Simple RGB to YPbPr Module

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elvis
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Re: Simple RGB to YPbPr Module

Post by elvis »

nmalinoski wrote:I'd like to see a version of this with a DE-15 input, or maybe even BNC, for taking RGBS from an Extron CrossPoint, VGA switch, or RGB interface without needing a $45-$50 SCART adapter.
If I can extend the feature creep - throw a sync combiner in for folks generating 15/31KHz RGB from a PC, and I'd buy three of these suckers in a heartbeat.
nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

elvis wrote:
nmalinoski wrote:I'd like to see a version of this with a DE-15 input, or maybe even BNC, for taking RGBS from an Extron CrossPoint, VGA switch, or RGB interface without needing a $45-$50 SCART adapter.
If I can extend the feature creep - throw a sync combiner in for folks generating 15/31KHz RGB from a PC, and I'd buy three of these suckers in a heartbeat.
If we're going all-in-one, let's combine the RGB interface features you're asking for with the YPbPr transcoding. For input, DE-15, accepts RGsB, RGBS, RGBHV; automatic detection of sync type.

For output, we want RGBS, RGBHV, and/or YPbPr, so some combination of 6x BNC for RGB, composite sync, and horizontal and vertical syncs (just connect to whichever you want) or DE-15 for selectable RGBS, RGBHV, RGsB[?], RGBSV (composite as horizontal) and/or YPbPr; perhaps plus 3x RCA for YPbPr, if it's desirable to have simultaneous RGB and YPbPr output.

If we want audio, add either 3.5mm TRS or 2x RCA for input and use 2x RCA plus TOSLINK for output.

Then you have an all-in-one device that should satisfy most peoples' RGB conversion needs, regardless of geographic location, and eliminates the need to track down an Extron 201/202/203 rxi and a SCART to component converter.
samson7point1
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Re: Simple RGB to YPbPr Module

Post by samson7point1 »

nmalinoski wrote: The HD Retrovision RGBS->YPbPr cables are built for specific consoles, not to SCART specifications. They pull 5V from a pin on the console's AV port, not from pin 8 on a SCART connector.

This and this suggest that the most we can really expect on pin 8 from a SCART-compliant device is 5mA (probably less); I'm not sure how much current this transcoder requires, but I would expect it exceeds that.

And, even if pin 8 supplied enough current, it's not guaranteed to be 5V; so additional components would be needed to accommodate anywhere between 5V and 12V, and bring that down to 5V. Those components require space, and it doesn't look like there's any room left on that SCART head board.

It would make more sense to do what HDRV does and produce console-specific cables where it's feasible to get regulated 5V with enough amperage from the console, like the SNES or Genesis.
Bummer
mikechi2
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Re: Simple RGB to YPbPr Module

Post by mikechi2 »

samson7point1 wrote:
nmalinoski wrote: The HD Retrovision RGBS->YPbPr cables are built for specific consoles, not to SCART specifications. They pull 5V from a pin on the console's AV port, not from pin 8 on a SCART connector.

This and this suggest that the most we can really expect on pin 8 from a SCART-compliant device is 5mA (probably less); I'm not sure how much current this transcoder requires, but I would expect it exceeds that.

And, even if pin 8 supplied enough current, it's not guaranteed to be 5V; so additional components would be needed to accommodate anywhere between 5V and 12V, and bring that down to 5V. Those components require space, and it doesn't look like there's any room left on that SCART head board.

It would make more sense to do what HDRV does and produce console-specific cables where it's feasible to get regulated 5V with enough amperage from the console, like the SNES or Genesis.
Bummer
I designed it so that it'll automatically switch between SCART power or external USB power. That way if you use cables from say RGC, where the 5V of the SNES is connected to Pin 8 on the SCART, it'll work without external power.
mikechi2
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Re: Simple RGB to YPbPr Module

Post by mikechi2 »

elvis wrote:
nmalinoski wrote:I'd like to see a version of this with a DE-15 input, or maybe even BNC, for taking RGBS from an Extron CrossPoint, VGA switch, or RGB interface without needing a $45-$50 SCART adapter.
If I can extend the feature creep - throw a sync combiner in for folks generating 15/31KHz RGB from a PC, and I'd buy three of these suckers in a heartbeat.
I might design something later on that it'll take VGA, from say a HDMI-VGA dongle and spit out SCART, YPbPr, Y/C and CVBS with the same precision sync combining circuit I used in the old Pi hats.
Classicgamer
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Re: Simple RGB to YPbPr Module

Post by Classicgamer »

nmalinoski wrote:
Classicgamer wrote:Why not just buy a JROK?


http://www.jrok.com/hardware/RGB.html


I have one. It does a decent job. I used to use it to convert rgb from my 240p mame box to component and SVideo for use on a Sony Trinitron tv.

Unless your time is worth nothing, it's probably the more economical solution vs building one from scratch.

At the least, maybe you could just copy their design to save time?
The JROK doesn't satisfy everyone's needs. Just by glancing at it, it looks like it's primarily for arcade use; it lacks anything recognizable as a standard video input or power connector to most people who are looking for something like this for use with a console. If you're buying this, it looks like you'll need to figure out how to adapt your SCART or DE-15 cables, as well as 5V power, mounting, and a case all on your own. On top of that, this thing costs about $82 USD, and only supports 15kHz video.

For similar cost, you can get the ShinyBow SB-2840, which comes in a metal case, supports 15kHz and 31kHz (480p), has a SCART input and RCA outputs for YPbPr component and stereo audio, and comes with a wall wart PSU.

Or, for $50 USD, you can get that transcoder from New Zealand. Although lacks a case, and it's not clear whether it supports greater than 15kHz video, it has the same I/O connectors as the ShinyBow and uses common MicroUSB for power.

What's neat about the proposed module is that it's extremely simple; it doesn't rely on any electrolytic capacitors (which tend to leak after a number of years or when exposed to a lot of heat), it sounds like it could handle everything from 240p to 1080p, and its simplistic design has the potential to fit into a SCART head, which means the potential for premade, inline SCART/DE-15 RGB to YPbPr component converters--no exposed PCBs, no fabrication required by the buyer, recognizable and common USB for power, and it can probably hit a sweet spot between $40 and $60 (depending on things like parts cost, labor, and popularity). (And no, I'm not telling Mike Chi how to price his devices. :P)

I think most of us are trying to connect RGB-capable game consoles to YPbPr-capable consumer CRTs, not so much arcade boards; so the JROK simply doesn't make sense when products like the SB-2480 or the NZ transcoder are readily available and Mike Chi's is coming in the relatively near future, all at or around the same price and all simply working out of the box with RGB SCART.


It's just a color space converter. It can be used to convert RGB to component or SVideo for any consoles.

The one I have uses a DB15 input.

Once the color space is converted, the actual connectors can be changed with any of the basic adapters. Or, break-out boards with screw terminals are cheap and easily available for scart, DB15, DB9 etc.

If you specifically and only want to go from RGB scart to component video, adapters like this are also cheap and plentiful:

https://www.ebay.com/itm/SCART-RGB-to-Y ... 3f9ab01a6c
jft
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Re: Simple RGB to YPbPr Module

Post by jft »

I had looked at tinkering with that exact LT app note, but I lack the knowledge to implement a dual +/- 3.3V supply it seemed to require.
How are you achieving that with the single +5V of USB?
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Simon Belmont
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Re: Simple RGB to YPbPr Module

Post by Simon Belmont »

When is this going to release?
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evilsim
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Re: Simple RGB to YPbPr Module

Post by evilsim »

very cool mikechi2, I just got my retrotink2k in the mail y/day (in Sydney) and its a lovely thing.
Whilst I prefer to retro play on my JVC or PVM, it's still awesome to have one. This RGBs to YUV project is great, I had hand-made one of these circuits in the past but I have also been able to use Ace's RGB to Component through-hole from oshpark (BA7230..) with the tink2k -- it also works well with my Kramer FC-14 which I bought brand new as I wanted it so much :)

Anyway long story short I am keen to see how this project goes and I will definitely be buying one when you're up to that stage. Your products are great keep up the good work.

I'm happy to do further testing for you on these other RGBs to YUV devices if u are still at the crossroads of which circuit to go forward with.

p.s. amazing how well composite (even stock NES RF->composite) signals come through your retrotink2k!
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NoAffinity
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Re: Simple RGB to YPbPr Module

Post by NoAffinity »

Great to see this is being explored. Speaking of feature creep...or possibly another focused product that people other than just me would be interested - what about rca male rgbs to rca male ypbpr, with the converter board somewhere inline in the cable? I detail my setup here, which could benefit from a single cable/converter: viewtopic.php?p=1342897#p1342897

Possibly my need is a little too niche, but I'm excited to see that what is being talked about here could get me closer to the solution I'm seeking.

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nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

NoAffinity wrote:Great to see this is being explored. Speaking of feature creep...or possibly another focused product that people other than just me would be interested - what about rca male rgbs to rca male ypbpr, with the converter board somewhere inline in the cable? I detail my setup here, which could benefit from a single cable/converter: viewtopic.php?p=1342897#p1342897

Possibly my need is a little too niche, but I'm excited to see that what is being talked about here could get me closer to the solution I'm seeking.
It's designed to fit into a SCART head, so why not? Wire it into a male SCART head and then just attach your five RCA leads.
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James-F
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Re: Simple RGB to YPbPr Module

Post by James-F »

It's a big mistake to power video devices with a MicroUSB since the majority of people will use a phone charger or other switch mode power supply that produced on screen distortion and other noise artifacts if there is no other power regulator down the line like 3.3v or 1.8v powering the video/conversion/amplifier chips,, that I tell you from experience.
The best solution is to use a well filtered LM7805 linear regulator to power the 5v line on the PCB/device itself.

Moreover, in my opinion a box with Scart input and 5 RCA output in a box is the most convenient and mechanically safe solution.
A PCB inside a scart head with cables is a terrible idea that is due to fail from the start.

Also, 60$ will be WAY overpriced for a diy RGB to YPbPr converter, 40$ is the maximum I'm willing to pay for a diy device without a proper enclosure.
The Shinybow SB-2840 is 75$ and it is the best RGB to YPbPr converter you can get, WITH a proper steel enclosure and proper female inputs and outputs.
kassj0peja
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Re: Simple RGB to YPbPr Module

Post by kassj0peja »

What happened to this project, is Mike Chi still working on retro gaming projects?
nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

kassj0peja wrote:What happened to this project, is Mike Chi still working on retro gaming projects?
The RGB to YPbPr transcoder recently went up for preorder on his website: http://www.retrotink.com/
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Re: Simple RGB to YPbPr Module

Post by kassj0peja »

Good to hear. I can not open his website for a few days.

Is he working on other projects too?
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Bahn Yuki
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Re: Simple RGB to YPbPr Module

Post by Bahn Yuki »

He's working on component to Scart also.

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orange808
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Re: Simple RGB to YPbPr Module

Post by orange808 »

I'm really hoping for a compoent to RGBHV option as well. :)

I asked him for it in another thread, but the feature may not be a priority or fit the planned price point.

----------------
Random rambling at nobody in particular:
Of course, wanting that might make me "stupid". Maybe I'm already there. Wat-ever... lmao :D
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Guspaz
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Re: Simple RGB to YPbPr Module

Post by Guspaz »

You could always pair it with a sync processor. Years ago I bought an Extron SC210 sync processor, which accepts any form of sync input (RGsB/RGBS/RGBHV) and outputs all forms of sync (RGsB/RGBS/RGBHV), with some options for sync tweaking (polarity, serrations, some sort of digital processing).
kassj0peja
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Re: Simple RGB to YPbPr Module

Post by kassj0peja »

I would love to see a cheaper Retrotink 2x without component with normal sized HDMI.
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orange808
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Re: Simple RGB to YPbPr Module

Post by orange808 »

Guspaz wrote:You could always pair it with a sync processor. Years ago I bought an Extron SC210 sync processor, which accepts any form of sync input (RGsB/RGBS/RGBHV) and outputs all forms of sync (RGsB/RGBS/RGBHV), with some options for sync tweaking (polarity, serrations, some sort of digital processing).
Yeah. That would work.

Right now, there's an Extron RGB in the chain between the SCART switch and the RGBHV switch, so I guess I'm good either way.

(Although, I would really like to get rid of the SCART switch and every possible SCART cable--at some point--and adding another input to the SCART switch feels counterproductive to me. lol I prefer RGBHV, with HD15 and/or BNC cables for multiple reasons.)
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nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

kassj0peja wrote:I would love to see a cheaper Retrotink 2x without component with normal sized HDMI.
I agree that component on the RT2X is of limited value to those who do not use HD Retrovision's YPbPr cables, or to those who have OSSCs, but it's there fore the people that need it. It's also not terribly difficult to source mini-HDMI-to-HDMI cables.

If you already have an OSSC, you should hold out for VGP's Koryuu product, which is simply composite and S-Video decoder that outputs to YPbPr; it should pair nicely with the OSSC.
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Guspaz
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Re: Simple RGB to YPbPr Module

Post by Guspaz »

The RetroTink's component input is useful for more than just HDRV cables, anybody who has a console that outputs component video but wants to use it on a digital display (or just one that lacks component input) might find it handy.

I doubt it adds much to the cost anyhow, it's the composite and s-video connections that require the NTSC/PAL decoder chip...
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maxtherabbit
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Re: Simple RGB to YPbPr Module

Post by maxtherabbit »

Guspaz wrote:The RetroTink's component input is useful for more than just HDRV cables, anybody who has a console that outputs component video but wants to use it on a digital display (or just one that lacks component input) might find it handy.

I doubt it adds much to the cost anyhow, it's the composite and s-video connections that require the NTSC/PAL decoder chip...
except most (all?) consoles that output component natively support 480p and above, which the RT2x does not
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Guspaz
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Re: Simple RGB to YPbPr Module

Post by Guspaz »

To some extent, maybe. 480p support is not universal on component consoles like the PS2 or GameCube, some games only work in 480i out of the box. So if you've got nothing but an HDMI display and a PS2, a RetroTink taking 480i component input is still going to save you $50-100 over an OSSC setup.

Personally, yeah, I'd just use an OSSC, but I can see the use case for 480i component input.
nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

Guspaz wrote:To some extent, maybe. 480p support is not universal on component consoles like the PS2 or GameCube, some games only work in 480i out of the box. So if you've got nothing but an HDMI display and a PS2, a RetroTink taking 480i component input is still going to save you $50-100 over an OSSC setup.

Personally, yeah, I'd just use an OSSC, but I can see the use case for 480i component input.
It definitely applies to the PS2. There are probably 200 or so games that do support 480p, but the vast majority won't do anything more than 480i or 240p (especially if you're using your PS2 for PS1 games).

Should also work fine for Xbox, Wii, PSP, and GameCube, but almost everything on the Xbox supports 480p at least, and I believe it's the same for the Wii and PSP (PSP outputs in 720p, right?). If you primarily game on these consoles, and have the component cables, I would think an OSSC would be the better, more capable buy.
rama
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Re: Simple RGB to YPbPr Module

Post by rama »

The RetroTink is fine at its price point, but I'd also like to see an entry level Composite / S-Video (only) converter.
It should just do that one job of decoding color as best as possible, and leave everything else alone (if that's even possible these days).
To keep things simple and affordable, such a device should probably output RGBS.

It would be the perfect companion module for upscalers that only work with RGB.
nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

rama wrote:The RetroTink is fine at its price point, but I'd also like to see an entry level Composite / S-Video (only) converter.
It should just do that one job of decoding color as best as possible, and leave everything else alone (if that's even possible these days).
To keep things simple and affordable, such a device should probably output RGBS.

It would be the perfect companion module for upscalers that only work with RGB.
For entry-level, I think any composite/S-Video to HDMI converter off Amazon or AliExpress would be sufficient.

If you have a specific need beyond that, then there's the RT2X, which should perform with less lag than an Amazon/AliExpress unit, and has some options for smoothing.

If you're looking for a companion device for the OSSC, VGP should still be coming out with their Koryuu, which converts composite and S-Video to YPbPr component, so that you can take advantage of the low-pass filters available through AV2 (and AV1). The Koryuu should also be a nice, simple unit for anyone who has a display with YPbPr inputs that will take 240p.
rama
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Re: Simple RGB to YPbPr Module

Post by rama »

nmalinoski:
The problem with the cheapest "AV to HDMI" converters is that their programming is unbelievably bad.
I have 2 different samples of these.
One will not decode color properly if the source is 240p. The other does, but has lots of buffering (lag) and looks bad even then.

You can count on these products to be unusable for gaming.
I've asked one company for a data sheet for one of these chips, but they won't give them out.
For some reason, they prefer to have countless bad products with locked down amateur level firmware instead :/
kassj0peja
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Re: Simple RGB to YPbPr Module

Post by kassj0peja »

If the Retrotink would allow 480p input/passthrough I would have bought it already and the expensive component cables too. But a 480i component signal is not much better than S-Video.

I just need that 480p output to use old consoles with the MClassic on a 1440p monitor. The MClassic is mostly used with my lowend PC and the Xbox One though.

I think there is a much bigger market for a cheaper Retrotink without component input. Or if it gets 480p input it is a serious competitor for the OSSC. Now it is just overpriced in my opinion.
nmalinoski
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Re: Simple RGB to YPbPr Module

Post by nmalinoski »

kassj0peja wrote:I think there is a much bigger market for a cheaper Retrotink without component input. Or if it gets 480p input it is a serious competitor for the OSSC. Now it is just overpriced in my opinion.
I'm not sure how much money would be saved by dropping component support. Mike Chi might save only $3 or $4 per unit dropping the RCA jacks from the design, and redesigning and producing a different PCB layout for an essentially identical product would probably cost more time and money than it's worth.
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