TV RGB mod thread

[MarkOZLAD]

And I was still able to switch AV channels using the TV front panel, so I guess, this means no blanking, right?

From my experience the AV switches will still work when blanking occurs, however on all the other channels you get no sync and a rolling picture.

[Syntax]

Having a bit of a wtf moment and need some help.

An LG I modded to take RGB which was an easy mod, had an unpopulated scart port, is only showing a black and white picture on my csync consoles.

Using composite video as sync shows a perfect RGB picture. I've made sure this wasn't composite.

[evilsim]

Ive spent a few hours still trying with this Sony KV-XJ29M31. The jungle is a CXA2159S and below it is the CXP86461 dip. I have tried to remove the whole teletext board and solder onto those points, also tried to solder direct onto the CXa2159S rgb in points. I see colours from the consoles ive tested but no solid sync still.. Have also soldered .1 ceramic caps to the RGB lines. Tried all the sync points I can find incl pin 4 and 8 of the CXA and all the external AV1/2 and Y of the YPbPr port... Also putting 5v or 9v on the BLK pin doesnt seem to change anything, on any channel or teletext.

ALmost at the point where im just going to build a ba7230ls based SCART to YUV board to use with this telly.

Does anyone have any other ideas of where I can find sync on this set I have tested with CSYNC and Composite-Sync and various consoles incl ones with RGB output from the factory (SFami, MD2, etc)

[MarkOZLAD]

Ive spent a few hours still trying with this Sony KV-XJ29M31. The jungle is a CXA2159S and below it is the CXP86461 dip. I have tried to remove the whole teletext board and solder onto those points, also tried to solder direct onto the CXa2159S rgb in points. I see colours from the consoles ive tested but no solid sync still.. Have also soldered .1 ceramic caps to the RGB lines. Tried all the sync points I can find incl pin 4 and 8 of the CXA and all the external AV1/2 and Y of the YPbPr port... Also putting 5v or 9v on the BLK pin doesnt seem to change anything, on any channel or teletext.

ALmost at the point where im just going to build a ba7230ls based SCART to YUV board to use with this telly.

Does anyone have any other ideas of where I can find sync on this set I have tested with CSYNC and Composite-Sync and various consoles incl ones with RGB output from the factory (SFami, MD2, etc)

I'm really surprised you haven't got this to work. I modded one a while back and it was straightforward. Could use csync or composite video for sync straight into the AV1, AV2 or Component Green. (I don't have luma sync to test with)

RGB lines with 75ohm terminations to ground go straight onto the RGB Teletext ports, there's a spot for blanking too. If you left the teletext board in place you should've been able to get blanking to work by pressing the teletext. (now that I've learned more I likely would add some resistance to my RGB lines to help the OSD)

What happens if you just put sync into an AV port? Do you get a ghost image? When I do my mods I always pass the sync and sync ground back to an RCA cable to plug in to the AV port.

Should be same process as for this set.

Happy to help you with this.

[evilsim]

Thx MarkOZLAD. I do get a ghost image if I put sync into the AV or Y ports (pure sync, and an image if composite sync, or B&W image if in the Y port). I also solder on a RCA end, for signal and GND in testing
I had already seen and studied your post on the same chassis - adding more to my confusion of why mine isn't working. I will try and have another crack at this next week, taking note of your comment on testing the blanking on the teletext, as I have not done this exact test.
My TV chassis looks identical to Syntax's as in this post viewtopic.php?p=1276013#p1276013 the RGB lines where he has added the 104 cap's are identical to my tv, although he doesn't seem to be using the blanking pin, which is the one I am pulling high to 5v in my set.

cheers, will reply with findings next time

[fandangos]

Still trying to figure things out with this Panasonic.

The schematics show AV3 (component) going to connector A100 (which is a component board that does Y Pb Pr to Y B-Y R-Y) and only after it goes to pins 51, 52, 53.
So I removed the board and did a bypass.

I'm using a 10k pot wired to 5v to deliver to pin INSSW2 50 2nd RGB / YUV insertion input.
And I'm using a Y cable to give sync with Green.

I can get a steady picture, with proper sync but black and white....

Here you can see the bypass:

Here with the pot turned to maximum resistance:

Here the pot allowing 5v to be delivered:


I`m using a consolized MVS to avoid having composite sync.

EDIT:

Could someone try to answer this questions?

1. INSW2 isn't a blanking pin. It's a pin so switch states from YUV to something else. If I'm using the AV3 (component) and this input already exists and I can select it, do I need to blank anything?
If yes, what's the correct blanking pin?

2. I've added a 10k pot resistor to pin 50 INSW and it change states, I'm using 5v. But I soldered it to the pin without lifting it's leg, so I guess it is still receiving the normal 2v + 5v?
Should I disconnect it and solder only the 5v from the pot to that pin?

EDIT 2: The thing is the INSW is changing from YUV to composite and not RGB.
I tested the input on AV1 with Green + sync and the result is the same black and white picture.

[Shan#]

Hi, does anyone have any pinout details for JVC D-series rgb modding? I have this tv and like it alot

[takeshi385]

One more question the blanking pin on the Sony CXA2025AS jungle chip is YS correct?
http://pdf1.alldatasheet.com/datasheet- ... 025AS.html

[xAzurexEonx]

Hi, does anyone have any pinout details for JVC D-series rgb modding? I have this tv and like it alot

viewtopic.php?f=6&t=56155&start=403

[fandangos]

So I found this datasheet of the TDA9552H and it's identical to the tda9592h/n3/3/1502 pinout.

There's no publicly available datasheet for the tda9592h/n3/3/1502 that my panasonic has.

http://www.datasheetspdf.com/PDF/TDA9552H/870544/8

I'm starting to think that the TV when receiving 5+ volts to Pin 50 INSSW2, changes from YUV to composite because of a EEPROM bit somewhere.
I can enter the Service Menu and direct write values to the EEPROM.

The datasheet claims:
• A linear RGB/YUV/YPBPR input with fast blanking for
external RGB/YUV sources. The synchronisation circuit
can be connected to the incoming Y signal.

And:
RGB output circuit and black-current stabilization
In the RGB control circuit the signal is controlled on
contrast, brightness and saturation. The ICs have a linear
input for external RGB/YUV signals. Switching between
RGB and the YUV/YPRPB mode can be realised via the
YUV0/YUV1 bits in subaddress 2BH.

This means HEX address 02B which in my TV is 0 0.
That makes sense because the Jungle IC outputs RGB (at 2V).

I need to change it on the input side.


The thing is, is there any way to find out what BIT should I change to enable RGB instead of YUV?
There's a table that says:
Table 94 Enable vertical guard (RGB blanking) 0 and 1, inactive and active.

The Panasonic MS_TC-29FJ30L datahseet has all the values of the EEPROM but no indication of what they are for.

Please, any ideas?

[MarkOZLAD]

So I found this datasheet of the TDA9552H and it's identical to the tda9592h/n3/3/1502 pinout.

There's no publicly available datasheet for the tda9592h/n3/3/1502 that my panasonic has.

http://www.datasheetspdf.com/PDF/TDA9552H/870544/8

I'm starting to think that the TV when receiving 5+ volts to Pin 50 INSSW2, changes from YUV to composite because of a EEPROM bit somewhere.
I can enter the Service Menu and direct write values to the EEPROM.

The datasheet claims:
• A linear RGB/YUV/YPBPR input with fast blanking for
external RGB/YUV sources. The synchronisation circuit
can be connected to the incoming Y signal.

And:
RGB output circuit and black-current stabilization
In the RGB control circuit the signal is controlled on
contrast, brightness and saturation. The ICs have a linear
input for external RGB/YUV signals. Switching between
RGB and the YUV/YPRPB mode can be realised via the
YUV0/YUV1 bits in subaddress 2BH.

This means HEX address 02B which in my TV is 0 0.
That makes sense because the Jungle IC outputs RGB (at 2V).

I need to change it on the input side.


The thing is, is there any way to find out what BIT should I change to enable RGB instead of YUV?
There's a table that says:
Table 94 Enable vertical guard (RGB blanking) 0 and 1, inactive and active.

The Panasonic MS_TC-29FJ30L datahseet has all the values of the EEPROM but no indication of what they are for.

Please, any ideas?

I've had a bit of a go at understanding the I2C communication in the TVs.

One thing I discovered that the addresses listed in the datasheets for the configuration bits do not directly relate to the EEPROM maps. Instead I believe you need to put an I2C device onto the TVs I2C bus and send I2C read and write commands to the chips using the addresses supplied (8A for write, 8B for read).

I haven't successfully managed to do this yet though I haven't spent a lot of time on it either. I was able to get a response from the TV but wasn't able to achieve anything constructive.

[Shan#]

Hi, does anyone have any pinout details for JVC D-series rgb modding? I have this tv and like it alot

viewtopic.php?f=6&t=56155&start=403

Thanks, I had seen that but the resolution was to low to read, I think I can figure it out though

[takeshi385]

If I am right that YS is the blanking pin for the sony cxa2025as jungle chip, then it looks like I will have to step down the vcc from 9v to 3v since appears to be the max high for the ys blanking pin. Can someone else please double check the pinout for me?

[evilsim]

If I am right that YS is the blanking pin for the sony cxa2025as jungle chip, then it looks like I will have to step down the vcc from 9v to 3v since appears to be the max high for the ys blanking pin. Can someone else please double check the pinout for me?

From the datasheet it looks like yeah what you said - anything from 1v to 3v is 'high' for that YS pin. 9v is too much for that particular pin.

YS switch control input.
When YS is high, the RGB block signal is
selected; when YS is low, the Y/C block is
selected.
VILMAX = 0.4V
VIHMIN = 1.0V
VIHMAX = 3.0V

[takeshi385]

If I am right that YS is the blanking pin for the sony cxa2025as jungle chip, then it looks like I will have to step down the vcc from 9v to 3v since appears to be the max high for the ys blanking pin. Can someone else please double check the pinout for me?

From the datasheet it looks like yeah what you said - anything from 1v to 3v is 'high' for that YS pin. 9v is too much for that particular pin.

YS switch control input.
When YS is high, the RGB block signal is
selected; when YS is low, the Y/C block is
selected.
VILMAX = 0.4V
VIHMIN = 1.0V
VIHMAX = 3.0V

AWesome, thank you. I just got the tv today and haven't opened it up yet, but according to some documents online that should be it's jungle chip(tv repair man work log notes). I just ordered a power regulator so I can drop the 9v to 1.5v. It's a switching regulator which generally don't play very well with video signals in terms of interference, but hopefully since this is just a logic state pin this fact won't be an issue.

[Syntax]

If I am right that YS is the blanking pin for the sony cxa2025as jungle chip, then it looks like I will have to step down the vcc from 9v to 3v since appears to be the max high for the ys blanking pin. Can someone else please double check the pinout for me?

From the datasheet it looks like yeah what you said - anything from 1v to 3v is 'high' for that YS pin. 9v is too much for that particular pin.

YS switch control input.
When YS is high, the RGB block signal is
selected; when YS is low, the Y/C block is
selected.
VILMAX = 0.4V
VIHMIN = 1.0V
VIHMAX = 3.0V

AWesome, thank you. I just got the tv today and haven't opened it up yet, but according to some documents online that should be it's jungle chip(tv repair man work log notes). I just ordered a power regulator so I can drop the 9v to 1.5v. It's a switching regulator which generally don't play very well with video signals in terms of interference, but hopefully since this is just a logic state pin this fact won't be an issue.

You don't need a regulator lol.

If you wire a 10k pot or 2 resistors as dividers you'll turn 9v into whatever you want.

[Syntax]

Here's a link to a voltage divider calculator.
Once you understand its really easy to work out how to get the voltage you want

http://www.ohmslawcalculator.com/voltag ... calculator

If you have 9v and want 2.5 then you would wire 2 resistors and blanking like so

+9v-2.5k resistor-blanking pin- 960ohm resistor-Ground

You can change up the resistor values if you don't have those particular ones, just insert your starting voltage and output voltage into the calculator and a resistor value you have on hand and it will calculate the other resistor you need.

Should probably sticky this with blanking info.

[lolitsevan]

Hey, so I started messing with this mod on a sony kv20m42 like last year, and the project ended up getting back burnered. Just recently started messing with this again and I got pretty close, with a few issues. For the first 1-2 minutes the set is on, the picture is very purple. Black is kind of a vibrant dark violet, and the green almost looks black, blue and red are slightly tinted but I have a video that shows this better. After the set runs for a minute or 2, the color comes in perfectly, also this problem has never occurred when I have the tv set up to work normally over composite. I'm wondering if this is caps or the green IC, but I really have no clue. Discharging the flyback causes the color issue to come back, just turning the set off does not seem to reset it.

Some pictures of the color issue(sorry they're blurry, they're taken from the video I took explaining this)
Initial color(~first minute)


After warmup


However, the major issue is the picture scrolls up. Seems like a sync thing, but I don't know for certain. Check out the video below to see what I'm talking about.

Relevant(?) info: RGB and Blanking pins lifted, 75 ohm resistors inline on RGB lines from from console, then 75 ohm to ground, then .01 uf ceramic caps to output. Sync is fed to a composite input on the back, Ground comes from the jungle IC, 5v comes from a pin on the tuner.

Video with more information: https://www.youtube.com/watch?v=JYEhHM0lJK4

Any help would be greatly appreciated. I feel like I'm so close!

edit: figured it out, .01's were too weak, had to step up to .1 uf caps(104s) on rgb and sync lines. Right as rain now, my god does this look impressive. I think I might prefer the low tvl compared to PVM, looks a little more natural.

[evilsim]

I picked up a JVC AV-21LT3 - 2 blocks from my place today! It has a Panasonic NN5198K and a JVC MN1873287JL1 IC. I didn't have much of a shot but I've wired RGB to the Panasonic 6/7/8 pins and sync into the AV1 socket. YS pin 5 blanking appears to want GND to blank. Image is not stable. More when I have a chance. Some turkey had ripped the power cable out of the tv (probably when dragging it out of their garage), but that was easily fixed.

manual for this TV is here - https://drive.google.com/file/d/0B7_0Vi ... sp=sharing (page 36) im still unable to get an image or a stable image. also tried soldering RGB/YS onto the TEXT chip which is actually missing on my TV, no picture at all from that. bah im not having much luck.

[MarkOZLAD]

I picked up a JVC AV-21LT3 - 2 blocks from my place today! It has a Panasonic NN5198K and a JVC MN1873287JL1 IC. I didn't have much of a shot but I've wired RGB to the Panasonic 6/7/8 pins and sync into the AV1 socket. YS pin 5 blanking appears to want GND to blank. Image is not stable. More when I have a chance. Some turkey had ripped the power cable out of the tv (probably when dragging it out of their garage), but that was easily fixed.

manual for this TV is here - https://drive.google.com/file/d/0B7_0Vi ... sp=sharing (page 36) im still unable to get an image or a stable image. also tried soldering RGB/YS onto the TEXT chip which is actually missing on my TV, no picture at all from that. bah im not having much luck.

Hey evilsim,

Is chip IC371, the RGB switching chip, in place? I’m guessing if the set doesn’t have teletext then this chip won’t be there either and therefore the teletext lines won’t reach the Jungle. Is there an empty socket/unused port for IC371? Perhaps you can run the RGB to pins 15, 3 and 14. Might be a good idea to trace the path from those pins to the capacitors that are going into pins 6,7 and 8 of IC301, see if any jumpers etc are missing.

[lolitsevan]

So I'm still working on getting my RGB modded tv looking perfect, and the only issue I'm still having is some light colored vertical bars on very dark screens, mostly dark blue/purple backgrounds. The lines start brightest on the left side and progessively fade, becoming invisible around the center of the screen. It's most visible on the ff3 intro. Not sure if it's a voltage issue? Sorry for the crappy pictures.

Wiring is:
RGB - 75 ohm inline, 75 ohm to ground, .1 uf cap to jungle
Sync is unaltered, the .1 uf cap inline doesn't seem to make a difference, so I took it out.
5v from pin 3 on the tuner.
Ground from the jungle ic.

Album of pictures of the issue - https://imgur.com/a/EVmVQ

I've tried 3 different snes, 1 modded mini with rgb from the encoder, 1 modded mini with the ths 7374, and a 1-chip 01, all with basically identical vertical line issues.

Any insight is appreciated, it's not really a big issue since it's only visible on a few screens that I've seen so far but I just want to make sure this isn't a sign of a more sinister problem.

[Syntax]

Make another ground to somewhere on the chassis near the audio input. Could help.

Ensure the sync line has a 75 ohm termination. Try another cvbs channel?

Try another SNES PSU if you can, but probably not it..

Sometimes with too much voltage blanking can do odd things, may pay to wire it to a pot and give it a twist.

[lolitsevan]

Make another ground to somewhere on the chassis near the audio input. Could help.

Ensure the sync line has a 75 ohm termination. Try another cvbs channel?

Try another SNES PSU if you can, but probably not it..

Sometimes with too much voltage blanking can do odd things, may pay to wire it to a pot and give it a twist.

Thanks for the advice, when you say make another ground do you mean split the ground coming from the console and then ground the extra line somewhere around rear audio? Sorry I'm not very familiar with general electrical stuff. I've got pots coming later this week and I'll try wiring one of those up to mess with blanking voltage. Different psu made no difference, same with 75 ohm inline on sync vs no resistance, same result. I tried both composite inputs from the jungle ic and they only seemed to add noise to the picture, I might try the front cvbs jack but I'm not sure it'll make a difference for this. It seems like interference or something based on proximity to my socket or switch, when I have the set totally open working on it the problem isn't nearly as bad as when I close it up and the components are close to the mainboard, when I slide the back of the set where my components are mounted toward the tube you can see the jailbars get brighter. I don't want to have to rewire everything but I think starting from scratch being more conscious of my cabling might be the best way to go.

[Syntax]

If you run an unshielded sync wire anywhere near power it will cause really bad interference.

Yeah grounding to just 1 ic leg is a bit weak, best to run at least 2 grounds, one for video one for audio.
Split from the console ECT.

[evilsim]

lolitsevan I have had problems like that when using a cheap non genuine power supply for various consoles. If you are using an aftermarket PSU for your console try and different one, or if its available, try a different RGB TV and see if it does the same thing there. Might not be your RGB modified telly...

[evilsim]

MarkOZLAD thanks, Ive tapped those pins u suggested and there are no missing jumpers on this mainboard. Doing this gives me a nice bright RGB image, which is not stable at all. I cannot seem to locate the sync on this JVC. This is the 3rd tv in a row ive been unable to get sync on... tested continuity on my wiring from the Famicom console to the AV port and other locations, still no synced picture. This TV has a Panasonic tube so I am even more keen to see it working, based on other peoples comments on Panasonic CRT images. Tried clean sync, composite sync, even tried soldering direct onto the various IC's H/V sync pins from the output of a lm1881 stripper.. still no stable picture.

[MarkOZLAD]

MarkOZLAD thanks, Ive tapped those pins u suggested and there are no missing jumpers on this mainboard. Doing this gives me a nice bright RGB image, which is not stable at all. I cannot seem to locate the sync on this JVC. This is the 3rd tv in a row ive been unable to get sync on... tested continuity on my wiring from the Famicom console to the AV port and other locations, still no synced picture. This TV has a Panasonic tube so I am even more keen to see it working, based on other peoples comments on Panasonic CRT images. Tried clean sync, composite sync, even tried soldering direct onto the various IC's H/V sync pins from the output of a lm1881 stripper.. still no stable picture.

Really strange mate. Sync is something I rarely have issues with, normally just extract Scart Pin 20 and 17 to an RCA cable and into an AV port. Can you describe more clearly how you are getting sync? Does the famicom have a composite output that you can try plugging into an AV port?

Any chance posting some photos of your setup?

Folks here happy to help anyone who has a red hot go and you obviously are.

Note: I did notice last night that one of my scart cables won't sync, I haven't investigated why yet but I assume it is because it has the sync ground connected to the wrong place. it's a scart cable that cost $95 new (I got it second hand)

[kortina]

I am not very experienced with electronics, and would like to try a RGB mod on an old TV that I am about to get.
I have read over lots of this thread, along with the info from 133fsb and ScartHunter. I am keen to show that I have put some thought into this mod, and would like someone with more experience to let me know if I am on the right track.


I am about to pickup a NEC fs-59v81s it appears to be a generic CP-785A chassis that is used in Daewoo too.
Service Manual:
https://elektrotanya.com/daewoo_nec_dte ... nload.html
https://drive.google.com/file/d/0B_A2VG ... sp=sharing

More detailed manual for the CP-785A Chassis:
https://drive.google.com/file/d/0B_A2VG ... sp=sharing
https://elektrotanya.com/daewoo_chassis ... nload.html

Very strange that this TV has a SCART connection, however the RGB pins (7,11,15) are not connected!?
I assume this means that I can only input Composite over SCART by default.


From the second manual there is a very interesting section.

Fast R, G, B insertion : The external R, G, B insertion needs a fast switching and cannot be controlled
by the software ( instruction cycle of 1m sec ). The fast switching pin 16 of SCART 1 is directly
connected to the TV processor pin 45 ( Fast blanking input ). The display is synchronised with the
selected video source, i.e. to get stable R, G, B inserted signal they must be synchronised with the
selected video source. The controlling software only enable or disable ( AV2, SVHS, or Forced RF
source selected ) fast blanking.

The Jungle IC is TDA935x /6x /8x

So I *think* the Mod should be simple with:
Connect the unpopulated SCART-PIN 15 (Red) to Pin 46: - R2IN 2nd R input (with 75Ohm and 0.1uf cap)
Connect the unpopulated SCART-PIN 11 (Green) to Pin 47: G2IN 2nd G input (with 75Ohm and 0.1uf cap)
Connect the unpopulated SCART-PIN 7 (Blue) to Pin 48: B2IN 2nd B input (with 75Ohm and 0.1uf cap)

Connect SCART-PIN 16 to Pin 45

As SCART-PIN 20 is already connected, then the sync should already connect correctly?

It would be most appreciated if someone with a bit more experience could review my guess.
Pictures and results will be posted.

[MarkOZLAD]

I am not very experienced with electronics, and would like to try a RGB mod on an old TV that I am about to get.
I have read over lots of this thread, along with the info from 133fsb and ScartHunter. I am keen to show that I have put some thought into this mod, and would like someone with more experience to let me know if I am on the right track.


I am about to pickup a NEC fs-59v81s it appears to be a generic CP-785A chassis that is used in Daewoo too.
Service Manual:
https://elektrotanya.com/daewoo_nec_dte ... nload.html
https://drive.google.com/file/d/0B_A2VG ... sp=sharing

More detailed manual for the CP-785A Chassis:
https://drive.google.com/file/d/0B_A2VG ... sp=sharing
https://elektrotanya.com/daewoo_chassis ... nload.html

Very strange that this TV has a SCART connection, however the RGB pins (7,11,15) are not connected!?
I assume this means that I can only input Composite over SCART by default.


From the second manual there is a very interesting section.

Fast R, G, B insertion : The external R, G, B insertion needs a fast switching and cannot be controlled
by the software ( instruction cycle of 1m sec ). The fast switching pin 16 of SCART 1 is directly
connected to the TV processor pin 45 ( Fast blanking input ). The display is synchronised with the
selected video source, i.e. to get stable R, G, B inserted signal they must be synchronised with the
selected video source. The controlling software only enable or disable ( AV2, SVHS, or Forced RF
source selected ) fast blanking.

The Jungle IC is TDA935x /6x /8x

So I *think* the Mod should be simple with:
Connect the unpopulated SCART-PIN 15 (Red) to Pin 46: - R2IN 2nd R input (with 75Ohm and 0.1uf cap)
Connect the unpopulated SCART-PIN 11 (Green) to Pin 47: G2IN 2nd G input (with 75Ohm and 0.1uf cap)
Connect the unpopulated SCART-PIN 7 (Blue) to Pin 48: B2IN 2nd B input (with 75Ohm and 0.1uf cap)

Connect SCART-PIN 16 to Pin 45

As SCART-PIN 20 is already connected, then the sync should already connect correctly?

It would be most appreciated if someone with a bit more experience could review my guess.
Pictures and results will be posted.

Your theory looks sound except that there already appears to be caps on the board. Should be able to use them. Try pulling the leg of the capacitors farthest from the jungle and connecting your lines to them. On one revision of the board they are attached straight to ground, on the other I'm not sure, looks like maybe empty jumpers you can connect to. Depending on which revision of the board you have will determine your exact mod.

EDIT: I noticed the caps on one of the board revisions are going straight to ground. On the other they don't appear to be. Either way I believe these caps can be used.

[evilsim]

I really appreciate all the help. I got the darn JVC TV going. During my testing, I was switching the input from TV to AV1, but infact I was stuck on TV channels the whole time . I had to go into the menu, select input AV and then I'm on AV and wallah. The JVC works with composite sync and Y-sync but not clean sync. I know its an RGB picture because when I test it with my SuperFami which I YUV modded, I use the Y as sync (along with connecting the factory RGB lines from the multiout) I then get a black and white picture. As soon as I enable blanking, full colour rich RGB image!

I ended up going with your IC371 pins 15, 4 and 14 (could have used Jungle IC EXT RGB pins but your route includes caps) and obviously composite sync goes to the AV1 ports. I used the EXT-YS line on the Jungle and pulled it high (basically anything above 0v and it blanks).

Next ; back onto the NEC or Sony tv(s) I have. Hopefully no more silly mistakes

I also never discharge the TV's, should I be doing this ? I'm very careful when working on these things.