Solution to upscale 15kHz to 31kHz

[xga]

Hi All,

I recently picked up a large Grundig CRT TV which has SCART inputs, but has 100Hz processing which cannot be disabled. It also has a VGA input capable of 31kHz (640 x 480), however the interesting thing is the vertical frequency is 60Hz on the VGA input and the image processing is disabled.

I was wanting to see what people recommend for upscaling 15kHz consoles to 31kHz only displays. My list of requirements would be:

Good image quality
Lag free (or close to it)
Ease of use (kind of automatic and not having to change dip switches every time you wanted to use a different console).

I'd use something like an ArcadeForge SLG3000 to generate scanlines (unless there is a solution that has scanlines builtin).

I do have a OSSC and I know there is a wiki on analogue outputs, but I don't think these are focused on 31kHz displays. I'm also aware of the SLG-in-a-Box, but from what I have read, I think there is a bit of lag and image quality isn't the best. The Wei-Ya ACV-011 seems ok, but seems like compatibility isn't perfect and a lot of time is required playing around with dip switches to get it working.

Anyone have anything else they can recommend or know if the OSSC can output 640 x 480) with a HDMI to VGA adaptor? Extron have anything suitable?

[Kez]

OSSC with a decent HDMI to VGA will do this perfectly in line x2 mode.

[Fudoh]

seriously, 100% what Kez said. There's no use in getting anything else when you have an OSSC. Add a 15 EUR HDMI to VGA dongle and you're good to go.

[xga]

Excellent! That's what I wanted to hear. Thanks Kez and Fudoh.

Unless I'm mistaken, that cheap Tendak female HDMI to male VGA/DSUB seems to be the one to get according to this - http://junkerhq.net/xrgb/index.php?titl ... s_for_OSSC?

[Syntax]

Id rather use a GBS, there's less lag, less in the chain, and its cheap to set up.

[bobrocks95]

Id rather use a GBS, there's less lag, less in the chain, and its cheap to set up.

Thought the GBS had a framebuffer that added at least a full frame of lag?

[Hoagtech]

Id rather use a GBS, there's less lag, less in the chain, and its cheap to set up.

There’s more lag in a GBS and no matter what firware your running, the colors are not right on GBS.

It is cheap to setup but getting SCART into the GBS is not out of the box either.

[Syntax]

Left Screen is an LG flatscreen CRT, middle screen is a Sony Multiscan VGA monitor running off a modded GBS, 3rd screen is a low latency Samsung LCD running off the OSSC.



This is not a comparison between OSSC and GBS lag but rather their real world lag test when used on the fastest screens they are capable of running on.

[Hoagtech]

You can not compare a crt to an LCD in the same lag pattern.

Also what DAC are you using with the OSSC?

[Syntax]

Snes 240p lag test
Crt Tv - RGBS
VGA CRT - GBS
LCD - OSSC via DVI mode


Why can't I compare them this way?

[orange808]

I don't have a GBS, but it would be interesting to see some OSSC lag test results with the OSSC chained through the GBS.

Also, the OSSC has the best scanline features of any device. There's no competition.

[Hoagtech]

Because" low latency" Lcd monitors can have anywhere from 24-150ms of delay inherently. A Leo Bodnar test should give you a better idea on the LCD.

CRT's, especially older ones are considered lag free and take about 4-6 ms to display an image

If you wanted to do a fair comparison. You would have to have a lag free DAC connected to the OSSC and compare the image processors on only CRT.

Also your left tv "RGBS" is most likely getting its signal from OSD and not native scart? I can't say lag has been ruled out of that display method. I don't think it does but I don't know

[Syntax]

The way I see it OSSC can not natively display on any of my CRT monitors so I put it on a PC LCD monitor as I figured that would be the lowest lag possible with an OSSC.
I know its always going to be behind everything else because its on an LCD but do you really think OSSC+DAC is going to beat GBS as far as lag goes? To me that's just adding something else to the chain/lag.


I have a multisync PVM here I can hook up and take another picture, kind of wondering if that TV of mine is behind or not now
The TV is actually native scart, the factory just never installed them for us in Aus, so I did it myself.
OSD has its own inputs im pretty sure, if not internal. Its been awhile.
To be fair ill probably take another shot without the OSSC, just GBS across the VGA monitors to see how it differs from OSSC on LCD, but its pretty clear they will be very close.