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HDMI to Old CRT

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Zebidee:
OK, looks like you've got it working anyway. It's hard to take good screenshots, but your picture looks pretty clear and you seem to have all the colours.



--- Quote ---I have gotten into the Arcade_OSD Swapped the Resolutions then put into the Emulation mode with multiple resolutions to no avail, I even tried changing the resolutions from the desktop while it was being emulated to the CRT with no Change.
--- End quote ---


I don't understand what "emulation mode" is? You mean EDID emulation? I usually just leave that alone. Despite the name. it has nothing to do with actually using game emulators. It concerns fooling the computer into regarding your TV as a proper monitor. I'm not really an expert with CRT_emulator, but think I recall someone saying that whenever you click that, you should re-generate and re-install the video modes.



--- Quote ---See the Pic below, it's almost as if the Screen Area it's filling is larger than the actual "Viewing" area
--- End quote ---


The pics you show actually look fairly normal. Overscan (the desktop hidden behind screen edges), especially in 640x480i, is typical with TVs.

Later, you can trim the frontporch/backporch of the CRT_emulator modes to minimise overscan, but it will probably never be entirely gone. I get less overscan with desktop set to 720x480i. You can also have a look around in the TV service mode geometry adjustments, but be careful as sometimes it is possible to set values for which TV cannot display an image! Then you'd be stuck.



--- Quote ---So the other issue I can't capture in a video or a picture is the "Flashing" maybe what I'm seeing is a Refresh issue? It occurs around Windows Boxes, menus etc, and the text in the Windows Explorer is pretty garbled, but when you put a Picture or a Video up, you don't get this quick "flashing" (excuse me I'm sure this has a proper term, but i don't know a better way to describe it)
--- End quote ---


Do you mean that the picture does not stay on screen, comes and goes ("flashes") fairly quickly? Maybe rolling picture? But stabilises once you have a window open? This is a strong indication that there is no vertical sync coming through. Possibly no sync at all. This is because the TV, in a desperate move, attempts to guess where the sync is by identifying gaps in TV video signal input. The video signal is more distinct when you have windows on the desktop, making it easier for the TV to guess at beginning and end. You might lose sync for a moment if you try moving windows around on the desktop.

How did you end up doing the sync? You still using the Ultimarc video amp? That outputs composite sync already. Take that, run it through a resistor (depends on sync voltage, but try from 470R up to 1K) into the TV's composite/AV input.

Alternatively, your "flashing" around window edges might simply be that you are noticing interlacing in modes like 640x480i. Interlaced modes refresh lines at half frequency, so there is enough time to draw two lines "interlaced" with each other, in the same time it takes to draw one line in progressive modes like 320x240p. Total screen refresh rate remains the same, twice the lines but each is drawn half as often. The slower line refresh rate is much more obvious around straight lines.  Hard to notice with non-linear images, and you probably won't be able to notice it at all with video, which is why it works for normal TV.

abstract3000:

--- Quote ---but your picture looks pretty clear and you seem to have all the colours.
--- End quote ---
Yeah the picture is clear, yet not so sure about all the colors the Whites are "Really Really Bright" I also opened this Jpeg on the Monitor


And this is What I got




--- Quote ---Do you mean that the picture does not stay on screen, comes and goes ("flashes") fairly quickly? Maybe rolling picture? But stabilises once you have a window open? This is a strong indication that there is no vertical sync coming through. Possibly no sync at all. This is because the TV, in a desperate move, attempts to guess where the sync is by identifying gaps in TV video signal input. The video signal is more distinct when you have windows on the desktop, making it easier for the TV to guess at beginning and end. You might lose sync for a moment if you try moving windows around on the desktop.
--- End quote ---

Ok so think of the Windows in the Explorer, and the black lines that make up the border or the windows or the Menus that pop up, now think of a fluorescent light bulb on its way out, how it starts doing that rapid flashing of light (dark bright, dark bright, in rapid recession) and around the desktop Icons themselves the screen is jittery/wavy so your stating refreshing is redrawing itself rapidly but not fast enough for my eyes not to see it I assume that's probably what I'm seeing? Though open a Normal Picture or play a video you don't see any of that (just the Windows components of the operating System)


--- Quote ---How did you end up doing the sync? You still using the Ultimarc video amp? That outputs composite sync already. Take that, run it through a resistor (depends on sync voltage, but try from 470R up to 1K) into the TV's composite/AV input.
--- End quote ---

The synch was just piped on pin 13 through the DB15 last I knew to composite, yes the Ultimarc Video Amp is still in use but not enough power by itself so it is also connected to the PC for power as well.  :banghead: If I unplug that from the PC power supply I get No screen, the instant i plug it In I have screen.

I tried the 720x480 I had available to me in the Arcade_OSD and the Icons dropped even further down in the overscan. The last strange issue I took a video of is when i grab a window and drag it around, when it gets like to the sides or most noticeably the bottom corner is bends the picture as if it's pushing what's there out of the way to make room (Like the clock in the bottom right corner) The clock doesn't disappear but rather bends/distorts slightly like it's making room for the incoming window and when you move it away it bounces right back to normal.

Zebidee:
One last time: put the sync through a resistor 

Without a video, what you describe sounds like you are just noticing interlacing.



--- Quote ---The last strange issue I took a video of is when i grab a window and drag it around, when it gets like to the sides or most noticeably the bottom corner is bends the picture as if it's pushing what's there out of the way to make room (Like the clock in the bottom right corner) The clock doesn't disappear but rather bends/distorts slightly like it's making room for the incoming window and when you move it away it bounces right back to normal.
--- End quote ---


This is "blooming", a very common thing with CRTs. As the image gets brighter, more voltage is being pumped at the CRT phosphors and the picture gets a bit bigger. Better CRTs do it less, but they all do it. Many games actually take advantage of it. For example, try loading up Golden Axe and let it run in demo mode - it takes advantage of blooming when the title comes up on screen.

From that first pic of the test colour field, looks like you may need to adjust the flyback, brightness and RGB cutoffs in the service menu. While you are there, you might find some geometry controls for V and H-size or similar.

You probably also want to play with the CRT_emulator monitor presets, and/or adjust modelines via arcadeOSD, to minimise overscan.

In general though, well done.

abstract3000:

--- Quote ---One last time: put the sync through a resistor
--- End quote ---

I sincerely apologize, I meant to comment on this with my last post but dropped the ball. As mentioned I am alone on this project at this point forward so I will need to source those resistors (470R up to 1K) and most likely a small breadboard, there's no Radio Shacks around so It will be a bit of a drive for me to get those. So that might be a bit before I can give that a shot.

In the meantime I am setting up MAME, the last set I had procured and finely tuned was .206 and I cannot find a version of GroovyMame that far back even through the archives, So transferring the base set now of .260 and when I get that all set up with CRT_Emudriver I want to give it a shot and see what I get on the Screen to give me an Idea of how much time and effort to keep dispensing on this, and fine tuning it out so I have some decisions to make I suppose.

I assume the MAME setup I should have done by tomorrow night, and will probably drag everything to the monitor out in the garage to screw around with it on Thursday some more and have a better Idea of where I really stand with the picture and the purpose.

There are 2 knobs on the back of the Flyback, I have considered looking into giving those some fine adjustments, and as in the Service menu you mean the typical menu you change brightness and Contrast levels? I was going to give that a Shot as well.

I will update you a bit more in a couple days where I'm at and will start looking for the Resistors, will just trace out pin 13, cut it between the small board and the TV Motherboard, plug both ends into a bread board and take turns swapping out the resistors to see if there is any change :)

Zebidee:

--- Quote from: abstract3000 on November 14, 2023, 08:14:57 pm ---
--- Quote ---One last time: put the sync through a resistor
--- End quote ---

I sincerely apologize, I meant to comment on this with my last post but dropped the ball. As mentioned I am alone on this project at this point forward so I will need to source those resistors (470R up to 1K) and most likely a small breadboard, there's no Radio Shacks around so It will be a bit of a drive for me to get those. So that might be a bit before I can give that a shot.
...
I will update you a bit more in a couple days where I'm at and will start looking for the Resistors, will just trace out pin 13, cut it between the small board and the TV Motherboard, plug both ends into a bread board and take turns swapping out the resistors to see if there is any change :)

--- End quote ---


You can buy resistor "kits" online, which have a bunch of different values, for a few dollars. 1/4W rating is plenty for most DIY low-voltage DC stuff that we do. This is really just for your TV's protection from over-voltage and ensuring there are no other issues going on -  but it seems to be working as-is for now.

While you are online, grab some heatshrink tubing. Also, make sure your soldering iron is ready to go :D  You should not need a breadboard for this - just cut the wire, splice the resistor in. When happy, slide some heat-shrink over the join.



--- Quote ---In the meantime I am setting up MAME, the last set I had procured and finely tuned was .206 and I cannot find a version of GroovyMame that far back even through the archives, So transferring the base set now of .260 and when I get that all set up with CRT_Emudriver I want to give it a shot and see what I get on the Screen to give me an Idea of how much time and effort to keep dispensing on this, and fine tuning it out so I have some decisions to make I suppose.

I assume the MAME setup I should have done by tomorrow night, and will probably drag everything to the monitor out in the garage to screw around with it on Thursday some more and have a better Idea of where I really stand with the picture and the purpose.
--- End quote ---


You can download Groovymame 0.206 here




--- Quote ---There are 2 knobs on the back of the Flyback, I have considered looking into giving those some fine adjustments, and as in the Service menu you mean the typical menu you change brightness and Contrast levels? I was going to give that a Shot as well.
--- End quote ---


The bottom knob is the screen voltage. Top knob is focus. Set brightness and contrast in neutral/middle setting, and put a dark screen or game on display (Galaga works OK). Now adjust screen voltage up a little bit, then down until the flyback retrace lines disappear completely. Flyback retrace lines are the faint and slightly diagonal lines you'll see, especially near the top, when screen voltage is high. Once you have the screen voltage right, adjust the focus until everything looks as sharp as possible.

Adjusting flyback is not the same as brightness/contrast, nor is it a substitute. It is more about getting the base level right, and you don't want to be adjusting flyback screen voltage every day. Your brightness/contrast are there for day-to-day fine-tuning.

When I was talking about RGB cutoffs, they are not the same as brightness/contrast either. Cutoffs are the minimum level at which the colours will be displayed. You might see them in the service menu as "RC", "GC" or "BC", or maybe something else. You will not see them in normal TV menu, they are not the same as brightness/contrast. Your display seems to be bright enough, but lacks colours at low brightness levels. That's why I ask about the RGB cutoffs.

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