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HDMI to Old CRT
Zebidee:
--- Quote from: abstract3000 on November 20, 2023, 12:45:27 am ---1st issue. I am convinced something is up with the EDID Emulation when sending the signal through, what you are calling the offset is identical on the monitor and the TV, what has me convinced of this is with the new Chinese adapter I got today I hooked that up to the Panasonic ran the signal through and it displays just fine but the image is offset identical on that one as to the monitor and the other CRT and even more to a degree. Why do I believe this offset is an issue? Well in the first images I showed early on getting the signal through the TV displayed the entire image of the desktop with the Task bar fully visible. So I'm guess with all my playing around with Arcade OSD and CRT_Emulator I messed something up. I get that the EDID emulation isn't the "important" part but you don't get a signal unless its turned on.
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Errr...., "offset" is your term, the only time I've used the word here was regarding PCB offset feet which are used to physically screw down a GreenAntz unit.
As you've discovered, EDID emulation either works or it doesn't. It has nothing to do with your overscan issues. If it ain't broke leave it alone. I recall someone saying somewhere that every time you click EDID emulation on/off, you should re-generate and re-install the video modes. So keep that in mind.
--- Quote ---2nd issue is with colors, maybe you might have an idea what it means, I discovered today with the SHARP that the Green shows sometimes for some things but is missing in allot of other things and I almost believe if this issue is fixed that would be the end of most everything
In your expert opinion what does that mean? Or What would be the root cause of that?
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Yeah, your Sharp TV definitely lacks green, though not completely. Seems to be absent entirely at lower levels. However it seems to be present if the signal is strong enough. Which is why I think about RGB (green) cutoffs (not offsets, presets or porches...).
Does the Sharp TV lack green with other inputs? If so, maybe there is an issue with the green drive circuit or the cathode in the tube itself.
Another possibility is that with S-video (& YPbPr), the Y signal carries both sync and luma. Luma mostly concerns brightness, but is also important for determining green in particular. If you are putting sync in via composite/AV input, and there is no resistor on it, then it could possibly be swamping the green.
To explain... sync signal is simply "ON" most of the time. Sync pulse is triggered by low-active state, a lack of voltage. Sync is carried on the Y (luma), which also includes picture information. By running the sync in from VGA at 5v, you're essentially blasting luma at more than max into the TV, through an AV input designed for 1v max. Of that, the actual sync part of that signal is only meant to be 0.3v max.
This is why I go on about the resistor on sync. This is really the bare minimum.
(If it was me, I'd also use a Schottky diode (IN58XX, reverse biased, cathode to signal, anode to GND) to CLAMP the sync to GND. A second schottky diode, in the opposite to orientation (forward biased), would then limit the sync to approximately 0.3v max. This is CLAMPING, it just keeps sync within normal range and makes it easier to for the TV to work out which is what. I've harped on about this more than I've wanted to. Please show me more pics!)
Anyways, the jungle blanks AV input (except the sync) when the OSD is active (that's why they call it a "blanking" signal), so I'm entertaining a hypothesis that the jungle is blanking a field of green, and that somehow means you have little green for your RGB OSD mod. Easiest way to test this theory would be to disconnect the blanking voltage and see what kind of image you get - if you see a bright screen, either white or greenish, then that could be the problem.
Another cause could include the Ultimarc amp (if it isn't boosting green as much), but this seems unlikely.
--- Quote ---You mentioned to go checkout the RGB cuttoffs, I got the service manual and studied it a bit, and found out how to get into the service menu. Here in the service menu I have these particular options:
I highlighted the most obvious, but which one of those would be the cutoffs?
--- End quote ---
You'll have to experiment for yourself. Every TV is different, and each manufacturer seems to use different terms, so I can't be certain. All I could really do is make educated guesses.
XXX_BIAS are likely equivalent to "gain", concerning colour brightness. XXX_DRIVE might be colour intensity, but it also might concern the cutoffs (minimums) I mentioned. Sometimes I see the cutoffs listed as "RC", "BC", "GC".
You should also look out at settings like "YC", which probably concerns a balance between Y (luma, brightness & sync) and C (chroma, colour).
H_BLK_R and H_BLK_L may be for tweaking the horizontal position.
BS_START and BS_GAIN sound like they could be worth adjusting, but I'm not sure what they might be for.
I wonder what R/B_ANGLE is about, whether it concerns the colour mix.
Leave settings like TINT, CONTRAST, COLOR, BRIGHTNESS at neutral settings, at least until you've bedded down your setup a bit.
SHARPNESS should be set to zero (00) or a neutral setting. Go with 00. It is for making crap TV or VCR signals look less crap - doesn't do anything useful for RGB or component inputs.
You may have other pages of service mode adjustments - my China TV has 20 pages! Most are not accessible without entering more service mode codes.
abstract3000:
ok so this is going to be a headscratcher, i have spent a bit more time with the TV and this is the info I have gathered
Let's start off with the Resistor on Synch. It is there and always has been, i looked at the schematic posted earlier and it is on there, I used my multimeter verified this and the fact it is a 1K resistor.
I have reposted the Schematic below, this is the current setup except for the decoupling Caps that were removed.
Here is a Picture of the modification going to the TV
This is the Ultimarc Board connecting to a project board, the more important thing to note is that there is a trim pot on that board connected to the blanking, that will make more sense as I continue on with my observations.
So i found a Panasonic 3DO laying around that had an S-Video Output, I connected it to the TV swapped the Input and everything looks great colors wise, nothing seems to be out of place. I managed to snap this photo that depicted several shades of green all appearing correctly.
Now lets move back to the RGB Mod and discuss the Blanking.
You See how the Picture looks fine? Well I can't just switch from the RGB to S-Video and have a picture with great colors, I have to adjust that trim pot all the way to the other side to get S-Video to show up. Now lets Say S-Video is to the Right, and RGB is to the left (don't thing about that too much i might have it backwards) Anyways in the middle sits is a black screen and distorted graphics and what I believe is called the OSD (On screen display?) It's the text that appears on the screen when you change a channel, or hit the menu button. (Don't shoot me if I'm wrong) Well there is a sweet spot you can get to where you can see that text just barely visible unless over light colors it will be black.
This is what Paperboy looks like when the Blanking has been adjusted to where I will be able to see the menu
Now here is a photo of the menu pulled up and here is the funny thing, look at the letters themselves; they are the accurate colors of what's supposed to be displayed below them on the Screen?!?!?!
So that's where I'm at, I also tried to get into the service menu but at this point i feel it's a lost cause, So the only way I can get into the service menu is by adjusting the blanking as seen in the previous photos, then putting into regular channel mode (no RGB or SVIDEO) the menu refuses to come up in either of those 2 inputs. Then when I get it up it looks like this:
I mean I can really struggle through changing a value if needed, but when I change the value I have absolutely nothing but static to see what impact said change even made so I left it alone.
Zebidee:
I'm guessing that there is a problem with the blanking voltage. When you use the OSD it overlays the image, showing correct colors, because the OSD is sending the right blanking voltage.
See that 75R resistor (termination) on the blanking line? Try lifting a leg to remove it from circuit, see how it goes then. That resistor might be pulling the blanking voltage too low, and I'm not sure it is needed.
EDIT: Attached schematic
abstract3000:
--- Quote from: Zebidee on November 23, 2023, 04:33:33 am ---I'm guessing that there is a problem with the blanking voltage. When you use the OSD it overlays the image, showing correct colors, because the OSD is sending the right blanking voltage.
See that 75R resistor (termination) on the blanking line? Try lifting a leg to remove it from circuit, see how it goes then. That resistor might be pulling the blanking voltage too low, and I'm not sure it is needed.
EDIT: Attached schematic
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You might be correct in your assumptions that the 75 Ohm Resistor is not needed, I pulled the leg from Ground and the Signal Still comes through to the TV, though my observations are as follows,
The colors are still off in some sort of fashion, The OSD menu is still damn near impossible to see, so I had to push the resistor end back to ground to see and play with the menu. I found the "Favorite Color" option is the only Picture Setting that had any noticeable effect on the picture, Contrast brightness etc. all the way up or all the way down made no visible difference. Though again when i touched the resistor to ground the screen went Black & white as pictured above where I have to set the Blanking pot to see it. Though disconnected the pot no longer works and the screen is visible.
So I'm not an electronics Expert far from actually, but hear me out. That Trim Pot that's installed grounds out to a 75 Ohm resistor so Ground Terminal -> Resistor -> Ground. My understanding is everything has to have a current and a Ground, so when I pulled up the leg, we left the Pot there without a ground rendering it useless. So what if we just take the Trim Pot Ground terminal straight to Ground bypassing the resistor all together? Then I assume the trim pot would work again with the blanking. though it might just put us back in the same boat. Scratch that, Just tried that And all I get is a Black screen as seen in previous photos, and adjust too far it turns the TV off, and nothing useful. Though without the ability to adjust the blanking Signal it should be noted that I no longer have the ability to use the S-Video Input.
I also might just be thinking about this in a very stupid fashion, and you can slap some sense into me if that's the case but man I tell you those Whites are Bright!!!! Like "OverPowering" Bright, like it might be so damn bright its overriding the darker colors... The Ultimarc Board is what's feeding the power through, wondering if there is a way to "Adjust" the amount of voltage it's feeding to try and potentially bring it down :/ though what I'm thinking might be way off...
So it appears Grey is the Magic color (Adam Duritz would be so proud)
I'm going to study the manual a bit more and test this menu options out but i have it available to begin adjusting and can see it :)
As for the Color Issues, I grabbed the Paperboy rom and loaded it up again and here we are in the same place :/ though the windows menus and Icons are easier to read...
I also noticed this is a very strange color difference on Bubble bobble, so I can't really say where the issue is with what color....
Zebidee:
--- Quote from: abstract3000 on November 25, 2023, 05:34:08 pm ---You might be correct in your assumptions that the 75 Ohm Resistor is not needed, I pulled the leg from Ground and the Signal Still comes through to the TV, though my observations are as follows,
...
So I'm not an electronics Expert far from actually, but hear me out. That Trim Pot that's installed grounds out to a 75 Ohm resistor so Ground Terminal -> Resistor -> Ground. My understanding is everything has to have a current and a Ground, so when I pulled up the leg, we left the Pot there without a ground rendering it useless. So what if we just take the Trim Pot Ground terminal straight to Ground bypassing the resistor all together? Then I assume the trim pot would work again with the blanking. though it might just put us back in the same boat. Scratch that, Just tried that And all I get is a Black screen as seen in previous photos, and adjust too far it turns the TV off, and nothing useful. Though without the ability to adjust the blanking Signal it should be noted that I no longer have the ability to use the S-Video Input.
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The pot has three legs, but looks like you are only using two. Connect the third leg, through that 75R resistor, to GND (may be easier to just use a new resistor). This should give you proper control over the blanking voltage level.
I've re-drawn the schematic and attached it below. The 75R should be attached to the "wiper", not to the output.
--- Quote ---I also might just be thinking about this in a very stupid fashion, and you can slap some sense into me if that's the case but man I tell you those Whites are Bright!!!! Like "OverPowering" Bright, like it might be so damn bright its overriding the darker colors... The Ultimarc Board is what's feeding the power through, wondering if there is a way to "Adjust" the amount of voltage it's feeding to try and potentially bring it down :/ though what I'm thinking might be way off...
--- End quote ---
Once you get this mod's blanking sorted out, if that ever happens, maybe try it without the video amp.
Otherwise, it is easy enough to make a gang of three RGB pots. 200R pots should be sufficient, and only two legs connected this time. Below is a gang of 3 x 500R pots I made for a JAMMA PCB supergun setup + GreenAntz to component-modded TV.
The pots are Bourne cermet multiturn pots - much more precise and durable than the typical cheap carbon film ones. Not that much more expensive, and I can re-use the RGB gang with other projects.
For more on that project:
http://forum.arcadecontrols.com/index.php/topic,165142.msg1741501.html#msg1741501
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