TV RGB mod thread

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me@danieldoyle.com
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Re: TV RGB mod thread

Post by me@danieldoyle.com »

MarkOZLAD wrote:> Hi me, its me, you just switched your soldering from SVideo to using Composite for the sync and it worked!

It's possible you just needed to plug an s-video cable into the port to trigger the "sense" line on the s-video.

Mod looks great.
The man himself! Thanks so much for all your contributions on this thread and creating a method to do this without losing OSD. Just reading through your posts is very educational. I bet you're right on the svideo thing, it didn't shift left too much so maybe I'll skip moving it back for now since I don't see a specific need. Honestly I'll probably never use another input on this set again anyway
RileySkye100
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Re: TV RGB mod thread

Post by RileySkye100 »

So I'm about ready to get started into modding some CRT TVs I have with RGB. However, I'll start small which will be this Orion TV1329. I have a link to the service manual here: https://www.manualslib.com/manual/70007 ... v1329.html
If it doesn't show up, you can always Google it. So I really need to know what specific components to get for this model and how I would go about doing it. I already have the SCART sockets I ordered from Console5 a while ago here: https://console5.com/store/female-scart ... e-180.html

Any help and suggestions I can receive here would be really great and if successful with this one, I'll do more mods in the future and refer here for any help. Thank you.
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DotMatrixMoe
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Re: TV RGB mod thread

Post by DotMatrixMoe »

RileySkye100 wrote:So I'm about ready to get started into modding some CRT TVs I have with RGB. However, I'll start small which will be this Orion TV1329. I have a link to the service manual here: https://www.manualslib.com/manual/70007 ... v1329.html
If it doesn't show up, you can always Google it. So I really need to know what specific components to get for this model and how I would go about doing it. I already have the SCART sockets I ordered from Console5 a while ago here: https://console5.com/store/female-scart ... e-180.html

Any help and suggestions I can receive here would be really great and if successful with this one, I'll do more mods in the future and refer here for any help. Thank you.
I'd get a pair of m3 screws and a pair of m3 nuts. (3mm drill bit) I'd get a SPDT switch, or if you want to be flashy like I did on my trinitron, a guitar foot switch.

Where to obtain them? You can easily find the m3 machine screws and nuts in Walmart or Home Depot. For the switch, lovemyswitches.com make high quality switches, but eBay has cheaper shipping. (Oh, and if you go this route, get a 12mm drill bit)

Edit: Pins (in the exact order of R, G, and B) are 12, 13, 14 of the jungle chip divided by 4.7k resistors in R646, R647, and R648. Blanking is located in pin 15 of the Jungle IC. Using this information, you can follow Mark OZLAD's mux instructions.
(I can't help but to think it's digital however, due to the lack of capacitors present. This set may be unmoddable.)
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culvos
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Re: TV RGB mod thread

Post by culvos »

Hi, I'm working on one of those clear prison TVs from RCA. This particular one predates the digital tuner version and has a TA1268N inside. Looks like that one is commonly modded, so, so far so good. I want to use BNC connectors for RGBS on the back rather than SCART.

In trying to wrap my head around this chip, I took a look at the datasheet:
https://datasheetspdf.com/pdf-file/4929 ... /TA1268N/1

Can someone help me fully understand a few things?

Besides the RGB and blanking inputs on 14-17, I see the following interesting pins:

TV IN - 37
EXT VIDEO - 39
CHROMA IN - 45
Y IN - 43

I'm wondering where I might wire in my sync signal. This set does not have hardware inputs of any kind, only a tuner. The stock OSD does not have a way to switch to an external input.

I'm curious if perhaps I can mod this to also add an S-Video input too. The block diagram on the datasheet is what's confusing me though -- the TV IN and EXT VIDEO pins seem to only affect sync, and only the Y/C pins are actually being processed by the color/tint/brightness circuits. Is Y/C separation happening somewhere else? The example circuits near the end of the datasheet don't look wired up that way.

Thanks for this hugely helpful thread.
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DotMatrixMoe
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Re: TV RGB mod thread

Post by DotMatrixMoe »

culvos wrote:Hi, I'm working on one of those clear prison TVs from RCA. This particular one predates the digital tuner version and has a TA1268N inside. Looks like that one is commonly modded, so, so far so good. I want to use BNC connectors for RGBS on the back rather than SCART.

In trying to wrap my head around this chip, I took a look at the datasheet:
https://datasheetspdf.com/pdf-file/4929 ... /TA1268N/1

Can someone help me fully understand a few things?

Besides the RGB and blanking inputs on 14-17, I see the following interesting pins:

TV IN - 37
EXT VIDEO - 39
CHROMA IN - 45
Y IN - 43

I'm wondering where I might wire in my sync signal. This set does not have hardware inputs of any kind, only a tuner. The stock OSD does not have a way to switch to an external input.

I'm curious if perhaps I can mod this to also add an S-Video input too. The block diagram on the datasheet is what's confusing me though -- the TV IN and EXT VIDEO pins seem to only affect sync, and only the Y/C pins are actually being processed by the color/tint/brightness circuits. Is Y/C separation happening somewhere else? The example circuits near the end of the datasheet don't look wired up that way.

Thanks for this hugely helpful thread.
I think the Y IN (luma), is just fine for sync. As long it isn't CVBS (composite video sync) any console should be compatible. If you do need a CVBS source to plug in, using a sync stripper to convert it to ttl csync should be suitable as well.

As for the S Video mod, I think this chip has been written up on the S video mod thread. If I had a link, I'd be more than happy to drop it.
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culvos
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Re: TV RGB mod thread

Post by culvos »

DotMatrixMoe wrote:
culvos wrote:Hi, I'm working on one of those clear prison TVs from RCA. This particular one predates the digital tuner version and has a TA1268N inside. Looks like that one is commonly modded, so, so far so good. I want to use BNC connectors for RGBS on the back rather than SCART.

In trying to wrap my head around this chip, I took a look at the datasheet:
https://datasheetspdf.com/pdf-file/4929 ... /TA1268N/1

Can someone help me fully understand a few things?

Besides the RGB and blanking inputs on 14-17, I see the following interesting pins:

TV IN - 37
EXT VIDEO - 39
CHROMA IN - 45
Y IN - 43

I'm wondering where I might wire in my sync signal. This set does not have hardware inputs of any kind, only a tuner. The stock OSD does not have a way to switch to an external input.

I'm curious if perhaps I can mod this to also add an S-Video input too. The block diagram on the datasheet is what's confusing me though -- the TV IN and EXT VIDEO pins seem to only affect sync, and only the Y/C pins are actually being processed by the color/tint/brightness circuits. Is Y/C separation happening somewhere else? The example circuits near the end of the datasheet don't look wired up that way.

Thanks for this hugely helpful thread.
I think the Y IN (luma), is just fine for sync. As long it isn't CVBS (composite video sync) any console should be compatible. If you do need a CVBS source to plug in, using a sync stripper to convert it to ttl csync should be suitable as well.

As for the S Video mod, I think this chip has been written up on the S video mod thread. If I had a link, I'd be more than happy to drop it.
Thanks. Isn’t RGBS going to be TTL (5V)? I am worried about frying the chip.
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DotMatrixMoe
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Re: TV RGB mod thread

Post by DotMatrixMoe »

culvos wrote:
DotMatrixMoe wrote:
culvos wrote:Hi, I'm working on one of those clear prison TVs from RCA. This particular one predates the digital tuner version and has a TA1268N inside. Looks like that one is commonly modded, so, so far so good. I want to use BNC connectors for RGBS on the back rather than SCART.

In trying to wrap my head around this chip, I took a look at the datasheet:
https://datasheetspdf.com/pdf-file/4929 ... /TA1268N/1

Can someone help me fully understand a few things?

Besides the RGB and blanking inputs on 14-17, I see the following interesting pins:

TV IN - 37
EXT VIDEO - 39
CHROMA IN - 45
Y IN - 43

I'm wondering where I might wire in my sync signal. This set does not have hardware inputs of any kind, only a tuner. The stock OSD does not have a way to switch to an external input.

I'm curious if perhaps I can mod this to also add an S-Video input too. The block diagram on the datasheet is what's confusing me though -- the TV IN and EXT VIDEO pins seem to only affect sync, and only the Y/C pins are actually being processed by the color/tint/brightness circuits. Is Y/C separation happening somewhere else? The example circuits near the end of the datasheet don't look wired up that way.

Thanks for this hugely helpful thread.
I think the Y IN (luma), is just fine for sync. As long it isn't CVBS (composite video sync) any console should be compatible. If you do need a CVBS source to plug in, using a sync stripper to convert it to ttl csync should be suitable as well.

As for the S Video mod, I think this chip has been written up on the S video mod thread. If I had a link, I'd be more than happy to drop it.
Thanks. Isn’t RGBS going to be TTL (5V)? I am worried about frying the chip.

Csync won’t fry your chip, but raw TTL will.
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feltz
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Re: TV RGB mod thread

Post by feltz »

Hey all, long time lurker and first time poster. I'm getting ready to do my first RGB mod and wanted to clarify on a couple things.

First, going to be doing a RGB with OSD Mux on a Sony KV-27S42 using this method by MarkOLZAD :
viewtopic.php?p=1342960#p1342960

My only usage for this RGB mod will be feeding it from a CRTEmudriver / Groovymame VGA card for arcade cabinet.

My understanding is that the RBG levels on VGA is accurate, but sync is TTL so its at 5v, and TV needs 0.3vpp. The driver has the option for CSync, but its somewhat unreliable so based on scattered reading i hear its best to drop the voltage of both h /v sync using 1k ohm resistors, then combine those lines after and feed into s-video luma input?

Also, I am planning mounting a female DB15 port on the back of the TV, since i only plan on using this to interface with a VGA 15khz signal.
I wanted to preserve the option of plugging in S-Video when RGB is not in use, so thoughts were to use a DPST switch for blanking, as well as s-video sense for sync.
Is there an issue if i leave the sync line connected or should i also hook that up to a switch? I want to be able to flip the switch and use S-video normally..

Thanks ahead of time!
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DotMatrixMoe
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Re: TV RGB mod thread

Post by DotMatrixMoe »

feltz wrote:Hey all, long time lurker and first time poster. I'm getting ready to do my first RGB mod and wanted to clarify on a couple things.

First, going to be doing a RGB with OSD Mux on a Sony KV-27S42 using this method by MarkOLZAD :
viewtopic.php?p=1342960#p1342960

My only usage for this RGB mod will be feeding it from a CRTEmudriver / Groovymame VGA card for arcade cabinet.

My understanding is that the RBG levels on VGA is accurate, but sync is TTL so its at 5v, and TV needs 0.3vpp. The driver has the option for CSync, but its somewhat unreliable so based on scattered reading i hear its best to drop the voltage of both h /v sync using 1k ohm resistors, then combine those lines after and feed into s-video luma input?

Also, I am planning mounting a female DB15 port on the back of the TV, since i only plan on using this to interface with a VGA 15khz signal.
I wanted to preserve the option of plugging in S-Video when RGB is not in use, so thoughts were to use a DPST switch for blanking, as well as s-video sense for sync.
Is there an issue if i leave the sync line connected or should i also hook that up to a switch? I want to be able to flip the switch and use S-video normally..

Thanks ahead of time!
I use Csync via CRT Emudriver 24/7. Just make sure to change sync polarities positive. Haven't had an issue yet, so I'd stick with that. (Windows 7 CRT Emudriver 2.0 is what I use). If you decide to go your route however, a really cool idea is to put this circuit inside your TV so every cable doesn't require it built in it: https://www.retrorgb.com/building-a-pas ... biner.html

As for S video, I had really good luck just hooking up the S video ground to SCART ground so that sense is activated immediately upon plugin. However, I just stuck with composite due to its simplicity.
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feltz
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Re: TV RGB mod thread

Post by feltz »

DotMatrixMoe wrote:
I use Csync via CRT Emudriver 24/7. Just make sure to change sync polarities positive. Haven't had an issue yet, so I'd stick with that. (Windows 7 CRT Emudriver 2.0 is what I use). If you decide to go your route however, a really cool idea is to put this circuit inside your TV so every cable doesn't require it built in it: https://www.retrorgb.com/building-a-pas ... biner.html

As for S video, I had really good luck just hooking up the S video ground to SCART ground so that sense is activated immediately upon plugin. However, I just stuck with composite due to its simplicity.
I was reading on arcadecontrols of some people having issues with Csync on boot, when using atom-15 bios, which is why i wanted to avoid that route. Do you use atom-15 bios as well?
After reading the article, it sounds like outputting CSync is going to be the safest route for compatibility, specially when working with interlace content (since im on an NTSC TV, i expect that to occur quite often, for vertical games, etc)
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DotMatrixMoe
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Re: TV RGB mod thread

Post by DotMatrixMoe »

feltz wrote:
DotMatrixMoe wrote:
I use Csync via CRT Emudriver 24/7. Just make sure to change sync polarities positive. Haven't had an issue yet, so I'd stick with that. (Windows 7 CRT Emudriver 2.0 is what I use). If you decide to go your route however, a really cool idea is to put this circuit inside your TV so every cable doesn't require it built in it: https://www.retrorgb.com/building-a-pas ... biner.html

As for S video, I had really good luck just hooking up the S video ground to SCART ground so that sense is activated immediately upon plugin. However, I just stuck with composite due to its simplicity.
I was reading on arcadecontrols of some people having issues with Csync on boot, when using atom-15 bios, which is why i wanted to avoid that route. Do you use atom-15 bios as well?
After reading the article, it sounds like outputting CSync is going to be the safest route for compatibility, specially when working with interlace content (since im on an NTSC TV, i expect that to occur quite often, for vertical games, etc)
Unfortunately I also have no sync on boot. To combat this, I changed some settings to boot directly onto Windows 7. This makes the loss of V sync very brief.
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MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

culvos wrote:Hi, I'm working on one of those clear prison TVs from RCA. This particular one predates the digital tuner version and has a TA1268N inside. Looks like that one is commonly modded, so, so far so good. I want to use BNC connectors for RGBS on the back rather than SCART.

In trying to wrap my head around this chip, I took a look at the datasheet:
https://datasheetspdf.com/pdf-file/4929 ... /TA1268N/1

Can someone help me fully understand a few things?

Besides the RGB and blanking inputs on 14-17, I see the following interesting pins:

TV IN - 37
EXT VIDEO - 39
CHROMA IN - 45
Y IN - 43

I'm wondering where I might wire in my sync signal. This set does not have hardware inputs of any kind, only a tuner. The stock OSD does not have a way to switch to an external input.

I'm curious if perhaps I can mod this to also add an S-Video input too. The block diagram on the datasheet is what's confusing me though -- the TV IN and EXT VIDEO pins seem to only affect sync, and only the Y/C pins are actually being processed by the color/tint/brightness circuits. Is Y/C separation happening somewhere else? The example circuits near the end of the datasheet don't look wired up that way.

Thanks for this hugely helpful thread.
If the set is RF only it will currently be sending sync in through the TV IN. I have modded similar chips and have found that sync can be sent into the TV in pin, this chip looks like it can take audio into pin 53 so that might be good too.

There should be a capacitor connected to the TV IN, if it is through hole type, could lift the leg farthest from jungle and then input 75 ohm terminated sync into it.

I have seen issues when you try and use a tuner's TV input where it cannot find a signal and tries to pump up the gain and cause interference. Not sure if that will happen here. Could possibly remove the tuner to prevent that.

If it were my set I'd be trying to find a way into the service menu. If you could get into there you might be able to enable the external inputs, possibly even S-Video. Then you could use the external pins. Unless these are enabled in the service menu you are unlikely to have any success using them as the jungle requires serial commands sent to it to enable them***.

Another thing you need to confirm is if the set has a live chassis. A dead giveaway is a transformer on the antenna input. If it's live chassis you will need an isolation transformer to prevent the TV shorting out through the console.


*** An I2C serial hack could be used to enable the external inputs/S-Video. this is getting into the more advanced modding techniques.
___________________________________________________
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
culvos
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Re: TV RGB mod thread

Post by culvos »

MarkOZLAD wrote:
culvos wrote:Hi, I'm working on one of those clear prison TVs from RCA. This particular one predates the digital tuner version and has a TA1268N inside. Looks like that one is commonly modded, so, so far so good. I want to use BNC connectors for RGBS on the back rather than SCART.

In trying to wrap my head around this chip, I took a look at the datasheet:
https://datasheetspdf.com/pdf-file/4929 ... /TA1268N/1

Can someone help me fully understand a few things?

Besides the RGB and blanking inputs on 14-17, I see the following interesting pins:

TV IN - 37
EXT VIDEO - 39
CHROMA IN - 45
Y IN - 43

I'm wondering where I might wire in my sync signal. This set does not have hardware inputs of any kind, only a tuner. The stock OSD does not have a way to switch to an external input.

I'm curious if perhaps I can mod this to also add an S-Video input too. The block diagram on the datasheet is what's confusing me though -- the TV IN and EXT VIDEO pins seem to only affect sync, and only the Y/C pins are actually being processed by the color/tint/brightness circuits. Is Y/C separation happening somewhere else? The example circuits near the end of the datasheet don't look wired up that way.

Thanks for this hugely helpful thread.
If the set is RF only it will currently be sending sync in through the TV IN. I have modded similar chips and have found that sync can be sent into the TV in pin, this chip looks like it can take audio into pin 53 so that might be good too.

There should be a capacitor connected to the TV IN, if it is through hole type, could lift the leg farthest from jungle and then input 75 ohm terminated sync into it.

I have seen issues when you try and use a tuner's TV input where it cannot find a signal and tries to pump up the gain and cause interference. Not sure if that will happen here. Could possibly remove the tuner to prevent that.

If it were my set I'd be trying to find a way into the service menu. If you could get into there you might be able to enable the external inputs, possibly even S-Video. Then you could use the external pins. Unless these are enabled in the service menu you are unlikely to have any success using them as the jungle requires serial commands sent to it to enable them***.

Another thing you need to confirm is if the set has a live chassis. A dead giveaway is a transformer on the antenna input. If it's live chassis you will need an isolation transformer to prevent the TV shorting out through the console.


*** An I2C serial hack could be used to enable the external inputs/S-Video. this is getting into the more advanced modding techniques.
Thanks. I haven't done this sort of mod before to a CRT TV, but I am handy at other electronic stuff and thought of the I2C thing myself. I think I could setup an Arduino or even an RPi inside to talk to the i2c bus and swap the input that way. Honestly I think it would be fine to just stick to RGB-only, with OSD muxing if possible, since this is a gift for a friend who will most likely only ever use it as RGB. It is a hilarious idea to have a prison TV with a web interface, though (reminds me of the DCDigital for the Dreamcast). The TV does actually have an IR receiver on it; I could try some IR codes to see if that works but I doubt it goes anywhere.

Can I get a gut check on what style of sync to use? My setup at home is a PVM using an Extron; all my stuff is thus TTL sync and all BNC. This prison TV is a gift for a friend of mine, and most likely what he will do is hang a SCART to BNC adapter off the back. I know he has mostly SCART cables and a SCART switcher. His current setup is running through a Framemeister so I assume sync-over-composite at those levels is what is already provided by what he has today.

But, ideally, this set's input works just like a PVM, which I presume expects TTL sync. Or maybe there is a way to have this set accept both? I am definitely not an analog signals guy so this is the big question. It would be great to maximize compatibility.

I have seen several people ask about these TVs, both here and on Reddit. I plan to write this up once I'm done so maybe it will save some people future effort. Thanks for the help!

Edit: More info on this model, S13801CL. It is a TX808 chassis (subtype G), which is well-documented with schematics. The only difference I see here between this and similar models with inputs is (a) the microcontroller, which would have a different mask ROM on it for the prison models, and (b) the absence of the input jacks on the back. The passives for the inputs are actually all populated on the board, so theoretically you could swap in a different TX808 compatible microcontroller and add the standard jack part to the board to get composite in. Neat! (Or, of course, drop in an Arduino and a pushbutton to send the i2c command to the jungle). Also from the schematics I was able to confirm what you already suggested, which is the TV_IN pin is composite video either from the external input or the TV tuner. With that pin lifted, it will likely work as the sync source, but I just wanted to get your thoughts on the above regarding TTL compatibility.

There is a very simple service menu but it is purely for tube calibration. The bits for the input(s) are in the mask ROM on the microcontroller.

I'd also like to ask about the dimming of the display related to closed-captioning. I can tell when the menu is opened the display dims, and I'm guessing it's some function of that same circuit. In the 8-Bit Guy video, he mentioned someone told him to jumper two pins to disable the CC dimming; any idea what pins those should be?
feltz
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Re: TV RGB mod thread

Post by feltz »

Wondering of someone can help confirm this is the right setup blanking switch on KV-27S42 before i power it on and blow something up !
Only info i saw was hand written note and no pics.

Image
feltz
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Re: TV RGB mod thread

Post by feltz »

Ah poop i must have done something wrong. Its mostly working? I cant fully tell but it looks like maybe only one signal is getting through, i know this image looks blue but in person it almost looks b/w.

Any ideas what i messed up?

Image
KPackratt2k
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Re: TV RGB mod thread

Post by KPackratt2k »

culvos wrote:Edit: More info on this model, S13801CL. It is a TX808 chassis (subtype G), which is well-documented with schematics. The only difference I see here between this and similar models with inputs is (a) the microcontroller, which would have a different mask ROM on it for the prison models, and (b) the absence of the input jacks on the back. The passives for the inputs are actually all populated on the board, so theoretically you could swap in a different TX808 compatible microcontroller and add the standard jack part to the board to get composite in. Neat! (Or, of course, drop in an Arduino and a pushbutton to send the i2c command to the jungle). Also from the schematics I was able to confirm what you already suggested, which is the TV_IN pin is composite video either from the external input or the TV tuner. With that pin lifted, it will likely work as the sync source, but I just wanted to get your thoughts on the above regarding TTL compatibility.

There is a very simple service menu but it is purely for tube calibration. The bits for the input(s) are in the mask ROM on the microcontroller.

I'd also like to ask about the dimming of the display related to closed-captioning. I can tell when the menu is opened the display dims, and I'm guessing it's some function of that same circuit. In the 8-Bit Guy video, he mentioned someone told him to jumper two pins to disable the CC dimming; any idea what pins those should be?
If you have an EEPROM programmer and some spare 24C04W6 compatible ROM chips, you might want to try flashing this firmware onto a spare 24C04W6 compatible chip and replace the IR02 chip with your substitute chip with the new firmware flashed onto it:

https://shema.info/en/firmware/26137-pr ... -9635.html

This firmware enabled the AV input functionality on my RCA E13309 TV with a TX808A chassis, so it might help with your set. Be aware that the inline resistors are surface mount, so your easiest route would be to put your resistors onto a small breadboard and wire it in place of the original inline resistors. As for closed captioning dimming, there was no need to disable it (and AFAIK there are no pins for that specific feature on this chassis).

Here's a link to my old post which contains details on how I've modded my set. I used RCA jacks, but the procedure should be the same for BNC:
viewtopic.php?f=6&t=56155&p=1451968#p1451968
feltz
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Re: TV RGB mod thread

Post by feltz »

Ok looks like i had a similar issue to others, where i only get an full image when Menu is enabled.
Found this post: viewtopic.php?f=6&t=56155&start=3120

Looks like at least 3 of us have ran into this, maybe MarkOZLAD can update the original writeup as an alternative?

Gonna we-wire the blanking line now, but man does this look great. Sorry for the glare in the image!
Image
culvos
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Re: TV RGB mod thread

Post by culvos »

KPackratt2k wrote:
culvos wrote:Edit: More info on this model, S13801CL. It is a TX808 chassis (subtype G), which is well-documented with schematics. The only difference I see here between this and similar models with inputs is (a) the microcontroller, which would have a different mask ROM on it for the prison models, and (b) the absence of the input jacks on the back. The passives for the inputs are actually all populated on the board, so theoretically you could swap in a different TX808 compatible microcontroller and add the standard jack part to the board to get composite in. Neat! (Or, of course, drop in an Arduino and a pushbutton to send the i2c command to the jungle). Also from the schematics I was able to confirm what you already suggested, which is the TV_IN pin is composite video either from the external input or the TV tuner. With that pin lifted, it will likely work as the sync source, but I just wanted to get your thoughts on the above regarding TTL compatibility.

There is a very simple service menu but it is purely for tube calibration. The bits for the input(s) are in the mask ROM on the microcontroller.

I'd also like to ask about the dimming of the display related to closed-captioning. I can tell when the menu is opened the display dims, and I'm guessing it's some function of that same circuit. In the 8-Bit Guy video, he mentioned someone told him to jumper two pins to disable the CC dimming; any idea what pins those should be?
If you have an EEPROM programmer and some spare 24C04W6 compatible ROM chips, you might want to try flashing this firmware onto a spare 24C04W6 compatible chip and replace the IR02 chip with your substitute chip with the new firmware flashed onto it:

https://shema.info/en/firmware/26137-pr ... -9635.html

This firmware enabled the AV input functionality on my RCA E13309 TV with a TX808A chassis, so it might help with your set. Be aware that the inline resistors are surface mount, so your easiest route would be to put your resistors onto a small breadboard and wire it in place of the original inline resistors. As for closed captioning dimming, there was no need to disable it (and AFAIK there are no pins for that specific feature on this chassis).

Here's a link to my old post which contains details on how I've modded my set. I used RCA jacks, but the procedure should be the same for BNC:
viewtopic.php?f=6&t=56155&p=1451968#p1451968
Oh, this is great. I do have an EEPROM programmer. I'll definitely give this a shot. Thank you!

(Why not just backup the old chip and rewrite it?)
culvos
Posts: 9
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Re: TV RGB mod thread

Post by culvos »

KPackratt2k wrote:
culvos wrote:Edit: More info on this model, S13801CL. It is a TX808 chassis (subtype G), which is well-documented with schematics. The only difference I see here between this and similar models with inputs is (a) the microcontroller, which would have a different mask ROM on it for the prison models, and (b) the absence of the input jacks on the back. The passives for the inputs are actually all populated on the board, so theoretically you could swap in a different TX808 compatible microcontroller and add the standard jack part to the board to get composite in. Neat! (Or, of course, drop in an Arduino and a pushbutton to send the i2c command to the jungle). Also from the schematics I was able to confirm what you already suggested, which is the TV_IN pin is composite video either from the external input or the TV tuner. With that pin lifted, it will likely work as the sync source, but I just wanted to get your thoughts on the above regarding TTL compatibility.

There is a very simple service menu but it is purely for tube calibration. The bits for the input(s) are in the mask ROM on the microcontroller.

I'd also like to ask about the dimming of the display related to closed-captioning. I can tell when the menu is opened the display dims, and I'm guessing it's some function of that same circuit. In the 8-Bit Guy video, he mentioned someone told him to jumper two pins to disable the CC dimming; any idea what pins those should be?
If you have an EEPROM programmer and some spare 24C04W6 compatible ROM chips, you might want to try flashing this firmware onto a spare 24C04W6 compatible chip and replace the IR02 chip with your substitute chip with the new firmware flashed onto it:

https://shema.info/en/firmware/26137-pr ... -9635.html

This firmware enabled the AV input functionality on my RCA E13309 TV with a TX808A chassis, so it might help with your set. Be aware that the inline resistors are surface mount, so your easiest route would be to put your resistors onto a small breadboard and wire it in place of the original inline resistors. As for closed captioning dimming, there was no need to disable it (and AFAIK there are no pins for that specific feature on this chassis).

Here's a link to my old post which contains details on how I've modded my set. I used RCA jacks, but the procedure should be the same for BNC:
viewtopic.php?f=6&t=56155&p=1451968#p1451968
I gave the EEPROM reflash a shot. Your model, E13309, is a TX808(A) model. In the TX808 parts list, you can see that the microcontroller subcode for the A model as well as many others (K,J,H,D,C,B,E,A,R) is the same. It probably flips some settings around based on the contents of the EEPROM, but ultimately there is different microcontroller code on these models vs. the G (SecureView) models. On the SecureView cut sheet, they indicate that the clock is disabled, for one thing. I guess clocks are not allowed in prisons? So that whole menu entry for the clock, as well as timer stuff, is gone from the set. There's no telling whether RCA engineers decided to disable the external video input option here. My gut says they just patched out the clock code and called it a day, though.

So how are you switching input to composite on your modded E13309? I found a few videos of the E13320 online which is an H type set (the same type you flashed your EEPROM with) and people use the "Input" button on the remote; maybe it's also possible to go down from channel 1/2/3 to switch to the input. On this G model and on your unmodded E13309, pressing "Input" on the remote sends the TV to cycle through channels 3/4, as if you have an RF modulator attached. I also found the manual for your E13309 and it says it behaves that way (input on remote = change to channel 3/4). When you flashed your EEPROM did the remote behavior change?

tl;dr: My hunch here is that your set uses a microcontroller with code that is reused across many models of this TV, and the microcontroller on the SecureView series has different code. Even if the SecureView still has the same code path for enabling the external video input with some flag in the EEPROM, that flag may be in a different position. I'd like to figure that out, because if that is the case I could provide a modded EEPROM image for other SecureView users to flash and avoid needing to swap boards or microcontrollers to enable the input. Of course, an RGB-only mod can still be done without any of this. It's just nicer to have the input working too
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

feltz wrote:maybe MarkOZLAD can update the original writeup as an alternative?
Happy to. Just tell me the exact changes you want me to make and I'll try to get around to 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
culvos
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Re: TV RGB mod thread

Post by culvos »

Another progress update. After putting the EEPROM idea on ice, I looked for a place to do the sync. TV_IN was not working; the sync seemed to be at the wrong level, so a test composite input was flickering and rolling. It also seemed to confuse the whole system in terms of whether a channel was tuned, presumably because it wasn't detecting a sync lock.

So what I did was hook up a VCR to the tuner and put it on a still frame, then compared the Vpp at different areas to see what the level should look like with a good signal; the issue was the the sync was too low as-is and needed to be amplified by a transistor slightly upstream before it entered TV_IN.

See this hideously-marked-up graphic for what I did:
Image

Basically by removing RI532, RI528, and CI525, it isolates the tuner circuit's CVBS output. Then into the center leg of TI21 we can insert composite here and, voila, every "channel" in TV tuner mode is now that composite input. Similarly you can input composite sync on its own here, and it works in RGB mode too. Without this extra amplification step I was unable to get sync working properly.

So now that we have a good sync input I turned to doing the OSD mux stuff. I used your spreadsheet, MarkOZLAD. The factory in-line resistors on the TX808 series are 3.3k. By the math on the sheet (no diodes) I came to a value of 470 for the new mux resistors. I removed the grounding resistors as instructed, added the 470's and 75's for grounding, and it worked! We have RGB, and the OSD works! But it is pretty dim. I am wondering if possibly the suggestion of "Existing TV capacitors may need to be replaced with 100nF" applies here. The existing caps are 22nF. Would that cause dimming?

For reference here is the area of interest where the RGB tapping is occurring. I have marked up just one of the lines to show you how my resistors are set up.
Image

Before modification, the inline resistors (3.3k) and the grounding resistors (820) were creating a voltage divider from 5V->1V into the jungle. Could it be this jungle chip wants to see 1V on the RGB input lines, and we're overdoing it shooting for 0.7 Vpp?
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

culvos wrote:
Before modification, the inline resistors (3.3k) and the grounding resistors (820) were creating a voltage divider from 5V->1V into the jungle. Could it be this jungle chip wants to see 1V on the RGB input lines, and we're overdoing it shooting for 0.7 Vpp?
The cheaters method to choosing mux resistors is to subtract 75 from the factory "grounding resistor" value and take the next standard size up.

So in this case (820-75)=745 ...therefore 750R. I'd give that a go.
___________________________________________________
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
feltz
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Re: TV RGB mod thread

Post by feltz »

MarkOZLAD wrote:
feltz wrote:maybe MarkOZLAD can update the original writeup as an alternative?
Happy to. Just tell me the exact changes you want me to make and I'll try to get around to it.
The details from rage8885's post:
viewtopic.php?f=6&t=56155&start=3120

Which started from Tengugurl's post:
viewtopic.php?p=1410607#p1410607

The change that fixed it for me, was removing the 1k resistor off of the blanking line, run it directly to pin 49 of IC001 and pull +5v from near the AV port.
culvos
Posts: 9
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Re: TV RGB mod thread

Post by culvos »

MarkOZLAD wrote:
culvos wrote:
Before modification, the inline resistors (3.3k) and the grounding resistors (820) were creating a voltage divider from 5V->1V into the jungle. Could it be this jungle chip wants to see 1V on the RGB input lines, and we're overdoing it shooting for 0.7 Vpp?
The cheaters method to choosing mux resistors is to subtract 75 from the factory "grounding resistor" value and take the next standard size up.

So in this case (820-75)=745 ...therefore 750R. I'd give that a go.
No good on that either. The built-in circuit is clearly tuned to provide 1V to the jungle. I think the 0.7Vpp is too low. I have seen some posts about a different jungle chip that had a "digital OSD" mode that expected 1V, the LA768XX series. It sure looks to me like this jungle, TA1268N, expects the same.

But then that raises the question of how other people modded the same TX808 chassis and were happy with their mods without an amplification step or adjustment somewhere. Did they just crank up their tubes and call it a day?

I found multiple posts about the Sharp 13K-M100 that uses the Sharp IX2933CE which is a TA1268N clone. Everyone has said the same, that it expects 1V, and will be dim if this is not corrected in some way.

I think the person who modded his TX808 and flashed the EEPROM, who also mentioned having issues with "excessive brightness possibly due to a faulty flyback" likely has his display over driven and that's why it doesn't look dim to him.

I am going to attempt to use a 180R to terminate instead of 75, to get that voltage up to 1V, and mux with an 820R as a result (have added diodes). Will update after that.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

culvos wrote:
MarkOZLAD wrote:
culvos wrote:
Before modification, the inline resistors (3.3k) and the grounding resistors (820) were creating a voltage divider from 5V->1V into the jungle. Could it be this jungle chip wants to see 1V on the RGB input lines, and we're overdoing it shooting for 0.7 Vpp?
The cheaters method to choosing mux resistors is to subtract 75 from the factory "grounding resistor" value and take the next standard size up.

So in this case (820-75)=745 ...therefore 750R. I'd give that a go.
No good on that either. The built-in circuit is clearly tuned to provide 1V to the jungle. I think the 0.7Vpp is too low. I have seen some posts about a different jungle chip that had a "digital OSD" mode that expected 1V, the LA768XX series. It sure looks to me like this jungle, TA1268N, expects the same.

But then that raises the question of how other people modded the same TX808 chassis and were happy with their mods without an amplification step or adjustment somewhere. Did they just crank up their tubes and call it a day?

I found multiple posts about the Sharp 13K-M100 that uses the Sharp IX2933CE which is a TA1268N clone. Everyone has said the same, that it expects 1V, and will be dim if this is not corrected in some way.

I think the person who modded his TX808 and flashed the EEPROM, who also mentioned having issues with "excessive brightness possibly due to a faulty flyback" likely has his display over driven and that's why it doesn't look dim to him.

I am going to attempt to use a 180R to terminate instead of 75, to get that voltage up to 1V, and mux with an 820R as a result (have added diodes). Will update after that.
I thought you were saying the OSD is dim.
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MarkOZLAD
OSD/External RGB Mux Diagram
OSD/External RGB Mux Resistor Value Table 0.7Vp-p : 0.5Vp-p

"Imagine toggle switch OSD modding a TV in 2019" - maxtherabbit
culvos
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Re: TV RGB mod thread

Post by culvos »

Oh! Man, I even thought that might be poorly communciated as I typed it and I forgot to edit it.

Yes, the entire display is dim! The OSD is slightly brighter, and on the scope I can see the OSD areas peeking out at the higher Vpp.

I did find a counter-example 13K-M100 post here:
viewtopic.php?p=1424154#p1424154

No idea how his isn't dim like mine, unless possibly the flyback is adjusted to compensate.
MarkOZLAD
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Re: TV RGB mod thread

Post by MarkOZLAD »

culvos wrote:unless possibly the flyback is adjusted to compensate.
That's the first thing I'd try.
___________________________________________________
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
culvos
Posts: 9
Joined: Sun Jan 09, 2022 1:12 am

Re: TV RGB mod thread

Post by culvos »

MarkOZLAD wrote:
culvos wrote:unless possibly the flyback is adjusted to compensate.
That's the first thing I'd try.
I got to 1Vpp with the 180R terminator in my previous post (terminating with 180R; and therefore muxing with 820R), and it was juuuust a bit too bright (blowing out some grays on the pluge), and adjusting the flyback a tiny bit brought us to perfect! It looks great!

I'm obviously a noob here, but wondering if you think it's better to have used the nominal voltage to the jungle to reduce the amount of overdrive on the tube -- I would assume overdriving the tube would limit its life, but not sure if it would be a meaningful amount.

Since that leg on TI21 worked well for composite and sync, I have added a composite "input" by including it on the RGB switch (using a 3PDT). So now with a single switch you can flip between composite input and RGB, and both have their own audio-in lines. I'm also adding a second switch for sync attenuation (TTL vs. 75ohm).

The OSD muxing looks and works great, but ultimately it's really only useful for the volume overlay and the service menu. None of the other settings will affect RGB mode. Using the service menu (and the flyback) I was able to make everything perfect with 240p test suite.

Thanks again MarkOZLAD, it's very cool you have been so patient and helpful in this thread with so many people.

I will be back with photos once I finish adding the switches and cleaning up my wiring harnesses.
feltz
Posts: 7
Joined: Thu Jan 06, 2022 9:19 pm

Re: TV RGB mod thread

Post by feltz »

Hey guys, for some reason I am unable to go into my service menu after RGB OSD mux.
The non-service menu seems to be working fine, but PowerOff->display->5->volUp->PowerOn just turns it on normally.
jd213
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Location: Pennsylvania

Re: TV RGB mod thread

Post by jd213 »

Recently got a Sony KV-24CW1 here in Japan, a nice 24" widescreen model from 1998 but only has composite and S-Video (no PS connector shaped RGB input like some Trinitrons had in Japan).

Couldn't find the service manual anywhere, is there a way to determine what chassis it has? Here's a pic if it helps (pardon the dust, I cleaned it after taking the pic):

Image
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