TV RGB mod thread

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Rftckeeper
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Re: TV RGB mod thread

Post by Rftckeeper »

Thank you for the response. I am modding a kv-20fs12. I did adjust the service menu horizontal position but It’s bottomed out at 0 and still missing a little of the left side of the picture. I saw the video of cruzlink doing the mod but it never said what he did to get it centered. The snes picture that was on the tv in the video looked completely centered with no border. My mod has a thin border on the right side and the picture is cutoff about the same amount on the left. Picture looks great but not being able to see that little bit bothers me. There isn’t any svideo on this model so I can’t grab luma. Or maybe there’s a way to? It looks like there are missing components for that port and even still I don’t believe I would be able to switch to that input. I successfully modded a 27” Sanyo which had svideo so it was a completely centered picture. I didn’t use any capacitors on that one. I tried caps and no caps on the Sony I’m trying to get centered. Is there really no way to center the picture on these tv mods if the service menu bottoms out?
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BazookaBen
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Re: TV RGB mod thread

Post by BazookaBen »

Rftckeeper wrote:. Is there really no way to center the picture on these tv mods if the service menu bottoms out?
Sometimes there is a "H cent" switch or potentiometer somewhere on the board. There might be other ways but I'm new to RGB modding.

I think another problem is that if you move the picture in one way for RGB, then composite can be thrown off. In case you have something like a NES that you haven't RGB modded
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vol.2
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Re: TV RGB mod thread

Post by vol.2 »

BazookaBen wrote:
Rftckeeper wrote:. Is there really no way to center the picture on these tv mods if the service menu bottoms out?
Sometimes there is a "H cent" switch or potentiometer somewhere on the board. There might be other ways but I'm new to RGB modding.

I think another problem is that if you move the picture in one way for RGB, then composite can be thrown off. In case you have something like a NES that you haven't RGB modded

There's typically both an H center and an H Phase shift. You have to be careful with H phase as it can cause the screen to fold over horizontally on some sets if you tweak it too far to one side.
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Rftckeeper
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Re: TV RGB mod thread

Post by Rftckeeper »

thank you for the response. i am new to rgb modding consumer TVs too but i have a couple years experience with arcade and pinball stuff. i have a nesrgb i am hooking up to the monitors and also a genesis rgb and an arcade pcb with jamma harness. I don't see any pots on the chassis. i have been reading a lot on here and it seems my issue is the sync delay? i have a great blanking signal on both a DTQ20U4SC and a KVS20FS12.
the problem I'm having is the sync. i tied into the s video luma on the daewoo still same result shifted way left. i don't have s video on the sony so i am going in through composite rca for sync on that one. i get a really nice looking centered black and white image of whatever signal i put into both tvs but as soon as i throw the blanking switch it looks good but shifts way left and cuts off the left side of the image. i think i understand this as the clamping?i read something about delaying the sync but I'm still scratching my head on that one. i tried ac coupling the rgb lines in on the sony but it just made the picture look shitty. It was still shifted left. i feel like I'm right there on both of these sets as the blanking and rgb are working flawlessly. i just can't get over the shifted picture. takes away from the mod imo. i successfully rgb modded a sanyo DS27800 and it looks great running arcade pcbs genesis and nesrgb. it had s video so i was able to use that luma to center the picture. i didn't have to use coupling caps or any inline resistors on the sanyo. it seems the rgb is default running until it sees a source so i dint even have to supply 5v to blanking. i just cut a jumper that must keep the jungle low and put a switch in line. only have to hit the switch if i want to use the inputs as they were designed to be used. i am happy that i was able to get at least one of the 3 I've done working well. i just can't seem to figure out the way to get my rgb signals to match my sync.or is it vise versa? i appreciate any knowledge or direction pointing to help me get to the point where i can understand exactly what needs to be done to remedy the horizontal shift. is it possible the coupling capacitors on the boards are too small? it seems those are .01 not .1
abispac
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Re: TV RGB mod thread

Post by abispac »

Hey guys, so im gonna buy a winnie the pooh 13inhc tv wich is a DT1350-rwpsm model and i found the eschematic here
http://www.mediafire.com/file/z5daihal6 ... M.pdf/file
I think it should be something similar to the one found here
viewtopic.php?t=60158
So if im correct The RGB is connected through pins 14-16, with pin 13 as blanking, the only thing im not sure is wich resistors should i remove so any advice would be wellcome. thanks for any help.
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abispac
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Re: TV RGB mod thread

Post by abispac »

Ok so ive been think it about it and since this is a 13 inch monitor , i dont want to screw up, so please can someone confirm what i think i need to do before i even do anything. Acording to this image
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caps 210 to 212 will stay as the are allready 100nf. After that resistors 207 to 209 should be removed and add a bridge there. next caps 17,20,23,24 im not sure what to do with those, i dont have to bother with the 1k resistors and i will feed my rgb to the c018,19,20 caps with the 75 added resistors terminated to ground? right? plus i need to find a 3.3voltage to feed the blank signal and hook that betwen resistor 206?

Am i getting this right? any help woud be truly apreciated, thanks in advance.
Another image im trying to fill to understand this a bit more, i removed the diodes as it seems i dont have any but correct me if im wrong.
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francoisadt
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Re: TV RGB mod thread

Post by francoisadt »

I do have an LG CRT which I want to hook into by linking the RGB output feed from my Pac-Man PCB dierctly
to this TV CRT.

There is a RGB switch holes which are indicated as RGB external switch. The actual RGB CIRCUIT switch IC is not installed but the lines
runs through from LEFT to RIGHT. So if I hookup the RGB lines to the OUTPUT of the RGB switch circuit block
then the R(OUT) , G(OUT) and B(OUT) will feed the jungle chip as input.

See attached diagram :

I have read previous post below and I am not understanding what is written below.
cyborc wrote:
Fallen Kell wrote:Sorry, long time lurker on this forum and I finally needed to post. I recently picked up a Sharp 27DV-S100 TV. Yes, it is a VCR/DVD combo system (and the DVD does not work), but the picture is extremely nice. After looking it over, I am trying to figure out if it is possible to RGB mod it. From everything I can find, I believe the answer is yes, but I wanted to ask someone more knowledgeable than myself to see if I am not thinking this is going to be easier than it looks.

External, everything is composite. Internally, the VCR and DVD are connected essentially through S-Video (just not using the port). However, everything is converted to RGB for the CRT. In the service manual, I found the diagram for these connections go through a single chip:


I also found the complete pin diagram for the chip:


To me that, looks like there are RGB input pins on 32-34 which are currently just going to ground (through either caps or resistors). Anyone see this chip before and know how difficult it would be to mod? I am thinking it is just a matter of wiring up an external connection to those grounded pins and and send the proper signal to tell the chip to use the RGB inputs as the source. Again, am I missing something that would make that impossible?

Here's the datasheet for that jungle IC. http://www.datasheetcatalog.com/datashe ... 76AN.shtml

You should be able to insert your RGB signal on pins 33-35 and blanking on pin 32. (0.75v) You will need to remove those capacitors to ground on the R, G and B lines and add your own capacitors in series with your external RGB signal. (0.1uf most likely) Overall, a relatively easy job. You lucked out! In my experience, Sharp CRTs look great when RGB modded.

Question:
=======
So I will do the same hack mentioned above but on pin 16, 13, 11 on the diagram block where the RGB Circuit switch called TEAC5114, suppose to be.
See red circled spaces in my attached diagrams here in this post?

Question:
=======
What is mean by "blanking on pin 32"? What is one need to do by blanking? What wire is a blank? Is that ground from the external RGb feed?

Question:
=========
What is mean by removing capacitors, adding own capacitors? Why is this needed? Do I have capasitors in my shematic on RGB flow?


MarkOZLAD wrote:
It may be possible to cut the ground plane traces but your plan is solid

I would just pump Sync and Audio through the AV port. Can solder underneath them if you want, (I generally break them out into RCA ports and run cables, but I'm weird.) If you need to trigger stereo you can by putting a cut RCA plug in the right channel. I have never soldered sync internally. Not sure why you think there needs to be a diode.

You should only need a switch for the RGB blanking. With blanking voltage disabled the RGB input won't do anything. If you will have a blanking voltage from your Scart/RGB cable you can use that to switch the RGB on, that way the TV enables RGB when you turn the console on.

Question:
=-======
To get sync from my Pac-Man PCB. Which nr on my schematic must I send/link sync to from RGB 5pin connector from Pac-Man PCB, white wire, I think it is a composite/combined sync from Pac-Man PCB?

Question:
========
How can one sent sync to AV port from white wire (sync) from Pac-man 5pin molex , balck (ground)? What is meant by "Sync and Audio through the AV port"?
Can I just combined white threaded wire and the ground and toe it together by hand and stick it into AV port or solder it to which SYNC line on my schematic
of the jungle chip?


Question:
"You should only need a switch for the RGB blanking. With blanking voltage disabled the RGB input won't do anything"
What is meant by switch here? RGB blanking? In my RGB Curcuit switch there is not chip so I just want to solder the RGB and sync on the RGB output
of RGB witch which led to the Jungle chip RGB input?

Question:
=======
On the RGB Circuot switch block diagram, there is GROUND (labelled as nr 2), and VCC (Voltage) as nr 14.
Must I wire RGB ground from Pac-man PCB to this nr 2?
Must I wire volatge from Pac-Man PCB (5 volt) red wire to nr 14?

How do I get ground from Pac-Man PCb to this chassis? Must the same power that switch on the TV (main plug 220V) feed
join somewhere the ground of the Pac-MAN PCB? into this chassis? If not will that stop any picture of showing?
So is any ground wire just ground or must the same ground feed coming RGB 5pin Pac-man PCB, also be the same
ground that feed the ground for SYNC generate the picture from jungle chip? So do I need GND from Pac-Man PCB feed
into Jungle chip somewhere?

Question:
=========
Where must I sent SYNC in (white wire) from PAc-man PCB SYNC to Jungle chip or RGB circuit switch output?
To be safe then: Please explain to me how to sent SYNC from PAc-man PCb to AV port and also wire another SYNC wire
to chassis - where on this block diagram?


I do have an LG CRT which I want to hoo ... sp=sharing

LG RGB Circuit Switch Link:
https://drive.google.com/file/d/1Wv_4N5 ... sp=sharing
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vol.2
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Re: TV RGB mod thread

Post by vol.2 »

abispac wrote:Ok so ive been think it about it and since this is a 13 inch monitor , i dont want to screw up, so please can someone confirm what i think i need to do before i even do anything. Acording to this image
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caps 210 to 212 will stay as the are allready 100nf. After that resistors 207 to 209 should be removed and add a bridge there. next caps 17,20,23,24 im not sure what to do with those, i dont have to bother with the 1k resistors and i will feed my rgb to the c018,19,20 caps with the 75 added resistors terminated to ground? right? plus i need to find a 3.3voltage to feed the blank signal and hook that betwen resistor 206?

Am i getting this right? any help woud be truly apreciated, thanks in advance.
Another image im trying to fill to understand this a bit more, i removed the diodes as it seems i dont have any but correct me if im wrong.
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This is your datasheet: https://pdf1.alldatasheet.com/datasheet ... 1238N.html

Pin 13 needs to see above 2.1VDC to turn on the Analog inputs 14,15,16. If it's any lower than that, you will get "half tone" instead. I didn't bother reading up what that does, but I think it's some kind of mixed input mode.

I guess just try with the existing 100n caps, and use 75 Ohm input resistors to ground. You will have to find a place to get the ~2.1VDC from on the inside of the set. Can't help you there.

Edit: on second glance, the datasheet also gives the analog RGB switching level as 0.7-1.0V in the "AC Characteristics" list. They say to input a signal at pin 13 and watch where it switches. You might first try starting it at 0.7VDC and ramping it up until you get blanking. Input a composite signal on the video input, and Blue on pin 16. When blue comes out of pin 20, you have the blanking level. The little chart on page 8 says it will be 2.1VDC, but then it says later on that it will be 0.7-1.0VAC Max, so I guess that's supposed to be about 2.1VDC RMS. IAC, don't make it any higher than it has to be to function correctly.
Last edited by vol.2 on Tue Mar 23, 2021 5:42 pm, edited 1 time in total.
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Rftckeeper
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Re: TV RGB mod thread

Post by Rftckeeper »

If he lifts the resistor closest to the mcu and puts 5v to that instead of the blanking pin won’t the components in line knock down to correct voltage for the jungle?
abispac
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Re: TV RGB mod thread

Post by abispac »

ok so acording to MarkOZLAD on his topic viewtopic.php?t=60158
MarkOZLAD wrote:Wow, I never finished this thread? Weird, that's not like me....

I was able to successfully mod this TV. I used the OSD Mux method to do the job. Steps are:

1) remove resistors R656, R657 and R658, these are the factory OSD RGB termination resistors
2) There are diodes on the OSD RGB circuits and there are 1000 Ohm resistors inline on the OSD RGB lines. A quick look at the OSD Mux RGB External Inline Resistor Table.jpg says that we should use 160 Ohm resistors as our new external RGB inline resistors
3) Twist one leg of a 160 Ohm resistor to a 75 Ohm resistor. Make a Y shape from the resistors. Do this three times.
4) Solder the three Y shaped Resistor pairs into the holes left by R656, R657 and R658. The leg of the 160 Ohm resistor should be on the "Jungle side", the leg of the ohm to the "Ground" side. We should have the twisted legs sticking up.
5) Solder the external R, G and B lines to the appropriate twisted legs sticking up
6) For blanking there are multiple options. Probably go with the method the 8 Bit Guy came up with, lift the leg of R635 that is closest to the Microcontroller. Install a switch. One side of the switch will go to 5V (the output leg of IC901 5V regulator), the other side of the switch will be connected by a wire to the hole left by the lifted leg of R635, the middle pin of the switch will go to the leg of R635 that we just lifted.
1) remove resistors R656, R657 and R658, these are the factory OSD RGB termination resistors

So for me it would be, remove the 2.2k resistors at r207,r208,r209 right?

2) since i dont have diodes on my skechup, i then should add 91 resistors to each 1k resistor at c018,c019,c021 and thats where i should add my RGB signal.

and
6) add 5v directly to pin 13? of course, i should add a switch before the next resistor ar r206?

Please bare with me on this one, i want to triple make sure on this one before i desolder anything as this are mostly surface mounted resistors and caps, and they are very tiny. I really would like to use this monitor for a bartop arcade, so i dont want to mess up. Thanks for any help.

Also, 5v vs 2.1vdc besides the ovius size 5 vs 2.1 , isnt the v and vdc the same? or is it a diferent type of current?

Pictures of the board im working on
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Rftckeeper
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Re: TV RGB mod thread

Post by Rftckeeper »

The way I interpreted the above post was the center post (common terminal) would connect to the lifted resistor. One position of the switch would connect to 5v so you can toggle to that to switch constant blanking and the other side would connect to the via left from the lifted resistor. That position would return the tv to stock arraignment letting the micon communicat to jungle through the resistor. I don’t believe you should be putting the 5v directly to the blanking pin on the micon. If I am wrong someone please correct me.
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vol.2
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Re: TV RGB mod thread

Post by vol.2 »

abispac wrote:ok so acording to MarkOZLAD on his topic
Mark will have to help on that, I haven't done the MUX method before, so I can't comment.
Please bare with me on this one, i want to triple make sure on this one before i desolder anything as this are mostly surface mounted resistors and caps, and they are very tiny. I really would like to use this monitor for a bartop arcade, so i dont want to mess up. Thanks for any help.
Keep in mind that, as long as there is enough room, you can just replace the surface mounted caps and resistors with through-hole versions. There's no rule that says it has to be surface mount. You just bend over the little leads into a pad and solder them down. Just be careful to buy equivalent varieties of components (ceramic, film, tantalum, electrolytic). There are instances where a different variety is okay, but don't do it unless you learn about that and you can be sure.
Also, 5v vs 2.1vdc besides the ovius size 5 vs 2.1 , isnt the v and vdc the same? or is it a diferent type of current?
I'm sorry if I confused you at all. That's not what I meant. I read the datasheet for your chip, and it strangely lists the "Analog RGB Switching Voltage" as 2.1VDC. It doesn't have a maximum for that, unless you count the value from the "Absolute Maximum Ratings" section, which says input maximums are 300mV above Vcc. So that's the value you can go up to without causing damage.

The thing that confused me is that later in the datasheet, they call out an AC value for pin 13, which is somewhere around 0.8V. I was supposing that it might be an RMS value that somehow includes a DC offset or something. I think you can safely ignore that. Certainly follow Mark's advice if he's done one of these sets before. If he says you can feed it 5VDC, then you probably can. I suppose it's just got to be above 2.1VDC to turn the input on, and you should be able to take that from Vcc. I would probe Vcc with a digital multimeter first to make sure of the voltage.
abispac
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Re: TV RGB mod thread

Post by abispac »

vol.2 wrote:
abispac wrote:ok so acording to MarkOZLAD on his topic
Mark will have to help on that, I haven't done the MUX method before, so I can't comment.
Please bare with me on this one, i want to triple make sure on this one before i desolder anything as this are mostly surface mounted resistors and caps, and they are very tiny. I really would like to use this monitor for a bartop arcade, so i dont want to mess up. Thanks for any help.
Keep in mind that, as long as there is enough room, you can just replace the surface mounted caps and resistors with through-hole versions. There's no rule that says it has to be surface mount. You just bend over the little leads into a pad and solder them down. Just be careful to buy equivalent varieties of components (ceramic, film, tantalum, electrolytic). There are instances where a different variety is okay, but don't do it unless you learn about that and you can be sure.
Also, 5v vs 2.1vdc besides the ovius size 5 vs 2.1 , isnt the v and vdc the same? or is it a diferent type of current?
I'm sorry if I confused you at all. That's not what I meant. I read the datasheet for your chip, and it strangely lists the "Analog RGB Switching Voltage" as 2.1VDC. It doesn't have a maximum for that, unless you count the value from the "Absolute Maximum Ratings" section, which says input maximums are 300mV above Vcc. So that's the value you can go up to without causing damage.

The thing that confused me is that later in the datasheet, they call out an AC value for pin 13, which is somewhere around 0.8V. I was supposing that it might be an RMS value that somehow includes a DC offset or something. I think you can safely ignore that. Certainly follow Mark's advice if he's done one of these sets before. If he says you can feed it 5VDC, then you probably can. I suppose it's just got to be above 2.1VDC to turn the input on, and you should be able to take that from Vcc. I would probe Vcc with a digital multimeter first to make sure of the voltage.
Thanks for the advice

So things are getting a bit more clear but i still have to make sure im gonna do the correct thing.

So to update , on closer inspection to the board, the board does not have the 2.2 k resistors at r206,r207,and r208, so i dont have to bother with it.
Wich i think then i only need to solder the 91omh resistors togheter with the 1k resistors at r031-r032-r033-r034 and terminate them to ground and put my rgb there right? just feed 5v to the blanking signal, hopefully later on i figure how to do it the 8th bit guy way. and that shoule be all right? Sounds to good to be true, the hardest part would be to solder the resistors on the surface without having them to peel the cooper. I think im gonna have to as a friend for some help.
Am i missing something? im sorry to ask but im the type of guy that can easy overlook things or not look at things, Pardon my bad english, as is my second lenguage.
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abispac
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Re: TV RGB mod thread

Post by abispac »

WTH? things might be easyer for me, i just discovered that my set has a scart port, i hope it works. Actually when looking for the manual for this tv, i saw that there were europw variants that had a scart outlet, but mine came with the yellow,white red outlets, so i never thought about the scart outlet, and today i took a look at the manual and saw it, so i pick the board and saw that its there fisicaly. So i might get lucky. If i get lucky what do i need to do?
Just follow instructions likr from this picture?
Image

one of the cool things is , its actualy perforated and not surface mounted, so i can actualy solder some cables...yes...

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benyamin39
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Re: TV RGB mod thread

Post by benyamin39 »

I am modding a Sanyo CRT TV manufactured in 2005, model DS 19204. I downloaded the service manual.
The jungle chip is a LA76843NMP.

I posted my work on the following thread.
viewtopic.php?f=6&t=66379

In a nutshell, To obtain a picture on the screen I had to amplify the 0-0.7V RGB signal to 0-2.4V using an op-amp (TH7315). By doing so I got the following result:
Image

My issue is that the color rendering is not good enough and the picture is saturated.
From 0 to 1.7V the picture is black and from 2.1 to 2.4V the color is saturated. (here below is a calibration image, and what I get on the screen, pay attention only to the red signal which is the only one I shifted voltage for)
Image
Image

So I want to build a voltage shifter circuit to shift the signal from 0-7Vpp to 1.7-2.1V approximately which is the voltage range of the jungle chip for which I will get the proper rendering, close to the calibration image. I don't know how to build that circuit though. I found the circuit below, but I don't know which op-amp to buy, and also if this kind of circuit will be sufficient or if a more advanced circuit is needed.

Image

Thanks in advance for your help.
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Syntax
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Re: TV RGB mod thread

Post by Syntax »

Can you add a pullup resistor to the color channels to bring the swing up?
Brad251
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Re: TV RGB mod thread

Post by Brad251 »

I have a CRT TV that can be RGB modded and wanted to know if I could just wire everything to a VGA port instead of a scart port without the need for any additional components like potentiometers, etc. My plan is to connect my PC to my CRT TV directly via VGA and CRT emudriver. I just don't know if there would be any sync issues?
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vol.2
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Re: TV RGB mod thread

Post by vol.2 »

Brad251 wrote:I have a CRT TV that can be RGB modded and wanted to know if I could just wire everything to a VGA port instead of a scart port without the need for any additional components like potentiometers, etc. My plan is to connect my PC to my CRT TV directly via VGA and CRT emudriver. I just don't know if there would be any sync issues?
The physical connector is irrelevant. Your problem is that the PC is going to output H and V sync separately. You will need a device to combine sync like an extron unit or you will need to build a circuit to combine the sync.
benyamin39
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Re: TV RGB mod thread

Post by benyamin39 »

Syntax wrote:Can you add a pullup resistor to the color channels to bring the swing up?
Thx for the suggestion. I don't know how exactly a pull-up resistor configuration works. I guess I need to work from the 5v supply to swing up the voltage with a resistor and maybe add-on with rgb signal. Looking at the documentation on the web, often a pull up resistor is associated with a transistor. What is the general arrangement of a pull up resistor in this case? Thx for ur help
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dmauro
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Re: TV RGB mod thread

Post by dmauro »

I'm looking to do an RGB mod on a Sony KV-27V42 using 15-pin VGA input. This is an exceptionally long thread, but I think I've read enough of it to have a pretty decent handle on what I should be doing, but I still have some questions I'm hoping someone(s) can help with:

So looking at this diagram from MarkOZLAD and comparing to the service manual for the 27V42, it looks like those values are all correct (this TV has the 5.6K resistors in the OSD RGB and no diodes), so I think the RGB aspect looks like it should be relatively straight-forward, but the blanking and sync are more interesting:

* If I'm using 15-pin VGA, they have H/V sync, but I need to get that into a composite sync. I've read a little about that and it seems like maybe I could just mix those two (?) but that might be dangerous for whoever is sending the signal. I've seen some more complex solutions, but obviously would like to keep things simple, so I'm curious what others have done (I'm assuming I'm not the only one not doing a SCART port).
* Not using SCART also means I don't have a 5v line, but maybe I do...? It seems like pin 9 sometimes/often(?) carries 5v? Should I just go through and test a whole bunch of devices to see if they send that, or would it be safer to just pull the 5V from the TV and add a toggle switch to the back? Obviously not having to toggle on/off would be nice, but I'd be a little worried that maybe some devices would send 5v and some may not.
* And then just a soldering question: I imagine the .01uF capacitors in the the OSD RGB that need to be replaced are the very tiny ones. Are those the sorts of things I could hope to remove with just a standard soldering iron and soldering braid, or will I need some better equipment?

Also just wanted to give huge props to everyone that's done all of the work testing things and sharing in this thread. It's really cool that I can potentially do a relatively simple mod to add game-changing functionality to this Trinitron thanks to y'all.
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maxtherabbit
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Re: TV RGB mod thread

Post by maxtherabbit »

My advice to you would be to connect only pin 13 (h-sync) to the TV (via a 470R to drop it down to video level) and handle sync combination externally if needed using an Extron RGB 192V or similar. All my VGA dongles output C-sync on pin 13 as do many other devices targeted at 15kHz content.

Regarding blanking, I would connect pin 9 but also add a switch for manual override in the event your source doesn't provide it
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Re: TV RGB mod thread

Post by francoisadt »

Hi Can anyone please be so kind and answer some of my questions above. Look at post dated 23March2021 11:39am, but firim mod approval put it later in the list, day after. I wantto fix my pacman cabinet this weekend. strart oractising for a pperfect pacman..
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dmauro
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Re: TV RGB mod thread

Post by dmauro »

maxtherabbit wrote:My advice to you would be to connect only pin 13 (h-sync) to the TV (via a 470R to drop it down to video level) and handle sync combination externally if needed using an Extron RGB 192V or similar. All my VGA dongles output C-sync on pin 13 as do many other devices targeted at 15kHz content.

Regarding blanking, I would connect pin 9 but also add a switch for manual override in the event your source doesn't provide it
Oh interesting, perhaps then I'll look into what most of my devices are actually outputting for sync. I don't know for sure they're do H/V sync, I just kind of figured they would for VGA pinout. And yeah, just doing both for blanking is probably the right idea. A little more work, but better than having to go back in later and do it if it winds up being a problem. Thank you! :D
abispac
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Re: TV RGB mod thread

Post by abispac »

Thanks for reading, so english is my second lenguage, and i think im mixing methods or dont fully understand them and therefore i mix methods myself. So from now on i want to do as many rgb mods as i can ,and mostly for arcade related projects. Im not very good at soldering things so so far 4 out of 5 tvs ive tried the rgb mod, have failed, but ill kep trying until i fully understand what the diferences are.
So ive been told that the osd mux mix method is by far the best option, now, i think this is where i got it wrong, does the osd mux method uses a switch as the 8t bit guys did on hes rgb mod? or that is just a regular rgb mod? can someone explain to me what the diferences are so i can avoid mixing methods, thanks in advance.
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Osirus
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Re: TV RGB mod thread

Post by Osirus »

vol.2 wrote:
Brad251 wrote:I have a CRT TV that can be RGB modded and wanted to know if I could just wire everything to a VGA port instead of a scart port without the need for any additional components like potentiometers, etc. My plan is to connect my PC to my CRT TV directly via VGA and CRT emudriver. I just don't know if there would be any sync issues?
The physical connector is irrelevant. Your problem is that the PC is going to output H and V sync separately. You will need a device to combine sync like an extron unit or you will need to build a circuit to combine the sync.
CRT Emudriver has support for Composite Sync.

https://www.youtube.com/watch?v=3YsCj55ZM1Y

Using this yes, you can do a mod with a "VGA" (actually DE-15) port on the TV and use a VGA cable to connect to a CRT Emudriver enabled PC. Use pin 13 for Sync.
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vol.2
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Re: TV RGB mod thread

Post by vol.2 »

Osirus wrote:[
CRT Emudriver has support for Composite Sync.
huh. crazy.

Still though, it's a real pain in the ass to setup.
abispac
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Re: TV RGB mod thread

Post by abispac »

So after failing at the winnie the poo tv mod, today i got me another donor tv, a 13 inch Emerson-EWC-1304 , i scraped the vcr part and after findnd the manual here:
https://diagramas.diagramasde.com/otros ... TV-VCR.pdf i think im getting the hang of it, im starting to trace rgb lines froms the osd to the end of the neck. I just got a quick question before i think on how should i inject my rgb signal.

How do i know if this is a digital only rgb signal osd?
I ask because looking for the manual, lead me to a similar post on onother place but the model was diferent, it was a 19" set, and the guy was told his rgb signals were digital.

Now if you look at my image, i think i have traced the path and found the place where i should tap my signal if im not mistaken and of course if is not a digital rgb osd
Spoiler
Image
Thanks for your help.
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maxtherabbit
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Re: TV RGB mod thread

Post by maxtherabbit »

abispac wrote:Thanks for reading, so english is my second lenguage, and i think im mixing methods or dont fully understand them and therefore i mix methods myself. So from now on i want to do as many rgb mods as i can ,and mostly for arcade related projects. Im not very good at soldering things so so far 4 out of 5 tvs ive tried the rgb mod, have failed, but ill kep trying until i fully understand what the diferences are.
So ive been told that the osd mux mix method is by far the best option, now, i think this is where i got it wrong, does the osd mux method uses a switch as the 8t bit guys did on hes rgb mod? or that is just a regular rgb mod? can someone explain to me what the diferences are so i can avoid mixing methods, thanks in advance.
I don't mean to be a dick, but maybe you should study up on some electronics fundamentals first instead of just blindly tinkering and failing while potentially damaging TV chassis. All the information is out there in the RGB mod thread if you can read it and digest it
mgerety
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Re: TV RGB mod thread

Post by mgerety »

I'm just finished modding a Toshiba 32A33 and I'm having an issue. I'm getting blue only through the VGA cable.

I've Quadruple checked continuity between on RGB from the VGA connector to my small project board where I tie R, G, and B to ground via 75ohm resistors, and push each through a 104 cap to the other side of the board. I'm certain of good continuity between the VGA and the "in" side of this board, and continuity between the "out"side the the wires soldered to the jungle. I've ensured the wires are making good contact with the jungle pins (I soldered the wires to the legs topside) by checking continuity between the outer edge of the wire and the pins below the board. there are no shorts, I obsessively checked.

I used a 22k and 33k resistor as a voltage divider from the 5V source suggested by bratworst/others to get a 3V signal to kick the jungle into RGB mode.

Through the VGA/Scart connection I get this:

Image

Flip the switch to put the jungle back in YUV mode and pump the 15khz vga through a vga-component transcoder, and get this through component:

Image.


Also, there's a dramatic shift left. i put sync through the green Y (well, it's yellow on this set but whatever, it's the green wire). Suggestions on resolving this?

Thanks in advance.


Any suggestions? Bad voltage on the blanking pin? Anything else? I'm at a loss at the moment.
abispac
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Re: TV RGB mod thread

Post by abispac »

maxtherabbit wrote:
abispac wrote:Thanks for reading, so english is my second lenguage, and i think im mixing methods or dont fully understand them and therefore i mix methods myself. So from now on i want to do as many rgb mods as i can ,and mostly for arcade related projects. Im not very good at soldering things so so far 4 out of 5 tvs ive tried the rgb mod, have failed, but ill kep trying until i fully understand what the diferences are.
So ive been told that the osd mux mix method is by far the best option, now, i think this is where i got it wrong, does the osd mux method uses a switch as the 8t bit guys did on hes rgb mod? or that is just a regular rgb mod? can someone explain to me what the diferences are so i can avoid mixing methods, thanks in advance.
I don't mean to be a dick, but maybe you should study up on some electronics fundamentals first instead of just blindly tinkering and failing while potentially damaging TV chassis. All the information is out there in the RGB mod thread if you can read it and digest it
Or instead of criticizing what can be a simple problem of a lenguage translation problem, you could just have explained the basics, like "o the mix method is diferent than the original rgb method because of this" .I read alot on this pages ,and whatch videos, i understan the guides, and get confused, as some guys use a switch and some dont, but both methods look similar. A switch does not bother me in fact. But its kind of confusing. At the first page of this particular topic, where mikejmoffit explains
Spoiler
* Snip-snap the internal OSD RGB signals going into the jungle mixer
* Inject your RGB there instead, with 75 ohm resistors to ground and then a ~0.1uF capacitor in series to the RGB input
* Pull the jungle mixer blanking pin out of circuit, and tie it high (nearby jungle VCC, usually 3.3~5V) to make it always blanking (always showing RGB)
* Put your composite sync signal into an available luma input (or composite if that's all you have)
* Put that noise on a switch so you can change it back and forth
* Enjoy RGB
My guess this is just the regular rgb mod.
I have not found the mix method eplained, perhaps someone should adde it at the first page so i does not gets confused, i think is where instead of lifting the legs of the chip,you used resistors to be able to use the osd with the rgb together?

Dont get me wrong maxtherabbit. I dont mean to be an ass, but people can learn more if you guys are willing to help.I do know some electronics fundamentals, i can follow diagrams, i can trace them, i know the diferences betwen resistors,capacitor,filters,diodes, and more, is just sometimes things get lost in translation. To be honest i do wish i knew where do you guys get the values that need to be added for resistors, once you find where to tap the signal. But thanks to Markcozlad theres info on his signature that helps. I wish i can succesfully mod every single monitor i get but hey, you have to brake eggs to make an omellete.
let me pu it this way, if you help only those that understand something and not helping those that dont understand something, then you are not helping.
Chears bro.

PS: Im still wondering how do you guys know if a chip is digital rgb or analog?
viewtopic.php?p=1447875#p1447875
Last edited by abispac on Sat Mar 27, 2021 6:35 pm, edited 1 time in total.
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