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emmanuelf

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About emmanuelf

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  1. The current belief is that the problem is the missing hsync pulses. LMH1980/1981 will not solve it. But you are by experiments thinking that it is more a timing problem on the hsync pulses than a problem around the vsync. It should be confirmed by proper measurement on a scope. Perhaps timings IS the problem, perhaps trickling the vsync timing one way or another ( inverted v5 or csync slowing) minimize the missing pulse problem. Investigating all this is on my todo list. My idea is using a little fpga to drive a standard video dac to act as "no longuer available/obsolete" ramdac and to what is need to proper reconstruct a compliant csync. But I have no time now to put all this on the bench ....
  2. Hello, How did you solved the funky non compliant sync signal problem? Most modern tv/panels/converters do not tolerate the absence of hsync during/around vsync. Glad to see that you use a proper output buffering chip. But keep in mind that all signals should be buffered, even csync is subject to 75ohm loading.
  3. I've found 4.433619Mhz smd oscillators. They are on their way. If they work well at 5v as advertised, it should be possible to do a highly integrated thing like a board to put between the maria and his socket.
  4. Equalizing/serration pulse omission don't disturb OSSC sync and most console/electronic devices completely omit them an use plain hsync pulses (XNOR with vsync as needed) A complete hsync pulse omission around vsync is the most coherent explanation of the problem. We will see with the scope capture.
  5. Most color CRT front panel are lead free as you could see in this document and the radiation problem is on the back of the tube which is leaded and coated. But it is nitpick anyway ....
  6. This is inaccurate. Lead glass would glow greenish. Starting at 15kv there is very soft low level radiation produced by the beam, but there are completely unable to pass trough the thickness of the front face (non leaded) glass and are mostly converted to visible light. Very very old not completely coated tube could produce bad radiation, on the back. Like very old high performance scope tube. Even in this case it is irrelevant as they are generally enclosed in a mu-metal cage. Some very specific old vacuum valves produce high level of dangerous radiation, but this is not the topic. Anyway, I'm offtopic too 😋 Nothing will completely replace old CRT like nothing is able to really replace the ungridded vector CRT of the vectrex. But I agree, next gen OLED will help to fade the ugly rendering of old analog systems (and actual one) on modern panel, if properly scaled.
  7. And so you will need to do scaling and be down in the rabbit hole.... a never ending story and definitively not an "ultimate choice". "Good quality HDMI board" with these darn specific old analog sources is a complete subjective concept. The cost will be disruptive too... If you want hdmi, look at the F18A-MK2 and DVI output, but you will not have the right pixel aspect ratio. Or go to the full FPGA emulation route. Good analog->hdmi conversion for these very low resolution sources involve digital conversion and scaling. It is a very complex problem which need it own complete and cost reusable/sharable solution. In my opinion, the only good solution is/will be OSSC Pro. But it is only my opinion.
  8. Giving MARIA is own local color-burst oscillator is perhaps the only way to cure things. With the buffer, what the signal look like on a scope on the maria pin ? Buffer + R on the maria side is perhaps sufficient.
  9. Look like clock line impedance problem. A resistor on the line close to maria chip is worth a try.
  10. Did you ever get this #1 module working some days ? There is at least 3 model : PAL, NTSC and Y/C used for French consoles. The Y/C one is pin incompatible with the standard pal/ntsc consoles.
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