shmups.system11.org

I was trying to tap in to the L/R audio inputs on the video one bank (underside of the board) where I'm using sync and ground to the s-video port. I was using an RCA Cable plugged in with the bare center wire of said RCA cable attached to one lead of the multi meter to try to see which contact point was the white and red RCA audio ports. but when doing this it seemed as if three points were toning out regardless of which port I was plugged in to.

As of right now I have audio but it is extremely low. part of my mistake was more than likely thinking I could use a common ground between both the video and audio. it is grounded that way on the scart connector I put in (2, 5, 9, 13, 17 all going to the s-video ground pin). Or I may be feeding both channels in to the same channel...

I do however use this s-video port form my extron MPS 112 for any consoles that are only capable of s-video. So currently (though whilst nothing using s-video is on) there is a lead form the switcher plugged in to this video and audio ports under normal operation. I plan to grab a pic of the underside where I'm trying to tap in since I was doing things the hard way and not detaching the board completely form the system (so I was upside down on an ottoman while doing this lol). Yes I did discharge the tube and stayed away form most of the high voltage circuit in case the caps were not fully discharged. As with many things this short project started to annoy my fiancee which of course put me in to a bit of a bad mood lol.

While I'm not incredibly versed in working on CRTs it is something I do have very minor experience on, with a combination of years of dabbling in electronics (and a short time working in an arcade). I originally started in 1995 in the Army as a 25R which is audio video information repair, or a glorified TV tech.... but didn't really use any of that for a very long time until I began working at a TV Station 15 years ago...but by that time analog was on the way out and we became a disposable society of sorts and no one really worked on this type of stuff much. Part of me and my love for all things video game related felt this was a dying art and it made me sad to see so many CRTs being discarded lol. sorry for the lengthy post but figured I'd at least give a baseline of my knowledge on this stuff...there is so much to learn and I'm late to the party but we have to start somewhere.

well soab.... i was chasing my own ghost.

guess I partly told what was wrong in the previous description...I guess having the audio tapped in from the scart AND having RCA lines plugged in from my MPS112 couldn't happen... as soon as I unplugged them the scart audio normalized. as soon as I plugged the RCA plugs back in...audio shot waaaay down in level (oddly even on the OSSC Side of the gscartsw).

I thought I could have them plugged in as long as both weren't active at the same time...or am I still soldering to the wrong points lmao

Ok, so I redid things and made them permanent. I decided to use the front i/o board to tap in to for sync, ground and audio. In addition I mounted the blanking switch on the front of the TV in the i/o & button panel section. I posted up some pics... I should have gotten better but honestly DRC has the pics up of this set and where he tapped in the wires.

https://imgur.com/a/BBdqLEB

Next issues to take care of:

Something in my chain is causing RF interference. Oddly if I unhook the OSSC it mostly goes away. If I unhook all the other AV cables in the back it seems to amplify the interference when the ossc is plugged in. This happened with my older OSSC as well so something somewhere is picking up this interference. The vast majority of cables I have are overkill and shielded...but one could be slightly touching the shielding and or a bad cable.

I'll add the other info as I can and get the pics uploaded. I want to try to catch a few things and get your opinions.

Ok here is one of the issues I was speaking of... did I wire the blanking switch backwards or was my resistor possibly bad (I used a 2.2kOhm)?

When blanking is on the screen has a ghost to it, when it is off... it doesn't.

https://imgur.com/a/TGt79zZ

Oddly enough the switch was flaky after replacing my issue went away! I noticed after I took everything back apart to see what I could move around and route differently and shield better... when jiggling the switch around the sync kept going in and out until it just stopped all together. just goes to show, sometimes the simplest answer is the correct one.

I have to hold off on my modding of my KV-27S42 as I wait for a Retro Access cable to come in (hopefully this one if I make it tomorrow) but until it does I have a few questions.

First off, both of my RGB modded consoles output csync so I should be fine wiring sync to go through composite video instead of the luma on the s-video, right?

The second question is about the blanking set-up:
Now I am planning to use a BNC input instead of a SCART input so because there is no SCART/pin 8 to pull the 5v from, I can just pull any 5v from the tv board or is there one that would be recommended?

Csync can go through AV or SVideo luma. The SVideo luma has been used because people have reported that it reduces or eliminates the “left shift”.

On the diagram I give two options for 5V, EEPROM leg 8 or 5V regulator output. There are likely many other places you can grab it from

Ok so that says EEPROM then. When I first read it, I wasn't sure what it said so when I say leg 8, I thought you were referring to the SCART pin 8 which has a 5v signal:

It's in fact normally a 12V signal from pin 8 (9-12V for 4:3, 5-8V for 16:9), it's only 5V from Super Nintendo because it doesn't output 12V.

I recommend everyone read the Wikipedia article on Scart, it's such a handy document.

So I'm trying to mod the 38 inches KV310 from Brazil.

The jungle is a CXA2155s and the microcontroller is M306V5ME-121SP.
I'm very familiar with this mod and this 38 inches is almost identical.

I have it's service manual that doesn't help at all, it is copy of the 29 inches model with the wrong jungle and microcontroller.

I'm doing a complete no cut mod, I have sacrificed VIDEO 5 removing any connections of it and using as R G B input.
Removed the S-video connector in the front and put the switch there.
It's beautiful I've also recaped the entire A board.

Now I'm pretty sure the pinout of those jungle and micro controller are different.

Did my mod as the same for the 29 inches.
Removed the resistors from R G B out of the micro controller removed the caps from R G B in from the jungle IC. This should in theory isolate those pins. And I've used the same resistors microcontroller -> 5.6k -> diode -> MUX
External 75 ohms to GND -> 1k -> MUX -> 104 0.01 50v ceramic caps -> jungle.

Now I say that I believe the pintout is different because
1. Diode D008 does nothing for blanking.
2. I can see R and G when pressing the menu key but I can't see blue.
3. Blue is the only color from the menu that is present.

So if anyone modded the US version of this TV KV36 310 and tell what pins R G B in are on the jungle this would be really appreciated.

It appears there are no pinouts for CXA2155s online....

Your known point is the microcontroller. Trace it's RGB (28,29,30) and O_YS (20) circuits using photos/multimeter until they reach the Jungle.

This service manual seems to suggest that the CXA2155 is pin compatible with the CXA2154.

host images online free



Done. No cut mod.

The pinout is the same, my mistake.
The only thing is that I've tried soldering to D008 it's no good.
Using a 2k2 resistor but soldered to L304 and blanking works

I did just like last time. Isolate RGB out and RGB in pins. Isolat the video 5 Y Cb Cr pins amd use as an entry point for rgb.
There's gnd nearby just solder 3 75 ohms together and one leg to GND and the 3 to the Y Cb Cr pins.

I've also recapped the entire A board, geometry and convergence are spot on. Really nice to see this kind of perfection on such a huge tube.

Forgot to add a pic with menu muxed:

Looks a winner.




That's the money shot.

not sure how I feel about sacrificing a YPbPr input for RGB... especially when the audio input isn't even utilized

I tend to agree.

I use RCA these days too. I do it like this:

That looks good Mark,nice and simple.

If I do find another tv to mod I will go this route and also hack a 360 component cable with a female scart on the other end.

When you use RCA jacks like this, do you use a 'game console' to SCART cable and then a SCART to RCA adapter? Or do you make your own, or does someone else make a 'game console' to RGB RCA cable? Are you using the sync over the composite or s-video input? (sorry for all the questions, brand new to this and trying to learn before I try my first mod )

I build these...





Inexpensive but very effective.

“20 Pin SCART Male to 3 RCA Female S-Video Audio Video Adapter Cable Connector SCART Plug to 3RCA Jack S Video AV TV Converter” - should cost less than $3 USD.

I’ve also built a more fancy one....



Then I learned about the Otaku switches that have RGB over RCA.

https://otaku-games.com/misc/6-port-rgb ... using.html

Awesome! Thanks!
Do you make your own SCART cables for your game systems as well? I saw this diagram for the SNES. (is that yellow square a 180 Ohm resistor? Is the composite video line the Csync?)



Or is it better to just buy them? I don't know much about impedance matching, and I saw that mentioned on some higher end cables. I also saw a 330Ohm resistor for the Csync line mentioned on a high end cable for sale, but that's not in the diagram above. Is that optional?

edit: Sorry for the delayed reply. I was waiting on my initial post to be approved.

I don't like wiring scart, so no.



Yes. It acts as a part of a voltage divider with a 75 ohm resistor that is in the TV set to drop 5V down to 1.5V for RGB Fast Switching/blanking (on factory scart sets anyway)



Yes. Scart standard is Composite Video as Sync. We inject csync or luma because its either what we have or because we might get cleaner images.



Completely up to you. I buy them.



This would depend on the console. That seems like it would be attenuating 5Vp-p sync to 1Vp-p suitable for a TV. 5Vp-p is also know as TTL sync - Transistor to Transistor Logic levels are 5Vp-p. TV's want less than 1Vp-p (usually 0.3Vp-p) sync so needs resistors. Once again the resistor works with a 75 Ohm resistor in the TV to make a voltage divider.

Thanks!

Just finished this mod for my KV-32FS100 and wanted to thank you for your work developing this walkthrough. Got a few geometry issues to correct, but the picture looks absolutely fantastic now, and your write up made it so simple to install!



Also wanted to let you know 680's are indeed a suitable replacement (I didn't have 750's on hand, I could have chained some smaller ones together but figured hey, just try it and see what happens)

Thanks again!

Great, another one saved from the dreaded OSD Snip!

Feel free to post some photos, especially with the OSD showing...

Soo... the funny thing is, I actually found this thread while modding my TV the old fashioned way... I was half way through using some sketchy diagrams someone posted in the big RGB mod thread (you know the one... that 90-something page thread), and was looking for a better guide while taking a break and came across this thread. So now I've got a big 4PDT switch controlling the one 5V blanking line...





Pictures really don't do justice to how sharp the picture is

I also 3D printed a little bracket for my SCART connector so I could rear-mount it without having to leave excessively long leads to get the TV case on/off. It screws to the back case for strain relief (same as the TV's built-in inputs), but it's glued to the 3d printed piece which clips onto existing holes in the bottom of the TV's frame, so the whole assembly stays in place when you take the shell off (not that I plan to do this often, but any excuse to 3D print something is a good one ;D

I don't care for the SCART connector, but I must say that's well done

You can use the through-hole pads on TU150 if your TV doesn't have a 2nd tuner.

Very inventive.

Thanks! Any particular reason against the SCART? Or a suggestion as to an alternative? I'm primarily a Genesis/MD collector/player, and the Genesis/SCART cable seemed to be the most common choice for RGB setups