TV RGB mod thread

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fandangos
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Re: TV RGB mod thread

Post by fandangos »

Dochartaigh wrote:This has probably already been asked and answered, but I was wondering for TV's which have component input, is there much of a difference in picture quality between RGB modding that TV, and using the stock component inputs?

I wonder because when I switch between RGB SCART cables on my PS2 (think I tried this same comparison on my original Xbox at one point too), and the regular PS2 component cables (even on high-end BVM and PVM's), they honestly seem to be like 98% identical to each other (and that other 2% could just be wishful thinking).
This site have the comparison you are looking for:
http://retrorgb.com/rgbmonitors.html

Also, one thing I noticed, every crt tv with component input they have some artifacts to reduce scanlines. Much like the Sony Trinoton they are like a diamond shaped pixel, it's hard to explain but even some shaders try to mimic this.
Old crts without component, don't have this and have way less complex comb filters, which to me means a way more pure image if you RGB hack it. Closer to the PVM/BVM.
Dochartaigh
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Re: TV RGB mod thread

Post by Dochartaigh »

leonk wrote:On consumer CRT TV's, not that much. But then again, not all consoles output component! Especially the older ones ..
I'm actually getting a Shinybow RGBs (SCART) to YPbPr converter when it's back in stock so I can run all my systems (even NES/SNES/Genesis/etc) through my Extron Crosspoint to my consumer TV's (which ALL have component inputs - even the little Sony 13"), so I was wondering if there was much of a benefit to RGB modding them (at least my Sony FV310 at least).


fandangos wrote: Also, one thing I noticed, every crt tv with component input they have some artifacts to reduce scanlines. Much like the Sony Trinoton they are like a diamond shaped pixel, it's hard to explain but even some shaders try to mimic this.
Old crts without component, don't have this and have way less complex comb filters, which to me means a way more pure image if you RGB hack it. Closer to the PVM/BVM.
Gotcha, so if I'm even thinking about RGB modding a modern (well, as modern as CRT's get) it's probably not even worth it then.
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mikejmoffitt
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Re: TV RGB mod thread

Post by mikejmoffitt »

fandangos wrote:Also, one thing I noticed, every crt tv with component input they have some artifacts to reduce scanlines. Much like the Sony Trinoton they are like a diamond shaped pixel, it's hard to explain but even some shaders try to mimic this.
Old crts without component, don't have this and have way less complex comb filters, which to me means a way more pure image if you RGB hack it. Closer to the PVM/BVM.
Nope. FD Trinitrons might have different characteristics regarding focus, convergence, and general beam shape, but it's nothing like this. Putting contrast at max will make the gaps between scanlines lower, but it's nothing complicated like you are inferring.

"CRTs with component" aren't some magical class of television and making claims surrounding that distinction is just misleading.
Image
szucconi
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Re: TV RGB mod thread

Post by szucconi »

KnuckleheadFlow wrote:tjsynkral, dude! You were so right. There was tons of wasted space.
I decided to throw out my ideas of how it should be spaced out and wanted to see how close I can make everything without any other considerations. About halfway through I realized it won't be that much harder to hand solder and that I like this layout way better. The board is now 42.5mm * 25mm, 1 2/3" * 1". That's less than 40% of the original area!

Image

Image
Do you have any notion of selling these or allowing distribution either populated or not? I've got a basement full of TVs that I'd like to do this to in some form and this is much cleaner then my own solution. Even boards with just the LT1675 would save me tons of trouble.
fandangos
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Re: TV RGB mod thread

Post by fandangos »

mikejmoffitt wrote:
Nope. FD Trinitrons might have different characteristics regarding focus, convergence, and general beam shape, but it's nothing like this. Putting contrast at max will make the gaps between scanlines lower, but it's nothing complicated like you are inferring.

"CRTs with component" aren't some magical class of television and making claims surrounding that distinction is just misleading.
I had sony trinitrons, the 34 inches SD model and I have now a Sony PVM 2950Q and a few 20 inches BVM here.

I might not have the techinical knowledge to point what exactly causes this but CRT later in life used some scanline reduction filters. This makes total sense since most consumers would buy a TV for movies and watching TV (sports), those kind of presentation don't need scanlines.
I know 480i wouldn't produce scanlines as 240p. But still The Sony Trinitrons have the most complex pcbs I've ever seen on a CRT.
If you take a close look you can see that diamond shapped effect that I have no more means to describe as that.

When using a PVM or BVM this effect is gone, you see only square pixels and the scanlines between them.

Found a picture to prove my point
Image

I know this is S-Video vs RGB but this effect is noticeable with YPbPr to RGB convertion.
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mikejmoffitt
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Re: TV RGB mod thread

Post by mikejmoffitt »

fandangos wrote: I might not have the techinical knowledge to point what exactly causes this but CRT later in life used some scanline reduction filters.
This is why I'm trying to tell you that this isn't what you're seeing. There's no such filter. As the beam gets brighter it is going to lose focus on consumer-grade sets. What you're seeing is a result of the display being older and cheaper. There is nothing fancy going on here.
Image
Dochartaigh
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Re: TV RGB mod thread

Post by Dochartaigh »

I saw the nice tutorial on RGB modding a JVC TM-H1950CG (instead of buying the impossible to find IF-C01COMG RGB input card) - which I want to try on my TM-H150CG (though I've never done anything like that before).

...but what about the JVC TM-H1700G (and H1900G) series which doesn't have the input card slot? Has anyone tried RGB modding one of those? Would the process be similar? The most I've done electronics wise is built my own sync stripper (from a DIY kit) and installed it in a SCART head...

These 750+ TVL monitors are really stunning on S-Video (comparing it to a bunch of PVM's and BVM's and it's very surprising for only using S-Video). And I recently picked up a couple of them so if I brick it I won't be too mad...(just a bit sad lol), but I would most definitely need some direction as I have no clue what I'm doing...
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buttersoft
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Re: TV RGB mod thread

Post by buttersoft »

fandangos wrote:Could someone elaborate on this: " 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)"

My tv has a TB1230N, with analog RGB pins.
Schematics here:
http://html.alldatasheet.com/html-pdf/3 ... 230AN.html

I'm not sure which pin is the fast blank and how to wire it? I need to feed voltage to it, is that correct?
Pin 21 is the blanking, feed it ~3V-5V. Pin 22 *should* be taken care of by the sets TV/AV switch. Nothing is set in stone though.
viletim
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Re: TV RGB mod thread

Post by viletim »

mikejmoffitt wrote:
fandangos wrote: I might not have the techinical knowledge to point what exactly causes this but CRT later in life used some scanline reduction filters.
This is why I'm trying to tell you that this isn't what you're seeing. There's no such filter. As the beam gets brighter it is going to lose focus on consumer-grade sets. What you're seeing is a result of the display being older and cheaper. There is nothing fancy going on here.
Yes, it's mostly the differences in picture tube technology -- in the shadow mask/cathode gun arrangement. The picture tubes of pro monitors were much more expensive than what was made for equivalent size consumer TV sets.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

MarkOZLAD wrote:Hey all,

Have started a new thread here on a mod

http://shmups.system11.org/viewtopic.php?f=6&t=60130

Would be great if some experienced guys could have a look at it and provide some advice.

Cheers,

MarkOZLAD

I successfully completed the mod this week. I have written up the results in the main thread. In the end I found that modding this TV was very straightforward, with help from forum members and the result (when my TV isn't having convergence issues) is quite amazing. The RGB picture quality is light years ahead of the composite video on these Trinitron sets.

Just a shame the TV has horizontal convergence issues. Probably why it was left on the side of the road in the first place. Has anyone here had experience fixing them?

Image
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viletim
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Re: TV RGB mod thread

Post by viletim »

MarkOZLAD wrote:
I successfully completed the mod this week. I have written up the results in the main thread. In the end I found that modding this TV was very straightforward, with help from forum members and the result (when my TV isn't having convergence issues) is quite amazing. The RGB picture quality is light years ahead of the composite video on these Trinitron sets.

Just a shame the TV has horizontal convergence issues. Probably why it was left on the side of the road in the first place. Has anyone here had experience fixing them?
Is it like this uniform across the screen. If so could be an electrical adjustment called H-Stat. Horizontal electro-static convergence. It's a usually a potentiometer on a tap from the high voltage winding on the transformer. It may have failed open circuit in your case as it looks way out.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

viletim wrote:
MarkOZLAD wrote:
I successfully completed the mod this week. I have written up the results in the main thread. In the end I found that modding this TV was very straightforward, with help from forum members and the result (when my TV isn't having convergence issues) is quite amazing. The RGB picture quality is light years ahead of the composite video on these Trinitron sets.

Just a shame the TV has horizontal convergence issues. Probably why it was left on the side of the road in the first place. Has anyone here had experience fixing them?
Is it like this uniform across the screen. If so could be an electrical adjustment called H-Stat. Horizontal electro-static convergence. It's a usually a potentiometer on a tap from the high voltage winding on the transformer. It may have failed open circuit in your case as it looks way out.
Thanks for getting back to me viletim.

The issue is uniform across the screen. I found in the service manual where it says to adjust the h.stat potentiometer so I put a dot pattern on the screen and tried adjusting it. It did affect the picture but I was unable to get it to converge. The service manual also mentioned that if it didn't work to use the the H.Stat in conjunction with the V.Stat magnet but I still wasn't able to make an impression.

It seems like the set has a circuit that auto calibrates this on startup but that is failing. Sometimes it works for a period of time.
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Star1
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Re: TV RGB mod thread

Post by Star1 »

Dochartaigh wrote:I saw the nice tutorial on RGB modding a JVC TM-H1950CG (instead of buying the impossible to find IF-C01COMG RGB input card) - which I want to try on my TM-H150CG (though I've never done anything like that before).

...but what about the JVC TM-H1700G (and H1900G) series which doesn't have the input card slot? Has anyone tried RGB modding one of those? Would the process be similar? The most I've done electronics wise is built my own sync stripper (from a DIY kit) and installed it in a SCART head...
Glad you like the guide :)
As for the 1700 and 1900, I have not seen any in person, or their service manuals, but I'd be willing to bet they use the same jungle ic. However, modding would be more like a "normal" rgb mod since you would need to blank the inputs (the 150, 1750 and 1950 does this out of the box), and perhaps more importantly, since they lack a card slot, you would have to cut open the chassis to make an input.
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buttersoft
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Re: TV RGB mod thread

Post by buttersoft »

viletim wrote: Is it like this uniform across the screen. If so could be an electrical adjustment called H-Stat. Horizontal electro-static convergence. It's a usually a potentiometer on a tap from the high voltage winding on the transformer. It may have failed open circuit in your case as it looks way out.
Might depend on the model? From what I've seen, the feedback lines for the overvoltage protection come from the h.stat too. If they aren't getting the right levels, the set won't turn on. So it probably hasn't failed open? That's a guess because I'm not sure about this model, i must admit. Can't even see the H.stat on the schematics, though i haven't combed them. Assuming for the moment that I'm guessing right...

For other sets Sony often used to show the resistors inside the resin block on the schematics, but not their values. So they also showed the feedback lines. You can fool those, of course, but then you might not have protection on the high-voltage. The H.stat's, from what i've been able to learn, often came broken as spares, and they've always been a pain. They certainly weren't meant to last this long. There's a few threads on here if you search for the term PVM-2550Q.

Run the set in the dark and see if there's any corona, mb? Or is there visible jitter on the horizontal convergence already, MarkOZLAD?

EDIT: I guess it's possible for the H.Stat to fail and the feedback lines still work, if it is set up that way, but it'd have to be failure at one of the HV connection points, just about. Does that sound right, Tim?
Dochartaigh
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Re: TV RGB mod thread

Post by Dochartaigh »

Star1 wrote:Glad you like the guide :)
As for the 1700 and 1900, I have not seen any in person, or their service manuals, but I'd be willing to bet they use the same jungle ic. However, modding would be more like a "normal" rgb mod since you would need to blank the inputs (the 150, 1750 and 1950 does this out of the box), and perhaps more importantly, since they lack a card slot, you would have to cut open the chassis to make an input.
Did you make that guide? Think I just PM'd you on CRT Gaming reddit (and thanks again!). I'm going to start with modding the TM-H150CG and see how I do on that one first (my biggest concerns now is buying the 100% correct capacitors and resistors and breadboard and such -there's SO many on sites like DigiKey it's a bit overwhelming-, and mounting some BNC connectors cleanly on the back - may drill into the blank plate that's there now for that and find some surface mount BNC's to attach to it).

If it's a success I can buy (hopefully) the Service Manual for the TM-H1700G, along with taking close-up shots of the main chip to post online for into. Is this forum (and this topic) the best place to post my photos of this project, or make a new topic about this specific mod? Is there another forum where this stuff is talked about in more detail? If I start on this project I'm going to need some major hand-holding in an endeavor like this...like I don't even know how to use the multimeter I own...(but am otherwise decently handy with soldering and can follow diagrams like the breadboard workup for the H150CG to make my own).
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Star1
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Re: TV RGB mod thread

Post by Star1 »

Dochartaigh wrote:
Star1 wrote:Glad you like the guide :)
As for the 1700 and 1900, I have not seen any in person, or their service manuals, but I'd be willing to bet they use the same jungle ic. However, modding would be more like a "normal" rgb mod since you would need to blank the inputs (the 150, 1750 and 1950 does this out of the box), and perhaps more importantly, since they lack a card slot, you would have to cut open the chassis to make an input.
Did you make that guide? Think I just PM'd you on CRT Gaming reddit (and thanks again!). I'm going to start with modding the TM-H150CG and see how I do on that one first (my biggest concerns now is buying the 100% correct capacitors and resistors and breadboard and such -there's SO many on sites like DigiKey it's a bit overwhelming-, and mounting some BNC connectors cleanly on the back - may drill into the blank plate that's there now for that and find some surface mount BNC's to attach to it).

If it's a success I can buy (hopefully) the Service Manual for the TM-H1700G, along with taking close-up shots of the main chip to post online for into. Is this forum (and this topic) the best place to post my photos of this project, or make a new topic about this specific mod? Is there another forum where this stuff is talked about in more detail? If I start on this project I'm going to need some major hand-holding in an endeavor like this...like I don't even know how to use the multimeter I own...(but am otherwise decently handy with soldering and can follow diagrams like the breadboard workup for the H150CG to make my own).
Yep, that's me. I like the idea of mounting BNC's into the plate, I have though about it myself, but haven't gotten around to it. Just ask if there's anything. I'll try to reply as best I can, and there are far more knowledgeable dudes than me browsing this thread from time to time. I'd be curious to see just how similar the H1700 is.
Dochartaigh
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Re: TV RGB mod thread

Post by Dochartaigh »

Star1 wrote: Yep, that's me. I like the idea of mounting BNC's into the plate, I have though about it myself, but haven't gotten around to it. Just ask if there's anything. I'll try to reply as best I can, and there are far more knowledgeable dudes than me browsing this thread from time to time. I'd be curious to see just how similar the H1700 is.
I'm totally prepared to open it up and take high-def macro shots and all - and document the process (if it works of course ;) First step, which would help alot, is getting the service manual, right? So if anybody has the service manual for the JVC TM-H1700G, PLEASE let me know (I'll post around and see if anybody else has it too).
Ryoandr
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Re: TV RGB mod thread

Post by Ryoandr »

Greetings all.
This is gonna be a little wall-of-text-y, so bear with me.
I found this topic talking about modding JVC monitors, I happen to have 3 JVCs, a TM-H1900 a TM-H1950 and a DT-V1710 (I also had a TM-H1750 that I gave to a friend, I'll probably mod it too).
I was lucky enough to get an IF-C01COMG RGB card with one of the monitors.
While I comtempled the idea of modding the 1750/1950s, I asked myself if recreating the RGB card was possible as it also allows component input and RGBHV (useful for DT-V and panasonic BT-Hs also). So I opened the card and I was shocked at how simple the thing is. It's a bunch of passives, transistors, some pots and a regulator. Circuit trace is pretty much one side. And the connector is just an IDE like 50 pin socket.
However I don't have the knowledge nor the tools to do such recreation. So I was wondering if I could help someone qualifed enough to do so, by taking pics, measurements and so.

As for the 1*00 models, the schematics can actually be found, and they show that they use the same TDA1276AN but all RGB related components are missing, so it should be very possible to do a similar mod to enable RGB input.

So, at this point, help me figuring it out :) I really want to contribute in some way as those JVCs are pretty damn amazing.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Have started a new thread for my latest RGB mod attempt.

http://shmups.system11.org/viewtopic.php?f=6&t=60158

This is for a TEAC CT-M5122H, the same model that @buttersoft had issues with.

Would greatly appreciate any feedback/suggestions with how to do this mod.

Cheers,

MarkOZLAD
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adcurtin
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Re: TV RGB mod thread

Post by adcurtin »

KnuckleheadFlow wrote:tjsynkral, dude! You were so right. There was tons of wasted space.
I decided to throw out my ideas of how it should be spaced out and wanted to see how close I can make everything without any other considerations. About halfway through I realized it won't be that much harder to hand solder and that I like this layout way better. The board is now 42.5mm * 25mm, 1 2/3" * 1". That's less than 40% of the original area!

Image

Image
Can you share your PCB files and / or a parts list?

I'm about to do this RGB mod to my tv, and not only is your method better than a 4PDT, I also think it will be easier overall.
Ryoandr
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Re: TV RGB mod thread

Post by Ryoandr »

So, let's see the insides of an IF-C01COMG

Image

Image

You can see that it only uses very basic components. But the worst is 90% of the components are unused (at least 1 transistor and 1 resistor for each line, and probably more). I checked traces and I came up with the circuits.

Image

Transistors are C3311
The regulator is a BA12T.
The connector is a 50 pin, DIN 41612 style (ie Hirose PCN10A 50P, EA version also fine. WARNING, not the Omron XC5A-5022). Although 50 pin isn't actually part of the standard, it is offered by many manufacturers.

The board is around 178mmx129mm.

Anyone efficient enough with CAD software ? Everything can be through hole, and there's a lot of space. One thing that could be done is put some pin headers for the inputs, so each person could adapt the connectors they want/need on the backplate, like BNCs, phonos, HD15, a SCART Socket...
Last edited by Ryoandr on Mon Jun 19, 2017 4:10 pm, edited 1 time in total.
frsj8112
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Re: TV RGB mod thread

Post by frsj8112 »

Ryoandr wrote:So, let's see the insides of an IF-C01COMG

Image

Image

You can see that it only uses very basic components. But the worst is 90% of the components are unused (at least 1 transistor and 1 resistor for each line, and probably more). I checked traces and I came up with the circuits.

Image

Transistors are C3311
The regulator is a BA12T.
The connector is a 50 pin, DIN 41612 style (ie Omron XC5A-5022). Although 50 pin isn't actually part of the standard, it is offered by many manufacturers.

The board is around 178mmx129mm.

Anyone efficient enough with CAD software ? Everything can be through hole, and there's a lot of space. One thing that could be done is put some pin headers for the inputs, so each person could adapt the connectors they want/need on the backplate, like BNCs, phonos, HD15, a SCART Socket...

Awesome job man!!! :mrgreen:
hunkmuffin
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Re: TV RGB mod thread

Post by hunkmuffin »

Hi I have tried my first RGB mod on a Sony KV-32V68. I am wondering if I terminated my grounds correctly. I used 75ohm resitors to ground off the R,G,B, and sync line respectively. I read somewhere that all the grounds on the panel mount SCART connector are sharing the common ground. So, I hooked all of them together and connected the ground to the s-video input because it would not trigger unless the grounds were connected to it. It automatically deferred to composite video when no ground is present, and I wanted my sync to go to s-video instead. I hooked up everything to a 4PDT switch with 5V on one side to activate RGB. Everything woks, but I am getting some interference. Also there is a faint vertical bowing line running down the left side of a screen that I can't figure out. Is it the voltage, or is it grounded wrong?

Thanks for the help

Image
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Star1
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Re: TV RGB mod thread

Post by Star1 »

Hi, I'm the one who made the rgb mod guide for jvc pro sets. I also played with the idea of cloning the input card, but decided not to bother since modding would be so easy. I could definitely see myself wanting to make one if I ever get my hands on a DT-V.

I do have a list of all the components needed (taken from the actual service manual of the card) can send it later if you want. Compnents would be very cheap, assuming similar-ish transistors aren't costly (I tried finding the originals, it looks like they are out of production).
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Star1
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Re: TV RGB mod thread

Post by Star1 »

http://imgur.com/a/B44Jb

Here is the schematic for the IF-CO1COMG

http://imgur.com/a/oefRk

Parts list

Legend:
MF-R: metal film resistor
CR: Carbon resistor
E cap: electrolytic cap
C cap: Ceramic cap
MF cap: metalized film cap
Ryoandr
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Re: TV RGB mod thread

Post by Ryoandr »

Nice. Thanks.
While 1/1 cloning might not be worth it due to PCB size, I have some ideas to replicate the card.
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Star1
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Re: TV RGB mod thread

Post by Star1 »

I suppose a solution with two pcb's, with some kind of ribbon cable in between would be very feasible.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

Please remove my LG Rgb Scart mod from the top post please. It has been discovered that it was showing Composite video via Scart. (I feel dirty just saying it!)

Currently investigating options, focussing on the EEPROM.
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berq
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Re: TV RGB mod thread

Post by berq »

I'm stuck.
Here are what my various video signals look like. The problem is that the image is too dark. It's not a brightness or flyback G2 adjustment problem, as turning them up doesn't make the "missing" colors start to appear; the information simply isn't there. To my untrained eye, it looks like my chassis (Zenith GX) doesn't process signals below a certain voltage. If the darker colors are lower voltages, that might explain why those colors aren't present on screen - just my guess. The part I'm stuck on: how do I make the MVS signal conform to the proper voltage range?

(image links to larger version)
Image
lukilla
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Re: TV RGB mod thread

Post by lukilla »

berq wrote:... The part I'm stuck on: how do I make the MVS signal conform to the proper voltage range?

...
You need to adjust the amplitude and gain in your video amplifier, that chip I think wont cut it because is rated for 1v video input. If you don´t have rgb in the jungle IC and need to use the crt board you can build one of Tim´s amps:

http://members.optusnet.com.au/eviltim/ ... ga2arc.htm
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