TV RGB mod thread

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MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

It would be very interesting to connect the multimeter to jumper 9253 and ground and measure the voltage when the OSD is on. (With our 5V line disconnected)

If you can't find a voltage that triggers the RGB insertion it may be possible that the micro controller chip is sending a signal to the jungle via the serial communications. If it gets to that point I have some ideas we can try. It will involve snipping the OSD lines by pulling jumpers 9250, 9251 and 9252.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Hmm, interesting, will measure that for sure!
I have 2 potentiometers 1k type b , and another 10k type B also.
The strange thing, i touth the voltage on that pin is low, and think that we have to increase it, and not reduce, but on some threads up Syntax said something about 4v.
Well will definily put a resistor there because it's easier, will get the 1000ohms (1k 1/4w)
And cross the fingers, because now i have to make it happen because the image is so beaultifull!

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

MarkOZLAD wrote:It would be very interesting to connect the multimeter to jumper 9253 and ground and measure the voltage when the OSD is on. (With our 5V line disconnected)

If you can't find a voltage that triggers the RGB insertion it may be possible that the micro controller chip is sending a signal to the jungle via the serial communications. If it gets to that point I have some ideas we can try. It will involve snipping the OSD lines by pulling jumpers 9250, 9251 and 9252.
I just had a thought. I wonder if jumpers 9250, 9251, 9252 and 9253 are supposed to be diodes when an external RGB source is attached.

I've seen that design on other boards.

We could test this by desoldering 9250,9251 and 9252, injecting the rgb and then hitting the menu button.

EDIT: After further investigation I am convinced this is the case. I believe this is what you should be investigating. Could simulate a diode by soldering in wires with quick connects into the 9250, 9251, 9252 and 9253 jumper pins and then test what happens when you connect and disconnect.
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MarkOZLAD
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hi Mark
My only concert, when desolder things, or try to measure voltagem on some tiny spots, i short something and them destroy this good chassi.
Will measure the 5v line that we have today, and those one you suggest for sure.

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hi Mark
My only concert, when desolder things, or try to measure voltagem on some tiny spots, i short something and them destroy this good chassi.
Will measure the 5v line that we have today, and those one you suggest for sure.

Thanks
Marcos
Impossible to attempt these mods without risking losing the chassis. I have done everything I can to prevent that happening.

The 9250, 9251 and 9252 jumpers are just pieces of wire. The OSD sends its signals through them. Instead of desoldering them, you can cut them with clips and you can resolder them later to restore them.

Do not snip 9253, we will use that to get the FBAL signal from the OSD.

Clip 9250, 9251 and 9252, turn the tv on with the VGA RGB and sync signals coming in but the 5V "EXT FBAL IN" disconnected. Then try and bring up the OSD by hitting menu. If my theory is correct you will have your picture.

You won't see an OSD. We will look to restore that later.

EDIT: Snip the jumpers from the topside of the chassis, just cut them in the middle so they no longer make a connection. You will likely solder diodes tobthdm later to get back OSD.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Thank you so much, have no words to express my gratitude, the hekp you are having with me, i'm positive sure we will sucess in this mod!
Will do this on my office is a place better to check those things
Will bring more news on monday!

Thank you so much!
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Thank you so much, have no words to express my gratitude, the hekp you are having with me, i'm positive sure we will sucess in this mod!
Will do this on my office is a place better to check those things
Will bring more news on monday!

Thank you so much!
Marcos
You mean I have to wait till Monday? No fair! :-)

Even worse, it will be Tuesday morning Australian time.

I have enjoyed helping you Marcos. Would love to see this working perfectly.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hi Mark
Hehe, it's because all my tool box stayed on my office!
I'm very excited to see it working too, just for the small areas of the screen i saw, i can see the potential of this mod, because like i said the original tv set with all components made for the specific tube, makes the image totaly awesome. Its very difftent when you have a "generic chassis" adaptable for certain tubes, you will never get the convergence, geometry and colors perfect, but with the original tv brains you will!
By the way i sent you a pm with my 2 machines and my bench test, did you see it ?

Thank you so much!
Marcos
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Thought we established that the f blanking pin on our Brazilian friends set had different settings?

I don't mean to confuse so I'll just type what is do in your situation.

If I find a jungle with dual rgb input like teletext or Pip or some other form of external RGB input I always check the RGB input lines resistance to ground.
If it's 75 ohm I leave it and upgrade the caps only. Usually it will be 100 to 470ohm tho. The 100ohm sets I actually leave 100, something about them it just looks correct. 75 is washed on them.
Many sets with external RGB lines have components removed and these lines terminated. You can fix this and make super neat installs if you follow the traces.

Some sets (I know LG does this) can take RGB in via the component plugs, you only need to wire in sync and it's normally labeled on the board. Super easy addition of a single rca for sync and your done!
These same sets actually wire their rca header via a scart pinout!
So you can desolder the comp header and put a scart one in if you want(be sure to check trace paths still)

I always wire my RGB before wiring blanking, some install methods will not require blanking

I always check the voltage on the blanking pin with the tv on and nothing on screen.
If it shows 0 volts then it only needs voltage.
It may have up to 3 different settings across a voltage range for example Mitsubishi jungles have
Tv sync 0-.2v
Osd sync.2v-3v
Halftone 3-5v
So having a 10k pot is handy to sweep across that voltage range.

Having said that if you check a Mitsubishi jungle fast blanking pin you will find it is sitting high around 5v. The only way to control it is with a voltage divider and the easiest type is a potentiometer.
So in this instance v+ outside leg, f blank center leg, ground outside leg.
When you have the pot in its sweet spot you can measure the resistance between left leg and center, and right leg and center, then use the same value resistors.
I'm a tight ass and I don't like leaving pots floating inside sets so I do this.
One resistor ground the other v+ twist them together and solder to the f blank.
9 time out of 10 this is only required an OSD hack.

It's also a very useful method to use on a Sony jungle with L2Fil pin. You can apply voltage this way and move the screen left or right.
Because different consoles seem to always have different centering I tend to leave the l2fil pot externally mounted and powered from the console.
So when you plug in RGB it centers close and you can adjust.
This way you don't screw with your composite or component centering.

Some sets actually center RGB fine if you sync on composite green.


10k pot is more than enough for any job we do in these tv's. Buy a few they are handy.

Your mod so far is fine you just haven't found the correct blanking pin or you have the correct one but wrong voltage.. So you can only see the picture via the menu blanking.

Follow my above instructions and you should be able to figure out if it needs a voltage divider or just voltage.

Great to see others progress!
Last edited by Syntax on Sun Sep 03, 2017 8:46 am, edited 2 times in total.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Syntax wrote:Thought we established that the f blanking pin on our Brazilian friends set had different settings?

I don't mean to confuse so I'll just type what is do in your situation.

If I find a jungle with dual rgb input like teletext or Pip or some other form of external RGB input I always check the RGB input lines resistance to ground.
If it's 75 ohm I leave it and upgrade the caps only. Usually it will be 100 to 470ohm tho. The 100ohm sets I actually leave 100, something about them it just looks correct. 75 is washed on them.

I always wire my RGB before wiring blanking, some install methods will not require blanking

I always check the voltage on the blanking pin with the tv on and nothing on screen.
If it shows 0 volts then it only needs voltage.
It may have up to 3 different settings across a voltage range for example Mitsubishi jungles have
Tv sync 0-.2v
Osd sync.2v-3v
Halftone 3-5v
So having a 10k pot is handy to sweep acr9ss that voltage range.

Having said that if you check a Mitsubishi jungle fast blanking pin you will find it is sitting high around 5v. The only way to control it is with a voltage divider and the easiest type is a potentiometer.
So in this instance v+ outside leg, f blank center leg, ground outside leg.
When you have the pot in its sweet spot you can measure the resistance between left leg and center, and right leg and center, then use the same value resistors. I'm a tight ads and I don't like leaving pots floating inside sets so I do this.
One resistor ground the other v+ twist them together and solder to the f blank.
9 time out of 10 this is only required an OSD hack.


10k is more than enough for any job we do in these tv's.

Your mod so far is fine you just haven't found the correct blanking pin. So you can only see the picture via the menu blanking.
I'd say you just need to give the menu blank pin a few more volts.

Also stop trying to source power from external sources.
The tv has more than enough for you to use and will cause far less interference. Learn how to properly wire a 10k pot and you'll be set.
External power should only be wired from console to scart for auto blanking and horizontal fine tuning.


Great to see others progress!
Right now I'm not concerned about blanking voltages. We'll get to that in time. For now we can just press menu to get it to blank.

It is my firm belief that the chassis is missing a set of diodes that would be installed if the set was going to use the external RGB Port. If you check the chassis schematics and compare to other sets where there are similar RGB lines that are shared between two RGB sources, there are always diodes in place to prevent the signals from feeding back into each other. This set just has jumpers in place where there would be diodes if the external RGB was going to be used. Thus the weird feedback muxing.

The plan is to clip the jumpers that sit in place of diodes on the OSD lines, leaving the jumper in place for OSD blanking. Then feed the RGB in, without the 5V blanking and press the MENU. The OSD lines will be clipped so only the external RGB feed will come in and there won't be any feedback.

By clipping the jumpers we make a "zero way" connection. It's the next best thing to a one way diode!

If it works we can look at installing diodes and then getting the blanking setup correct.

Oh I have told Marcos numerous time to use the internal 5V not an external PSU. He does seem to revert to it a lot!
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

The external RGB lines should not be shared and if they are it's with some thing you don't need.

If you are worried then cut the traces to the external RGB and wire directly to it with caps and resistors.
Diodes are not needed.

The problem is blanking. You seem to only be blanking via menu. You can't use the menu blanking for RGB unless you are going for an OSD hack.

You may need to cut the blanking and make a switch but at that point it's pretty much an OSD hack.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Syntax wrote:The external RGB lines should not be shared and if they are it's with some thing you don't need.

If you are worried then cut the traces to the external RGB and wire directly to it with caps and resistors.
Diodes are not needed.

The problem is blanking. You seem to only be blanking via menu. You can't use the menu blanking for RGB unless you are going for an OSD hack.

You may need to cut the blanking and make a switch but at that point it's pretty much an OSD hack.
Ok, have had a bit of time to think...

If I had've foreseen the issues with the missing diodes I would've gone with a straight OSD hack.

I believe that without the diodes in place we in fact now have two issues. A blanking signal feedback issue and a feedback issue on the RGB lines. In all the chassis I've seen before the diodes were in place and I didn't encounter the issue.

I still think we go ahead with the addition of the diodes to fix it in the completed solution and in the interim snip the RGB jumpers and use the menu blanking to at least see full screen RGB in action whilst we await addition of diodes.
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

I have never used diodes for any mods.
My whole RGB kit consists of 4 core shielded cable, 4pole switches, 100n monolithic caps, 75ohm resistors, 10k pots and some female scart connectors

Had no problems yet with dual RGB input setups.

All Marcos has to do is find the correct pin for blanking and everything will be fine.

That interference is his injected 5v on the osd blanking line screwing things up.
Cut the 5v Marcos and watch it clear up.
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Re: TV RGB mod thread

Post by MarkOZLAD »

Syntax wrote:I have never used diodes for any mods.
My whole RGB kit consists of 4 core shielded cable, 4pole switches, 100n monolithic caps, 75ohm resistors, 10k pots and some female scart connectors

Had no problems yet with dual RGB input setups.

All Marcos has to do is find the correct pin for blanking and everything will be fine.

That interference is his injected 5v on the osd blanking line screwing things up.
Cut the 5v Marcos and watch it clear up.

It's only a single RGB input Jungle.

Numbski is the person who reported interference. Are you confusing these two again?
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

MarkOZLAD wrote:
Syntax wrote:I have never used diodes for any mods.
My whole RGB kit consists of 4 core shielded cable, 4pole switches, 100n monolithic caps, 75ohm resistors, 10k pots and some female scart connectors

Had no problems yet with dual RGB input setups.

All Marcos has to do is find the correct pin for blanking and everything will be fine.

That interference is his injected 5v on the osd blanking line screwing things up.
Cut the 5v Marcos and watch it clear up.

It's only a single RGB input Jungle.

Numbski is the person who reported interference. Are you confusing these two again?

Yes lol, oh man sorry. If its only single just cut the traces near the jungle and make a 4pdt switch and correct voltage to blanking right?
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Re: TV RGB mod thread

Post by MarkOZLAD »

Syntax was right. The issue was the blanking voltage. We got it working tonight. I'm sure Marcos will share pictures when he can. Fantastic picture quality!
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Everyone !
This is a good news thread ! With a successful Rgb Mod
Firstly want to thanks all the envolved people that helped with hints and tips, but the special thanks goes to Mark, without him this mod will not suceed, he provides so much detailed information, from where to get the right connections, and help me sometimes to avoid loose the chassi with precious information. Will try to describe bellow, and try to update this thread once on a while if i forgot something to help another guys that should have the same TV set i have.

So this mod were made onto a TV 21" Philips 21Gx1669/78r, Mark has found a very easy way to inject the rgb signal direct onto a "NOTUSED J281" port on the board, some kind of sleep port, so spare me from lift the tiny legs directly on the chip, turn a much easy task to do, this particular J281 has all the inputs you will need (red, green, blue, gnd, and f blank) the sync was get from the AV port.

You will need:
2 pçs = 1k ohms 1/4w
3 pçs = 75ohms 1/4w
1 pot = 10k type B
Vga cable (in my case used a Revenge from Mars db15 male on one point and a pin 10 wells garner default, on the other point)
Remember this mod will work only if you have a PC, with already 15khz output, i used an ATI 5450 patched, Winxp 32bit + CRT_Emudriver + Groovymame (crt special version)

You will need to run the sync from the vga (h and V), and before twist them you will need to install a 1k resistor in each wire, them twist and wire to the AV connector central pin, grounded 3 resistor 75ohms in each color with the same gnd that goes to pin 1 J281
On the middle of the process we change the 5v source, not anymore from J390 pin 3, and now from the BC337 7290 transistor leg "C" this one provides the right stabble 5v we needed.
But when turn on the tv, ,the screen goes black, so we need to add a potentiometer 10k type B, on any external leg you put the 5v source, and in the middle leg you install the wire that will go to the F Blank (purple wire).

I have a google drive with all test and photos so people can see what i´v done, and will update this album with frequency, so stay tunned!

https://photos.app.goo.gl/ROlDzMpabIOwCrV42

Sorry for some mistakes on English write and specialy on speach, lol

Now will restore the OSD wires cutted so i can adjust the vertical size, and horizontal position of the picture thru the service menu.
Things to to in the future:
- Replace those fast connectors with better shield wires, those installed are so thin, have to put some shield wires because a little bit interferance appears sometimes, just on solid colors background you see that, but nothing that overcome the beaulty of the picture.
- Maybe rip off one side of a VGA quality cable an solder direct those wires in the board, take off all crapy low quality wires, with already on vga cable ones, to avoid any kind of interferance.

And Mark thank you again my friend!
Marcos
Last edited by m.andrade1 on Wed Sep 06, 2017 7:23 pm, edited 6 times in total.
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Pikkon
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Re: TV RGB mod thread

Post by Pikkon »

On my rgb modded sony trinitron the picture is awesome but I have the crank the brightness down a good amount for it to look better but then it effects my other consoles as they end up way to dark.

Is there anything I can add that can decrease the brightness in the mod,was thinking maybe some potentiometers.
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Re: TV RGB mod thread

Post by MarkOZLAD »

Ok you can now go back to listing my LG CA-20F80/MC-84A chassis mod as successful again! I found some missing components, soldered them in and it worked!

Details have been updated in thread LG CA-20F80/Chassis MC84A RGB Scart Mod Almost complete...

For people looking for a shortcut to RGB modding this could be the answer for them. Just install a scart port, replace some missing components and change the service menu and you are done.

While I'm here I'd just like to say to Marcos that I really enjoyed helping him with his Phillips 21GX1669 mod. I am still learning a lot about this stuff and going through that process has taken me to another level. It turns out the Jungle I/C on his TV was identical when it came to RGB blanking and this gave me the encouragement to revisit my TV. Marcos said getting my TV working was my reward for helping him and I tend to agree. That and a new friend.
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Re: TV RGB mod thread

Post by buttersoft »

Pikkon wrote:On my rgb modded sony trinitron the picture is awesome but I have the crank the brightness down a good amount for it to look better but then it effects my other consoles as they end up way to dark.

Is there anything I can add that can decrease the brightness in the mod,was thinking maybe some potentiometers.
Just a thought, but does your Jungle IC want 0.7Vp-p or lower, like 05Vp-p?
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Re: TV RGB mod thread

Post by MarkOZLAD »

buttersoft wrote:
Pikkon wrote:On my rgb modded sony trinitron the picture is awesome but I have the crank the brightness down a good amount for it to look better but then it effects my other consoles as they end up way to dark.

Is there anything I can add that can decrease the brightness in the mod,was thinking maybe some potentiometers.
Just a thought, but does your Jungle IC want 0.7Vp-p or lower, like 05Vp-p?
Generally the Sony's are 0.7Vp-p. The ones I've modded I've noted the exact same behaviour, definitely brighter from the RGB mod input than when I switch back to composite.

Not sure what the answer is. I did decrease the screen voltage on mine, this decreases the RGB brightness but the composite has the same corresponding change so doesn't solve the issue.
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Re: TV RGB mod thread

Post by Syntax »

MarkOZLAD wrote:
buttersoft wrote:
Pikkon wrote:On my rgb modded sony trinitron the picture is awesome but I have the crank the brightness down a good amount for it to look better but then it effects my other consoles as they end up way to dark.

Is there anything I can add that can decrease the brightness in the mod,was thinking maybe some potentiometers.
Just a thought, but does your Jungle IC want 0.7Vp-p or lower, like 05Vp-p?
Generally the Sony's are 0.7Vp-p. The ones I've modded I've noted the exact same behaviour, definitely brighter from the RGB mod input than when I switch back to composite.

Not sure what the answer is. I did decrease the screen voltage on mine, this decreases the RGB brightness but the composite has the same corresponding change so doesn't solve the issue.
It's as simple as increasing the value of the termination resistors.
These Sony's seem to look better with 100ohm resistors instead of 75ohm.
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soviet9922
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Re: TV RGB mod thread

Post by soviet9922 »

Hi guys im hacking rgb into a jvc tm-h150cg.
Need to get into service mode if someone knows how ?.
Also the service manual could be great if somebody know where to download it ?.
I'm documenting the process here http://shmups.system11.org/viewtopic.php?f=6&t=60736
Also going to do a 17" chasis jvc next the guts look almost the same.
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Re: TV RGB mod thread

Post by MarkOZLAD »

Syntax wrote:
It's as simple as increasing the value of the termination resistors.
These Sony's seem to look better with 100ohm resistors instead of 75ohm.
Cheers for another great tip. Will give that a shot on the Sony TV I will mod this weekend.
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

MarkOZLAD wrote:
Syntax wrote:
It's as simple as increasing the value of the termination resistors.
These Sony's seem to look better with 100ohm resistors instead of 75ohm.
Cheers for another great tip. Will give that a shot on the Sony TV I will mod this weekend.

I should of asked if its just this tv thats being bright for you or if you use more than 1 console on it via RGB.

Could always be the console or the cable not having proper 75ohm terminations. Plug in the cable to the console(turned off) and check the scart end RGB lines to ground for 75ohm.

But if you have a few RGB consoles and a few RGB tv's and this Sony is the only one being a bitch then increase them terminations.
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Re: TV RGB mod thread

Post by Pikkon »

Thank's for the info Syntax,will definitely give this a try.

With using my snes,genesis and saturn they were all way to bright and the rgb cables are wired correctly.
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Re: TV RGB mod thread

Post by nakedarthur »

I finally got together with the TV tech tonight and I'm happy to report the KV-27S42 was successfully modded. Amazingly, it worked on the first try! Huge props to everyone for the great information here and thanks to MarkOZLAD for answering my questions. I posted a small gallery on imgur here, including an updated diagram of some of the things I was questioning.
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Re: TV RGB mod thread

Post by MarkOZLAD »

nakedarthur wrote:I finally got together with the TV tech tonight and I'm happy to report the KV-27S42 was successfully modded. Amazingly, it worked on the first try! Huge props to everyone for the great information here and thanks to MarkOZLAD for answering my questions. I posted a small gallery on imgur here, including an updated diagram of some of the things I was questioning.
Glad it worked. Pleased to help.
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Re: TV RGB mod thread

Post by nakedarthur »

I ran into one slight hitch after getting the TV into my setup. Genesis, SNES, PS1, Saturn, PC Engine, and even my GroovyMAME machine all work perfectly, but having a little trouble with my NESRGB. It has one of the 3d printed ports with the SNES style connectors, so I got one of retro_console_accessories pro coaxial SNES cables for it. It worked fine on my previous setup, but with the modded TV I'm getting a very dim pictures in bright scenes. Strangely, it seems to work perfectly on the darker ones..

Edit: Looks like SNES cables have 220uf capacitors in line, guessing that's not playing too well with the other caps..

Edit2: Removed the 220uf caps from the Scart head but it still looks the same..

Image
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

For nes rgb cables make sure there are no components inline. Nothing but wires. All resistors, terminations and caps are in the NES.

That picture has me stumped tho. Maybe Tim has seen it before.
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