed or not and what the current accepted way of RGB modding is. Does the above information remain relevant and useful or is it outdated and should I look elsewhere? Any tips are appreciated, thanks.
I’m not sure it can be modded. The jungle appears to be set for digital RGB. It is an equivalent of an LA76843 and they tend to be a family of chips I do t have much luck with.
It's a shame the other user never mentioned anything about whether or not it worked out for him. I would message him but he hasn't logged on since February so he's probably not coming back anytime soon. So digital RGB is a no go? If I did try to modify it and it ends up not working, is it possible to revert it back to stock?
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

SEGA-CD wrote:If I did try to modify it and it ends up not working, is it possible to revert it back to stock?
It depends on the circuits on your set.

I seem to remember something about these sets having jumpers on the RGB and blanking lines but I cannot be sure.

If there are jumpers I would try lifting one end of each jumper so that you take the microcontroller out of the RGB circuit and then feeding 75 Ohm terminated RGB via 0.1uF caps into the circuits and see if it works. If so you can then look at implementing a mux.
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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
SEGA-CD
Posts: 7
Joined: Mon Jul 08, 2019 4:27 pm

Re: TV RGB mod thread

Post by SEGA-CD »

MarkOZLAD wrote: It depends on the circuits on your set.

I seem to remember something about these sets having jumpers on the RGB and blanking lines but I cannot be sure.

If there are jumpers I would try lifting one end of each jumper so that you take the microcontroller out of the RGB circuit and then feeding 75 Ohm terminated RGB via 0.1uF caps into the circuits and see if it works. If so you can then look at implementing a mux.
Okay, I'll have to do some research then. I've grown fond of this TV and despite composite only it doesn't look horrible so it's not a big deal if it can't be modded. I also have an RCA Truflat 20f420t with s-video but it's hard as hell to find schematics and pin outs so I can't be bothered since it's honestly a bit of a junk set.
MarkOZLAD
Posts: 1004
Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

SEGA-CD wrote:Okay, I'll have to do some research then. I've grown fond of this TV and despite composite only it doesn't look horrible so it's not a big deal if it can't be modded
Looks like you can lift the legs of R2024, R2025, R2026 that are FARTHEST from the micro controller to isolate the OSD RGB, use the empty holes to inject 75R terminated/0.1uF capped RGB. For blanking lift the leg of R2027 that is CLOSEST to the micro controller and inject your 5V into the lifted leg.
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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
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