HDMI to YPbPr converters

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クリスチャン
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HDMI to YPbPr converters

Post by クリスチャン »

Anybody know if these are any good for hooking up say a PC to a 480i CRT? How much latency is involved and is there any scaling when the resolution is 1:1?

https://www.amazon.com/gp/product/B017L ... K2VKV9M9YX

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makar1
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Re: HDMI to YPbPr converters

Post by makar1 »

You could try this converter recommended for connecting the Retrotink 2X to the OSSC:

https://www.retrorgb.com/retrotink-2x-t ... e-chi.html
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Kez
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Re: HDMI to YPbPr converters

Post by Kez »

Hooking up a PC to a 480i CRT is not as simple as getting a converter unfortunately. You need to downconvert the signal, which devices like this won't do.
SavagePencil
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Re: HDMI to YPbPr converters

Post by SavagePencil »

I’d recommend taking a look at Fudoh’s site about downscaling: http://scanlines.hazard-city.de/

I personally use a VSC 900, but there are other alternatives!
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Guspaz
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Re: HDMI to YPbPr converters

Post by Guspaz »

Kez wrote:Hooking up a PC to a 480i CRT is not as simple as getting a converter unfortunately. You need to downconvert the signal, which devices like this won't do.
The device in question has an integrated scaler and claims to support 480i output, though of course this is not ideal for 240p (or upscaled 240p) content.
rama
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Re: HDMI to YPbPr converters

Post by rama »

If you want your PC on a 15kHz TV, why not build a VGA to SCART cable?
There's various tools to get a 240p super resolution going.
nmalinoski
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Re: HDMI to YPbPr converters

Post by nmalinoski »

rama wrote:If you want your PC on a 15kHz TV, why not build a VGA to SCART cable?
There's various tools to get a 240p super resolution going.
If he's in the US, SCART CRTs are unobtanium, and YPbPr is as good as it gets.
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クリスチャン
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Re: HDMI to YPbPr converters

Post by クリスチャン »

It seems despite many saying otherwise, 15KHz on HDMI is possible on nvidia cards (just tested it). I found some info on the actual DAC many of these converters use (the ones without scalers) and it seems to be some type of Lontium chip. These Lontium DACs are apparently able to pass on whatever they receive, including 15KHz, untouched to the analog output. I ended up buying one of these: https://www.amazon.com/gp/product/B07V8 ... UTF8&psc=1 I'll report back with how well it works once it arrives.
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maxtherabbit
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Re: HDMI to YPbPr converters

Post by maxtherabbit »

クリスチャン wrote:It seems despite many saying otherwise, 15KHz on HDMI is possible on nvidia cards (just tested it). I found some info on the actual DAC many of these converters use (the ones without scalers) and it seems to be some type of Lontium chip. These Lontium DACs are apparently able to pass on whatever they receive, including 15KHz, untouched to the analog output. I ended up buying one of these: https://www.amazon.com/gp/product/B07V8 ... UTF8&psc=1 I'll report back with how well it works once it arrives.
http://www.lontiumsemi.com/uploadfiles/ ... _Brief.pdf

that's the DAC inside my Portta HDMI->VGA box, and I can confirm it tolerates 15kHz (both 240p/480i) as well as 480p and up just fine

it also has no lag, I tested it - and no black crush

only catch is you must feed it full range RGB over HDMI if you want correct black/white levels on the output
fernan1234
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Re: HDMI to YPbPr converters

Post by fernan1234 »

If the 480i CRT has RGB input I'd also vote for an HDMI-VGA converter. Keep it all RGB. Was never satisfied with colors going to YPbPr. You would most likely need a sync combiner unit though, so it's a bulkier setup.
energizerfellow‌
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Re: HDMI to YPbPr converters

Post by energizerfellow‌ »

Anybody try the latest batch of cheap HDMI to SCART converters? It's so cheap it's likely just a raw DAC w/o a scaler. It's available under a bunch of brands too.

https://www.amazon.com/dp/B06XWSH129
https://www.amazon.com/dp/B0771MMCL6
https://www.aliexpress.com/item/32966545498.html
https://www.aliexpress.com/item/32823445938.html

EDIT: Never mind, looks like it's just CVBS output on those bad boys.
Last edited by energizerfellow‌ on Thu Aug 08, 2019 10:36 pm, edited 1 time in total.
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クリスチャン
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Re: HDMI to YPbPr converters

Post by クリスチャン »

maxtherabbit wrote:
クリスチャン wrote:It seems despite many saying otherwise, 15KHz on HDMI is possible on nvidia cards (just tested it). I found some info on the actual DAC many of these converters use (the ones without scalers) and it seems to be some type of Lontium chip. These Lontium DACs are apparently able to pass on whatever they receive, including 15KHz, untouched to the analog output. I ended up buying one of these: https://www.amazon.com/gp/product/B07V8 ... UTF8&psc=1 I'll report back with how well it works once it arrives.
http://www.lontiumsemi.com/uploadfiles/ ... _Brief.pdf

that's the DAC inside my Portta HDMI->VGA box, and I can confirm it tolerates 15kHz (both 240p/480i) as well as 480p and up just fine

it also has no lag, I tested it - and no black crush

only catch is you must feed it full range RGB over HDMI if you want correct black/white levels on the output
Now that's interesting. I was going to feed it YCbCr 4:4:4 to avoid any color space conversion; can you confirm if it crushes that sort of signal?
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Fudoh
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Re: HDMI to YPbPr converters

Post by Fudoh »

Anybody try the latest batch of cheap HDMI to SCART converters? It's so cheap it's likely just a raw DAC w/o a scaler. It's available under a bunch of brands too.
HDMI to Scart always uses scaling. These are certainly the least usable converters out there. Why would you want a 480i signal from a HD HDMI source ?
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maxtherabbit
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Re: HDMI to YPbPr converters

Post by maxtherabbit »

クリスチャン wrote:
maxtherabbit wrote:
クリスチャン wrote:It seems despite many saying otherwise, 15KHz on HDMI is possible on nvidia cards (just tested it). I found some info on the actual DAC many of these converters use (the ones without scalers) and it seems to be some type of Lontium chip. These Lontium DACs are apparently able to pass on whatever they receive, including 15KHz, untouched to the analog output. I ended up buying one of these: https://www.amazon.com/gp/product/B07V8 ... UTF8&psc=1 I'll report back with how well it works once it arrives.
http://www.lontiumsemi.com/uploadfiles/ ... _Brief.pdf

that's the DAC inside my Portta HDMI->VGA box, and I can confirm it tolerates 15kHz (both 240p/480i) as well as 480p and up just fine

it also has no lag, I tested it - and no black crush

only catch is you must feed it full range RGB over HDMI if you want correct black/white levels on the output
Now that's interesting. I was going to feed it YCbCr 4:4:4 to avoid any color space conversion; can you confirm if it crushes that sort of signal?
I was unable to get any output from it with YCbCr input. The only device I had available to generate such a signal for testing was an Apple TV, so don't take my results as definitive.
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クリスチャン
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Re: HDMI to YPbPr converters

Post by クリスチャン »

I've heard people having issues with Apple TVs; maybe something to do with HDCP. A lot of these boxes probably omit HDCP keys or something to reduce cost. The Lontium DAC itself supports HDCP after all.
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