TV RGB mod thread

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m.andrade1
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Joined: Thu Aug 24, 2017 11:43 am

Re: TV RGB mod thread

Post by m.andrade1 »

Hello Everyone !
I will try the RGB mod in a Philips 21" 21Gx1669/78r the Chassis is a GR6-AL, but this model has 2 main chips inside, a Sanyo 7345 and another 7271, seems both chips has RGB inputs but which one of them is the right one to apply the signal ?
The source signal will came from a compluter thru VGA port with an ATi 5450 already patch with 15khz, today i´m using a J-pac with a Eletrocyan (Brazilian arcade monitor) but i´m trying to improve the image qualitity with this mod.

The chip information are informed on pages 26 and 27

Service manual:
https://www.electronica-pt.com/esquema/ ... no_html,1/

Here are some pics from the tv and chassi:
https://goo.gl/photos/DBKU2Vhvforwoatf9

Any help will be very apreciated.
Thanks Marcos
Last edited by m.andrade1 on Thu Aug 24, 2017 2:12 pm, edited 2 times in total.
m.andrade1
Posts: 39
Joined: Thu Aug 24, 2017 11:43 am

Re: TV RGB mod thread

Post by m.andrade1 »

Hello Everyone !
I will try the RGB mod in a Philips 21" 21Gx1669/78r the Chassis is a GR6-AL, but this model has 2 main chips inside, a Sanyo 7345 and another 7271, seems both chips has RGB inputs but which one of them is the right one to apply the signal ?
The source signal will came from a compluter thru VGA port with an ATi 5450 already patch with 15khz, today i´m using a J-pac with a Eletrocyan (Brazilian arcade monitor) but i´m trying to improve the image qualitity with this mod.

The chip information are informed on pages 26 and 27

Service manual:
https://www.electronica-pt.com/esquema/ ... no_html,1/

Any help will be very apreciated.
Thanks Marcos
foldor
Posts: 2
Joined: Wed Aug 23, 2017 7:23 pm

Re: TV RGB mod thread

Post by foldor »

MarkOZLAD wrote:
mikejmoffitt wrote:I don't want to speak ill of that guide or its maker, but you should not be feeding RGB directly to the neck board unless you have exhausted all other options and are sure there is no point of injection prior.

In the case of the mid-nineties and 2000s-era Trinitron sets, the jungle's OSD RGB inputs should be more than adequate and not rely on such a relatively complicated circuit.

Check out the first post of this thread for references to other similar sets that have been successfully modified.

In that guide, it looks terrible too. Look at this picture: http://i.imgur.com/IXYQAOn.jpg
Had a quick look at the schematics. I don't think this TV can be OSD RGB modded. The chassis doesn't have a seperate micro controller and jungle chip. Just a single do everything chip.

Seems to me this one is a job for a Shinybow SB-2840.
Yeah, I did notice that I couldn't find an OSD, and was wondering if it was just because I didn't know where to look or not. Turns out, I've found the data sheet for the all in one chip it has. This confirms the suspicions that there is no easy method of OSD injecting.
mikejmoffitt wrote:In that guide, it looks terrible too. Look at this picture: http://i.imgur.com/IXYQAOn.jpg
To be fair to those images, he did mention that he was still getting shadowing from the composite inputs he sued as sync, which is why I was looking at adding a sync stripper to remove that effect.

But all in all, most people here aren't thinking there's another way to do this then? If so, that's fine by me, I do understand the suggestion to go for a Shinybow, but I'd like to at least attempt to do an RGB mod on this first. If only because I'm interested in it as a fun project.
snappleman
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Re: TV RGB mod thread

Post by snappleman »

snappleman wrote:I've been reading through this topic and it's got an insane amount of info, but I'm trying to do something a little different that I'd like some help with. I have a cheapo little Durabrand DWT1905 tv that only supports composite and RF inputs. The TV is the basically the same model as the ST419E with a few different components, so I'm using the ST419E manual for reference. I have another TV that has RGB so I don't need RGB on this one, but I do need to use some S-Video sources on it,

The IC that seems to do all the video processing is referenced as M61271M8-058FP-71, which I can't find anything for online, aside from another TV that uses it which showed pins 29 and 30 as the chrominance signal input and luminance signal input respectively (which in the manual for my TV say Not Used).

The video IC supports S-Video input but there's no S-Video connector on the board. Is it possible for me to just solder directly to the Chroma and Luma pins on the IC (grounding it to the composite video ground maybe?) and feed it an S-Video signal? Would I even be able to switch to it?

Just to update myself, I went ahead and soldered an svideo connector to the luma+chroma+ground. I went into the service menu of the TV and noticed it let me change the AV settings from 1-3 inputs, the third being labeled Component. The component video is actually what the svideo is displaying on, and it works well only with my Saturn. Every other console looks completely off on it (very similar symptoms to how a bad capacitor in the horizontal section looks).

Do I need to put a resistor and capacitor into the circuit to smooth it out? I know that some consoles need special S-video cables with these built in.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Everyone !
I will try the RGB mod in a Philips 21" 21Gx1669/78r the Chassis is a GR6-AL, but this model has 2 main chips inside, a Sanyo 7345 and another 7271, seems both chips has RGB inputs but which one of them is the right one to apply the signal ?
The source signal will came from a compluter thru VGA port with an ATi 5450 already patch with 15khz, today i´m using a J-pac with a Eletrocyan (Brazilian arcade monitor) but i´m trying to improve the image qualitity with this mod.

The chip information are informed on pages 26 and 27

Service manual:
https://www.electronica-pt.com/esquema/ ... no_html,1/

Any help will be very apreciated.
Thanks Marcos
The chip labelled "7271" is actually a Phillips TDA8374A. It is the Jungle Chip and will receive the RGB signal through pins 23,24,25 and blanking on 26. The datasheet is here

The chip with label "7345" is a Sanyo LC864132. It is the micro controller. It generates the On Screen Display and sends it out as RGB through pins 27,28,29 with the blanking signal on pin 30. Datasheet here.

Looking through the schematics of the set it looks like it may be possible to inject the RGB and blanking into the J281 port through pins 5,4,3 and 2 "EXT RED IN", "EXT GREEN IN", "EXT BLUE IN" and "EXT FBAL IN". You may have to desolder under J281 and insert your own pins. On page 27 of the 21gx1669.pdf if you follow the trace lines from the TDA8374A RGB and Blanking pins you'll see what I mean. It says "J281 NOTUSED". Perhaps you can use it instead of snipping the OSD's RGB circuits.

EDIT: I noticed your post where you had photos attached. J281 is clearly visible on the photos. It is just holes and they will have been filled with solder underneath. You can desolder underneath it and push jumper wires in from the top and solder in at the bottom. There is a little 1 and a little 9 printed on the board to let you work out the pin numbers. You can grab ground from here too from pin 1. After that all you should need to find is a 5V source. There are a couple of 5V regulators shown on page 25 of the service manual. Use the output of one of those.


Good luck.
Last edited by MarkOZLAD on Fri Aug 25, 2017 1:49 am, edited 1 time in total.
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MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

foldor wrote:But all in all, most people here aren't thinking there's another way to do this then? If so, that's fine by me, I do understand the suggestion to go for a Shinybow, but I'd like to at least attempt to do an RGB mod on this first. If only because I'm interested in it as a fun project.
Perhaps find another set to play with instead of hacking up this beauty. I started on a Trinitron I found on the side of the road.
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"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
m.andrade1
Posts: 39
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Thank you so much for your help!
In fact your idea is fantastic, if this J281 port is some sort of backup connection for a rgb entrace or maybe a future plain from philips to create a possible video component port it will be much more easy to inject the signal there, than lift up the leg of the chip.
Probally those "EXT" means external, looks like its was made for the RGB mod!
Only a doubt, these "FBal In" is where the 5volts will be inject? Can i run a wire from the positive wire (red) from the Atx power supplier and solder on this point?
Today i'm using a pc with Crt Emudriver + Ati 5450 + Jpac + Brazilian Arcade Monitor + Groovymame

Taking off the arcade monitor chassis will leave a single conector with 5 pins (red,green,blue, Gnd, Sync (h+v togheter)
The colors will be easy, the sync will get from the AV port and the gnd will get on the Neck Board only the "f bal" will be the trick one.

The other scnerario i have is: Crt Emudriver + Ati 5450 already patched with 15khz + vga cable (from a Revenge from Mars pinball) with 10 pins on the end (Well's Gardner default) type, do you think the 5volts could be taken from pin 9?

Will definely take some nice pictures from the board up and down so other fellow users that have the same tv cold benefit from that too.

Thanks you so much Mark for your help and congrat for your knowlead!
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Thank you so much for your help!
In fact your idea is fantastic, if this J281 port is some sort of backup connection for a rgb entrace or maybe a future plain from philips to create a possible video component port it will be much more easy to inject the signal there, than lift up the leg of the chip.
Probally those "EXT" means external, looks like its was made for the RGB mod!
Only a doubt, these "FBal In" is where the 5volts will be inject? Can i run a wire from the positive wire (red) from the Atx power supplier and solder on this point?
Today i'm using a pc with Crt Emudriver + Ati 5450 + Jpac + Brazilian Arcade Monitor + Groovymame

Taking off the arcade monitor chassis will leave a single conector with 5 pins (red,green,blue, Gnd, Sync (h+v togheter)
The colors will be easy, the sync will get from the AV port and the gnd will get on the Neck Board only the "f bal" will be the trick one.

The other scnerario i have is: Crt Emudriver + Ati 5450 already patched with 15khz + vga cable (from a Revenge from Mars pinball) with 10 pins on the end (Well's Gardner default) type, do you think the 5volts could be taken from pin 9?

Will definely take some nice pictures from the board up and down so other fellow users that have the same tv cold benefit from that too.

Thanks you so much Mark for your help and congrat for your knowlead!
I have just edited my post, you should recheck.

I would hook a wire from the output of the 5V regulator on the TV chassis to an on/off switch and then into the "Fbal in". I know Mike uses a pull-up resistor to do this job, maybe he can help tell you how to do that.
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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 again!
I think the 5v have to be switched otherwise will have no OSD, that is the purpose of the switch?

Thanks
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Thank you so much again!
I think the 5v have to be switched otherwise will have no OSD, that is the purpose of the switch?

Thanks
Marcos
The switch allows you to turn RGB mode on and off. From my experience in these situations OSD will work when RGB is on but will be washed out/faded.
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glaysonmestre
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Re: TV RGB mod thread

Post by glaysonmestre »

Can I do this around here?



if it is possible how do I connect an emulator running at 15 Hz on it? please send me tutorial links, I'm not familiar with English the translator is not helping me


Image

model LG CP-29K35A , 29 inch

Image
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
How are you, hope you are fine !
Got it ! Do you think the switch On/Off is necessary just for the 5v (Fbal In) ? Can the other connections stay constant connected into the j281 without a switch ?

Let me show another pictures from the chassi:
https://goo.gl/photos/6qWn5UUHANeVmudT6

You were absolute right, the J281 is a empty connector with just solder underneath, will be a piece of cake to solder the connection from the bottom, my only doubt is the 5v, i saw on the 25 pag manual, some point to catch the 5v, but i kind lost on the schematics, do you think if i get it from the ATX power supplier will be any issue for the mod, its a very good power supplier a corsair 430cx with very solid voltages.
If you could point me a place on the chassi where i could get the 5v will be very appreciated.

Thanks a lot again!
Marcos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
How are you, hope you are fine !
Got it ! Do you think the switch On/Off is necessary just for the 5v (Fbal In) ? Can the other connections stay constant connected into the j281 without a switch ?

Let me show another pictures from the chassi:
https://goo.gl/photos/6qWn5UUHANeVmudT6

You were absolute right, the J281 is a empty connector with just solder underneath, will be a piece of cake to solder the connection from the bottom, my only doubt is the 5v, i saw on the 25 pag manual, some point to catch the 5v, but i kind lost on the schematics, do you think if i get it from the ATX power supplier will be any issue for the mod, its a very good power supplier a corsair 430cx with very solid voltages.
If you could point me a place on the chassi where i could get the 5v will be very appreciated.

Thanks a lot again!
Marcos
If you're never going to turn RGB off you won't need a switch, just permanently connect the 5V line to the FBAL pin. The RGB lines wouldn't need to go through a switch even if you wanted to turn off RGB. You could just unplug scart or turn off the device.

You can find the schematic here. Just wait for about a minute and "Get Manual" will appear.

I was checking out your photos earlier and I did find a 5V regulator. If you look at page 25 of the service manual you will find
items 7290 and 7467, which is a BC337 type transistor. I was able to locate them in the photos you provided. The transistors all look like black half circles from abovewith E C B writtennear them. Could connect to the "E" of either of these transistors. 7290 is near the TV tuner. 7467 is near the two black things marked as fuses.

I'm not sure if it would work to connect to an external power supply.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Excelent! I just located the 7290, so just need to solder a wire on the "E" leg underneath, and them put a switch on/off on the way and on the final end goes to the "Fbal in" on the J281.
I feel very confident now after your explanations! I think it will work!
Will start the RGB mod journey! And will post the results here!

Thank you so much Mark
Marcos
m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Just find a curious think, the 7467 has the default layout with the flat side point up, we got on the right "C" , middle "B" and on the left "E" , seems the most transistor on the board has this layout, but with the 7290, it´s opposite, the "E" is on the right, and the "C" is on the left, with the flat side point up, strange don´t you think, well i will consider the 7467, because it follows the default layout most find on google images i´ve saw on web.

Edit: Now the bizzare thing underneath 7467 is opossite. Do you think it´s a silkscreen issue on the board, now the only that really matchs is the 7290, both sides of the board right is "E", but the layout is not the default from the most BC337 on the board.

What do you think should do now.

https://goo.gl/photos/3TEyFmNexm9kzCiU8

Thanks
Marccos
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Just find a curious think, the 7467 has the default layout with the flat side point up, we got on the right "C" , middle "B" and on the left "E" , seems the most transistor on the board has this layout, but with the 7290, it´s opposite, the "E" is on the right, and the "C" is on the left, with the flat side point up, strange don´t you think, well i will consider the 7467, because it follows the default layout most find on google images i´ve saw on web.

Edit: Now the bizzare thing underneath 7467 is opossite. Do you think it´s a silkscreen issue on the board, now the only that really matchs is the 7290, both sides of the board right is "E", but the layout is not the default from the most BC337 on the board.

What do you think should do now.

https://goo.gl/photos/3TEyFmNexm9kzCiU8

Thanks
Marccos
The datasheet for the BC337 Transistor is here.

Are you sure the transistors aren't oriented differently? Definitely the same way up when you view from above?

I know it's easy to get confused with this stuff, happens to me all the time. Sometimes good just to take a break and walk away and think about it.

If need be you could reassemble the set and connect a multimeter to test voltage.

Another option may be to solder to Pin 12 of the TV tuner.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Absolute sure! You can check the last google photos link.
On both cases 7290 the "E" is in the right side, on the part side and solder side too.
The strange is the 7647, on the part side the "E" is the left side, and on the solder side the "E" is on the right side, very strange!
But i think will get the 5v from the 7290 because they match the sides, only the strange thing that this specific transitor dont follow the default layout, beeing the "E" on the left side.

But i'm very confident, just that last doubt makes me confused.
The photos on the last tread show very clearely the board.

Thanks a lot
Marcos
Last edited by m.andrade1 on Sat Aug 26, 2017 10:27 am, edited 1 time in total.
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glaysonmestre
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Re: TV RGB mod thread

Post by glaysonmestre »

I found this here on the neckboard, and now? how do I connect a supernintendo(SNES) here ?? I have supernintendo but I have no rgb type cable my super nintendo is disassembly as I connect the wires right inside it with solder and I make a cable would have how to do it? Image Image
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Re: TV RGB mod thread

Post by MarkOZLAD »

glaysonmestre wrote:I found this here on the neckboard, and now? how do I connect a supernintendo(SNES) here ?? I have supernintendo but I have no rgb type cable my super nintendo is disassembly as I connect the wires right inside it with solder and I make a cable would have how to do it?
If you want help on this forum please provide the model number of the set and exactly what you want to do. Do you want Scart RGB connection?

This is not an easy task and requires some hard work and study on your part. We are not here to do this for you. Please learn the layout of your chassis schematic, take photos of the board.

DO NOT SOLDER WIRES DIRECTLY TO THE NECKBOARD.
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glaysonmestre
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Re: TV RGB mod thread

Post by glaysonmestre »

MarkOZLAD wrote:
glaysonmestre wrote:I found this here on the neckboard, and now? how do I connect a supernintendo(SNES) here ?? I have supernintendo but I have no rgb type cable my super nintendo is disassembly as I connect the wires right inside it with solder and I make a cable would have how to do it?
If you want help on this forum please provide the model number of the set and exactly what you want to do. Do you want Scart RGB connection?

This is not an easy task and requires some hard work and study on your part. We are not here to do this for you. Please learn the layout of your chassis schematic, take photos of the board.

DO NOT SOLDER WIRES DIRECTLY TO THE NECKBOARD.



Here is the TV model lg rp 29fa35a ,On her board there is no rgb input on the chip i just found rgb written on the neckboard


I wonder if I would break the original input wires back of the neckboard and use mine to send some super nintendo signal, would it work?

do not care if the tv does not work anymore, I want to use it just to play
I'm researching a lot, but here in Brazil there's nothing about very little, so I'm here using a translator to talk, whenever we need help, people think we're lazy, I've been trying for a long time, not expecting anything easy, I just want The correct direction of what I have to do or search, I studied the TV board, there is no rgb input on any chip. I just found it on the neckboard.
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Re: TV RGB mod thread

Post by MarkOZLAD »

glaysonmestre wrote:
MarkOZLAD wrote:
glaysonmestre wrote:I found this here on the neckboard, and now? how do I connect a supernintendo(SNES) here ?? I have supernintendo but I have no rgb type cable my super nintendo is disassembly as I connect the wires right inside it with solder and I make a cable would have how to do it?
If you want help on this forum please provide the model number of the set and exactly what you want to do. Do you want Scart RGB connection?

This is not an easy task and requires some hard work and study on your part. We are not here to do this for you. Please learn the layout of your chassis schematic, take photos of the board.

DO NOT SOLDER WIRES DIRECTLY TO THE NECKBOARD.



Here is the TV model lg rp 29fa35a ,On her board there is no rgb input on the chip i just found rgb written on the neckboard


I wonder if I would break the original input wires back of the neckboard and use mine to send some super nintendo signal, would it work?

do not care if the tv does not work anymore, I want to use it just to play
I'm researching a lot, but here in Brazil there's nothing about very little, so I'm here using a translator to talk, whenever we need help, people think we're lazy, I've been trying for a long time, not expecting anything easy, I just want The correct direction of what I have to do or search, I studied the TV board, there is no rgb input on any chip. I just found it on the neckboard.
Does this TV have component inputs? Easy to just get a Shinybow SB2840.

If you are determined to RGB mod...

Service Manual is here.

The first thing you can try is de-soldering the AV1 jacks and soldering in a scart port into the JK201 jack. Then change the service menu to enable Scart.

If that doesn't work, can try something else.
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Re: TV RGB mod thread

Post by glaysonmestre »

I already have the service manual of the tv, it seems to have several cards I did not understand very well the tv has input component, but component is diferent of rgb? I want to connect a pc to 15 khz, see the service manual that strange seems to have various circuit boards

see pdf online view >>> https://www.docdroid.net/LCRCvtR/lg-rp- ... 29k35a.pdf
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Re: TV RGB mod thread

Post by MarkOZLAD »

glaysonmestre wrote:I already have the service manual of the tv, it seems to have several cards I did not understand very well the tv has input component, but component is diferent of rgb? I want to connect a pc to 15 khz, see the service manual that strange seems to have various circuit boards

see pdf online view >>> https://www.docdroid.net/LCRCvtR/lg-rp- ... 29k35a.pdf
If the TV has component inputs you just need a Shinybow SB2840 RGB Scart to Component converter. It will accept 15Khz RGBS and convert it to 15Khz Component (YUV) which your TV will accept. There will be very little, if any, quality loss.

VGA To Scart Wiring.
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m.andrade1
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Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
How are you! Hope you are fine!
Today i tested the voltagem point 7290, on the "E" point, so what i did, i put the meter on DCV, the black lead on the GND from the neck board, and the red lead on the "E" point of the 7290, the meter shows a floating voltagem from 5,00 to 6,00 tops, but with negative reading, ex: -5,00v, is it right, i´m doing something wrong ? supposed to be 5,00v (positive)

Thanks a lot
Marcos
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Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
How are you! Hope you are fine!
Today i tested the voltagem point 7290, on the "E" point, so what i did, i put the meter on DCV, the black lead on the GND from the neck board, and the red lead on the "E" point of the 7290, the meter shows a floating voltagem from 5,00 to 6,00 tops, but with negative reading, ex: -5,00v, is it right, i´m doing something wrong ? supposed to be 5,00v (positive)

Thanks a lot
Marcos
That doesn't sound good at all. I would expect a very stable, positive 5V to come from it. After all it is supposed to be a 5V regulator!
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Joined: Thu Aug 24, 2017 11:43 am

Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
The strange thing the tv works perfect! Before proceed with the mod i tested the av connection to meke sure it can sync later.
Well i have an idea, i will run the 5v source from the Vga Amp (ultimarc) i"v tested it and it generates 5v from the positive lead of the only capacitor present in the board, it has all the red,blue,green, sync and gnd, came from the vga cable, all in one.
The next thing will be enter the service menu to adjust the horizontal pos.
Will test and let you know the results!

Thank you so much for your help
Marcos
MarkOZLAD
Posts: 1004
Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
The strange thing the tv works perfect! Before proceed with the mod i tested the av connection to meke sure it can sync later.
Well i have an idea, i will run the 5v source from the Vga Amp (ultimarc) i"v tested it and it generates 5v from the positive lead of the only capacitor present in the board, it has all the red,blue,green, sync and gnd, came from the vga cable, all in one.
The next thing will be enter the service menu to adjust the horizontal pos.
Will test and let you know the results!

Thank you so much for your help
Marcos
No problem Marcos. Hope next post is about a successful RGB mod.
___________________________________________________
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
m.andrade1
Posts: 39
Joined: Thu Aug 24, 2017 11:43 am

Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Just a doubt, in my case i have that NOTUSED J281 port, that's supposed to receive a RGB external signal thru it.
Do you think will be necessary in this case to put these components on the mod, like the diagram https://m.imgur.com/xHfNHis that show the instalation directly in the chip leg.
Now because the architeture of the board that already has this J281 port do you think i can solder directly the wires on the J281 withou these components showed in the diagram.

Thanks again
Marcos
MarkOZLAD
Posts: 1004
Joined: Thu May 18, 2017 12:39 pm

Re: TV RGB mod thread

Post by MarkOZLAD »

m.andrade1 wrote:Hello Mark
Just a doubt, in my case i have that NOTUSED J281 port, that's supposed to receive a RGB external signal thru it.
Do you think will be necessary in this case to put these components on the mod, like the diagram https://m.imgur.com/xHfNHis that show the instalation directly in the chip leg.
Now because the architeture of the board that already has this J281 port do you think i can solder directly the wires on the J281 withou these components showed in the diagram.

Thanks again
Marcos
I would be attaching the red, green, blue, blanking and ground wires directly to the J281 port.

Make sure you have the red, green and blue signal wires terminated to ground with 75ohm resistors just like in the diagram. You will not need to add the capacitors because they are already on the circuit board.

Then send Composite video and audio through an AV port. Select the input.

That should be it.
___________________________________________________
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
m.andrade1
Posts: 39
Joined: Thu Aug 24, 2017 11:43 am

Re: TV RGB mod thread

Post by m.andrade1 »

Hello Mark
Perfect, will do directly into the J281 from the top and solder them from the botton as you suggest, no problem!
Now about those 75ohms resistor, give a look on the photos how i will be wiring the mod, those 6 wires will came from the Ultimarc VGA Amp, including the 5v, let me show you the picture.

https://goo.gl/photos/GQGfuVWMBLByEiYX8

Now do you think even with the VGA AMP circuit behind the mod will be necessary the 75ohms resistors ?

Thanks a lot!
Marcos
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