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emmanuelf

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About emmanuelf

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  1. 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.
  2. 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 ....
  3. https://spie.org/samples/TT54.pdf
  4. 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.
  5. 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.
  6. 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.
  7. Look like clock line impedance problem. A resistor on the line close to maria chip is worth a try.
  8. Yes, my mistake : not Y/C but YPbPr...
  9. 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.
  10. Mystery solved 🙂 Values are good 👍 Yes that is where most users could experience loss.
  11. 15ma less in the divider is great : less heat, less power loss, less tempco sensibility 👍 130ma is not anecdotal, around 15% of the 900ma 5v power rail. The external regulated power supply must be in good conditions and the case/cables connector too to minimize power loss. The cables and the PCB of the coleco are well done, not too much additional loss to expect here, the TIP41C used in the power supply is able to deliver 6A so no problems here too, the limiting factor being the transformer. As the regulation is done inside the power bloc, loss should be minimized at all connection points, the most problematic one being the case connector. Did you measure the voltage at the pcb input with you bench voltmeter to see if the loss is before or after the pcb input ?
  12. Ok had forgotten the specified the optimal load to not disturb at the TMS output. And a second opamp stage would be overkill. 👍
  13. To be sure, what I've had in mind was to put the dividers before the MAX4395, with same ratio but higher values, not adding a resistor.
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