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Adding RGB input to an old CRT TV

Derick2k said:
Awesome, would Tvs with component inputs also work?

I am picking up a KV27S66 tomorrow and a KV-35S42 on Sat. One is free and the other $15.

What parts do you recommend we get? Switches/Caps/Resistors, etc...
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Meh, with the component sets. You're just as well off to get a decent transcoder to convert YUV.


KV-35S42, you say?

Well..

w2OzXY8.png


MuUSROK.png


2ywdb2q.jpg


There's ya a nice KV-35S42.

Get the following:

RGB female connector of your choice. (I use SCART as it's a standard)

4PDT switch - To switch the OSD RGB lines with your own RGB Source + Blanking

75 ohm resistors. - To match impedence of the 75 ohm signal load
.1uf capacitors. - For DC voltage offset, and black level restoration.


Do the following:

Lift pins 16, 17, and 18 of the Jungle I/C. Terminate your RGB inputs with 75 ohm resistors to ground, and then with a .1uf cap to the RGB inputs. Like so:

35cizvl.jpg


Tie a low voltage source (5v) to pin 15. This will enable RGB output. When you hold the pin high with that 5v source, it's game time. When it's low, your TV will operate normally.

Enjoy life.

Here's an excerpt from the Jungle I/C Datasheet for that particular set (35" Trinitron you speak of) I've outlined the most relevant information for you.

6sB9T2S.png


EDIT:

I just want to say something here.. This is a forum dedicated primarily to arcade stuff. Please keep in mind. A lot of sets have "free running" synchronization. Meaning, a lot of televisions will scan between 50Hz and 60Hz.

However, not all televisions do. Several are genlocked, including a lot of Trinitrons. You may have just a few Hz to play with. Ie: 58-62Hz.

Arcade boards are interesting in what their native scanning rate is. Some scan at wonky frequences (like 56 or 57Hz). This may yield some compatibility issues with a few arcade PCB's. Just wanted to throw that out there.
 
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You sir are awesome!!! :thumbsup:

Quick question, how is audio handled using this connection?

Did you internally wire audio from the scart connector to TV mainboard?

I am sure I will have more questions for you once I get all needed.

Thank you for all your help on this.
 
Voultar, Is the switch simply to supply 5V to pin 5 for RGB operation and cut 5V for standard operation?
 
Voultar said:
EDIT:

I just want to say something here.. This is a forum dedicated primarily to arcade stuff. Please keep in mind. A lot of sets have "free running" synchronization. Meaning, a lot of televisions will scan between 50Hz and 60Hz.

However, not all televisions do. Several are genlocked, including a lot of Trinitrons. You may have just a few Hz to play with. Ie: 58-62Hz.

Arcade boards are interesting in what their native scanning rate is. Some scan at wonky frequences (like 56 or 57Hz). This may yield some compatibility issues with a few arcade PCB's. Just wanted to throw that out there.
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I mainly want this for retro gaming on my consoles since they are all RGB modded, I currently use them with an XRGB mini, which is great, but having a nice 35" CRT instead would be amazing. Considering I was willing to spend $300-500 for a 19"-20" PVM, this is a no brainer.

So for arcade purposes, we would just have to identify which tvs have "free running" synchronization? Maybe we can make up a list identifying models that would work for arcade purposes as well.
 
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Derick2k said:
Voultar said:
EDIT:

I just want to say something here.. This is a forum dedicated primarily to arcade stuff. Please keep in mind. A lot of sets have "free running" synchronization. Meaning, a lot of televisions will scan between 50Hz and 60Hz.

However, not all televisions do. Several are genlocked, including a lot of Trinitrons. You may have just a few Hz to play with. Ie: 58-62Hz.

Arcade boards are interesting in what their native scanning rate is. Some scan at wonky frequences (like 56 or 57Hz). This may yield some compatibility issues with a few arcade PCB's. Just wanted to throw that out there.
Click to expand...
I mainly want this for retro gaming on my consoles since they are all RGB modded, I currently use them with an XRGB mini, which is great, but having a nice 35" CRT instead would be amazing. Considering I was willing to spend $300-500 for a 19"-20" PVM, this is a no brainer.
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Then follow my little guide above, and you certainly won't be disappointed. It may not have the high line count or convergence options of a BVM. But it has a solid screen and excellent aperture grill picture quality.
 
Also found a JVC AV-32S33 32" that might be a good candidate for this mod, seems like you could tie into the rgb for the PIP. I will try to post the schematic when I have a chance.

So here is the schematic AV-32S33

I am not 100% sure on this, but maybe the PIP ic that has its RGB inputs grounded could be used to inject our RGB source there and take over what the PIP would have displayed?
 
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I ordered the parts needed and should be picking up the KV-35S42 this weekend.
 
Mitsurugi-w said:
Voultar, Is the switch simply to supply 5V to pin 5 for RGB operation and cut 5V for standard operation?
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The switch is a mechanical means to not only switch your low voltage for RGB blanking, but also to switch between your RGB source and the OSD's RGB.
Leaving the OSD RGB inputs in circuit can create some coupling/noise in the picture. It's best to isolate those. You can of course use a multiplexer or something else to switch these all around. A 4PDT switch is just the easiest.

You can also simply use the 5v source from your console/system to hold the YS/blanking pin high. But for the sake of compatibility, I find it best to use a switch. Not everything outputs 5v, ya know. :D
Derick2k said:
You sir are awesome!!! :thumbsup:

Quick question, how is audio handled using this connection?

Did you internally wire audio from the scart connector to TV mainboard?

I am sure I will have more questions for you once I get all needed.

Thank you for all your help on this.
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If you're using a female SCART connector. Simply tap into one of the composite inputs and attach that to pin 20 of your SCART connector. You'll be using the composite as your Sync Source.

TV's have fairly sophisticated sync cleaning/separation circuitry. Regardless if you feed it luma, composite video or c-sync, it will work just fine.

Much like you'll be using the composite video input for your sync source, you'll also be using stereo left and right audio from the same set of inputs. Simply tap them from the board/RCA jacks and wire them accordingly.
 
Thanks Voultar,

I am picking up the TV tomorrow and I have the parts/female scart connector on hand.

I will post questions/results once I get into it.
 
Oh my god, a 35" RGB Trinitron would be incredible. Very cool work here.

When you get it up and running, I'd love to see some high-res pictures and videos of how it looks.
 
Derick2k said:
So I finally got this 35" monster home. No easy task, I had forgotten how bulky and heavy they are. Picture looked good, but it will probably need some tweaking before I start hacking into it for RGB.

File_000.jpeg
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Dont worry about adjusting geometry or colors yet, you will have to do it all again once its RGB modded.
 
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