RGB/YPbPr Intellivision Thoughts

[leonk]

When do you expect restock on your eBay store of the RGB amp? I'd be interested in trying it out.

[the_crayon_king]

@leonk

I didn't want to list until after testing the alternative board. That way people will be able to choose what is more appropriate for their uses. 

From testing so far "Orange Peel [the alt board] looks pretty similar to the V5 "baked potato".

 

 

This is the composite image on the new kit. It looks (to me) as good as the last kit [with the expansion board]. The real test will be RGB. 

Either way it seems passable so far. I will have more updates soon. 

 

If you are certain you would rather have the current board then I can list some. I have like 4 or 5 on hand; and many more I can make.

[leonk]

Is it fair to say that "Baked potato" and "Orange Peel" will use the same color palettes and the RGB output will be identical?  If so, I'm fine with purchasing "Baked Potato".  I only need the RGB output; I've installed many 2600RGB kits and in most cases people only cared about RGB out and requested that I don't connect the SVideo or composite video output.

 

As for Orange Peel and the bypass resistors, whilst it's a nice gesture for those using Sega Genesis 2 (miniDIN 9-pin SCART cables) I think you can't fix bad cable choice.  The SCART cable also has capacitors in there for DC coupling.  By connecting more capacitance in series a user now in effect has reduced the overall DC coupling, potentially introducing noise (shadows, jail bars) in the video output.

 

In my opinion, when choosing a multiAV port for a console that doesn't have one (2600, ColecoVision, 3DO, Intellivision, Atari 8 bit computer, etc) that requires a straight cable, I advocate for using an existing standard (the 8 pin miniDIN used by the XRGB mini)  This standard has been around for over a decade and what's been shipping with NESRGB and 2600RGB.  SCART cable makers sell SCART RGB cables for it as well (they call it the NESRGB SCART cable)

 

Sega set the standard for how the 9 pin miniDIN electrically should behave. Unless the RGB kit generates the exact same TTL levels with no DC coupling caps, it only confuses people. I find many installers (and some cable makers) get confused by the entire TTL vs 75 ohm termination, csync levels vs vsync, etc. and end up choosing the wrong output port (either out of lack of knowledge or some sort of cost savings that tends to backfire).

[+-^CrossBow^-]

50 minutes ago, leonk said:

As for Orange Peel and the bypass resistors, whilst it's a nice gesture for those using Sega Genesis 2 (miniDIN 9-pin SCART cables) I think you can't fix bad cable choice.  The SCART cable also has capacitors in there for DC coupling.  By connecting more capacitance in series a user now in effect has reduced the overall DC coupling, potentially introducing noise (shadows, jail bars) in the video output.

 

In my opinion, when choosing a multiAV port for a console that doesn't have one (2600, ColecoVision, 3DO, Intellivision, Atari 8 bit computer, etc) that requires a straight cable, I advocate for using an existing standard (the 8 pin miniDIN used by the XRGB mini)  This standard has been around for over a decade and what's been shipping with NESRGB and 2600RGB.  SCART cable makers sell SCART RGB cables for it as well (they call it the NESRGB SCART cable)

 

Sega set the standard for how the 9 pin miniDIN electrically should behave. Unless the RGB kit generates the exact same TTL levels with no DC coupling caps, it only confuses people. I find many installers (and some cable makers) get confused by the entire TTL vs 75 ohm termination, csync levels vs vsync, etc. and end up choosing the wrong output port (either out of lack of knowledge or some sort of cost savings that tends to backfire).

I'm not sure where your located, but at least here in the US, 8-pin SCART cables aren't that easy to be found. I ended up having to order mine from RetroGamingCables out of the UK. Conversely to that, 9-pin Genesis RGB SCART can be found quite easily and is used not just on the Genesis/MD systems, but you will also find it present on many other RGB kits such as those for the PCE as an example. Heck even the DB Grafix booster you can buy for the TG16 and PCE from castlemania games uses the 9-pin mini din setup.

 

As for the TTL stuff, it is true that the Genesis outputs a TTL signal, but the cables are designed to drop all that down and use the Csync instead for consumer level use. Additionally, since YUV is being phased out of Crayon's newest board, the ability for people to use HDRetrovision cables with the board is good because then they can get the RGB transcoded for use with component output.

 

Again, not sure where your located, but in all the various service requests I've done for people over the last 4 years, only 2... just 2 of my clients even own the XRGB FM. I will grant you that I've only started to offer any RGB upgrades since this past summer really with the Intellivision and 2600 RGB. But even before that, and currently, most of my clients actually want all of the available outputs I can provide because it gives them the most flexibility for use with various displays. As a result, most of my clients own the OSSC or a Retrotink device. Therefore, they do end up wanting composite,s-video, and RGB if it is possible. So for me Crayon's newest board is a real win because it doesn't force me to have to make my customers get a different cable they may or may not already have on hand and provides my clients with several output options I can install if they really want or need it. Using a 9pin allows for running the composite output from his new board to the 9pin and again allows more flexibility. It is also required for HDRetrovision cables to work since they actually use the composite signal for sync vs the actual csync itself.

 

BTW... Crayon actually provides an 8-pin mini din port in his kits, but I don't end up using them most of the time. That is why Console 5 doesn't tend to offer output jacks with their AV kits is because they leave that up to the installer to determine what is needed for specific case use. 

[leonk]

I'm located in Canada and have been doing mod work for retro consoles since about 2002.  I've installed practically every known RGB, HDMI, ODE and LCD kit and am listed as the recommended installer for Canada for many of the currently available kits.  So I'm pretty familiar with all these standards and common issues.    In no particular order:

 

• Good SCART cables are hard to find no matter where you are in North America because it was never a standard here. Even Retro-Access (in Florida) initially was based in the UK.  Location has never been a gating factor for me when it comes to purchasing quality retro kits and cables. For example, the best 8 pin miniDIN SCART RGB cable is actually sold by Tim Worthington (maker of NESRGB, 2600RGB, ...) from Australia.
• For PCE what DBElectronics (DB Booster) and Terraonion (SSDS3) have done is make sure their 9 pin miniDIN connector puts out the exact same electrical characteristics as a real Sega Genesis 2.  Terraonion's first SSDS3 did not, requiring original owners to install the FU-RGB kit and Terraonion do a recall and then a revB PCB. So just because you use the same port, doesn't make it right.  You need to take into account the electrical characteristics of the signal. They probably chose this port over 8 pin because they wanted to also give customers the option of composite video output.
• There is nothing wrong with using the Genesis 2 9 pin miniDIN with any kit; as long as the kit puts out the same signal as a real Sega Genesis 2.  The currently sold kit does not.  This explains why so many people complain about dim image and try to fix it by choosing the brighter palette; that's not the correct fix.
• Well, back in 2013 ALL my customers were using XRGB mini, and that device is very finicky when it comes to csync levels.  If you're just a hair off the 0.3Vpp, you loose sync.  So I've learned years ago to make sure everything runs within spec.
• Moving forward with the new kit, the 9 pin mini-DIN might be the best option; allowing customers to have RGB, CVideo and HD Retrovision support. (Sounding like a broken record) What I've been trying to emphasize all along is that if you use an existing standard, you should follow the electrical characteristics of that standard. No resistors, no capacitors on the RGBS lines.  A 75 ohm resistor and 220uF tantalum or electrolytic cap should exist on the CVideo output pin on the kit. 

[+-^CrossBow^-]

13 minutes ago, leonk said:

• Good SCART cables are hard to find no matter where you are in North America because it was never a standard here. Even Retro-Access (in Florida) initially was based in the UK.  Location has never been a gating factor for me when it comes to purchasing quality retro kits and cables. For example, the best 8 pin miniDIN SCART RGB cable is actually sold by Tim Worthington (maker of NESRGB, 2600RGB, ...) from Australia.

Curious why you feel this is the case? I also still cannot figure out why Tim's cable design breaks out the audio separately the way it does when everything is already there for the audio through the 8-pin cable already? I do like the cable setup that you can purchase with Tim's kits, but most of my clients already have a 9-pin RGB or other cable. On this last 2600 RGB I just finished up, I didn't even bother with the 3.5mm audio out and just ran the audio straight to the 8-pin port. I did solder in the 3.5mm on the SCART board, but that was more to fill in the space than anything since again, he still has the audio lines wired up from the 8-pin as well. Seems very redundant so perhaps you can explain why he does that?

 

Ahh..getting off topic. I see your point as well, but again most of my clients are either new to RGB or have HDRetrovision cables on hand or something else. I have both 8 and 9pin mini din on hand and just designed a new breakout PCB for the 8-pin PCB mount mini din since the ones I found online didn't have the +5 wired up for some reason so designed my own based on the pinouts from the Retrogaming Cables out of the UK, whose 8-pin cable is designed for the 2600 RGB, XRGB FV, and NESRGB kits. But again, if a client wants composite as well as the RGB, I'm more likely to suggest they go with a 9-pin so that the composite can be wired to that along with the RGB and provide them the means to use either Genesis 2 cable set at that point.

 

[leonk]

4 minutes ago, -^CrossBow^- said:

Curious why you feel this is the case? I also still cannot figure out why Tim's cable design breaks out the audio separately the way it does when everything is already there for the audio through the 8-pin cable already?

It's Tim's way of eliminating any noise in the SCART RGB cable.  I have Retro-Access and Retro Gaming Cables UK SCART RGB cables here. I can pause the game on a bright screen and turn up the volume to 60% or more and hear hum in the audio on my PVM. It's the nature of analog signal. You can install something like a TOSLINK port on an SNES (done that a few times) to eliminate the hum, or run independent audio/video cables like Tim does (which is not very practical) That being said, I don't use his cable as intended; little known fact is if you don't plug the audio cable, audio still passes through the video cable as long as you connect R/L signals to the back of the port inside the console.

 

I've installed hundreds of NESRGB kits since they first came out.  For a vast majority of them I used a Nintendo multiAV port I've salvaged from a dead SNES, N64 or GameCube.  This allowed me to enable all pins on the port and support all video formats (composite, svideo, RGB and HD Retrovision) As a result, I have a bag with a few hundred 8 pin miniDIN ports with the breakout PCB which I reused for all the consoles I mentioned above. The only missing pins on the PCB is R/L audio, but that's an easy fix given the pins on the port are right there.  

 

Surprisingly I haven't had as many customers telling me they use HD Retrovision cables.  Maybe because component video has pretty much been phased out of modern displays? Or after cost of shipping and USD conversion rate, with the cost of 2 cables you can buy a proper scalar.  Those that still use a CRT here tend to use a PVM/BVM with RGB and those that use modern LCD now buy a RetroTink product.  For either, composite video isn't as important.  Taking it back to the current kit (which doesn't have composite out) it too doesn't support HD Retrovision as-is.  I haven't tried it, but you should be able to enable HDRV support by adding a 470 ohm resistor between pin 4 and 5 of the 9 pin miniDIN; HDRV uses cvideo for sync because csync has been a hot mess due to so much confusion.

 

[+-^CrossBow^-]

21 minutes ago, leonk said:

little known fact is if you don't plug the audio cable, audio still passes through the video cable as long as you connect R/L signals to the back of the port inside the console.

Precisely what I did on this last install of mine. Didn't both with the 3.5mm at all and just wired up the audio output from the RGB straight to the 2 audio pins on the jack. But again, to fill in the space on the SCART housing PCB, I did go ahead and install the 3.5mm audio jack there. But... as you said, it isn't needed. 

 

And adding in a resistor and cap from the composite input from a Genesis was how I was able to restore composite sync on a 32x that I installed s-video into for a client. But they wanted to be able to still use HDRetrovision cables as well. Since the 32x composite has to be killed to not interfere with the s-video, that was the only way to restore a sync signal the HDR cables could use.

 

So.. @the_crayon_king let me know when you have your new board ready and I'll be sure to grab a few to have on hand to offer my clients. At that point I will have 2 of the v3 boards that I only advise for YUV output (just installed one of those for a client as that was all they wanted is YUV). Several of your current v5 boards for YUV/RGB, and this new one for those that want all the outputs.

 

[leonk]

5 minutes ago, -^CrossBow^- said:

So.. @the_crayon_king let me know when you have your new board ready and I'll be sure to grab a few to have on hand to offer my clients. At that point I will have 2 of the v3 boards that I only advise for YUV output (just installed one of those for a client as that was all they wanted is YUV). Several of your current v5 boards for YUV/RGB, and this new one for those that want all the outputs.

 

 

When you say YUV, do you mean YPbPr? Traditional component in North America is YPbPr with:

• Y is the luminance or "brightness" (greyscale) component (or the picture in black and white)
• Pb is the difference between blue and Y (B - Y)
• Pr is the difference between red and Y (R - Y)

 

YUV is encoded differently:

• Y is the luminance or "brightness" (greyscale) component (or the picture in black and white)
• U is the blue luminance value (how much blue should be in the picture) with a scaling factor applied.
• V is the red luminance value (how much red should be in the picture) with a scaling factor applied.

PVM, HDRV, consumer TVs use YPbPr. 

 

[the_crayon_king]

S-Video. Weird (but not surprising) how the colors are slightly different on each mode of video. 

 

Just rambling but, 

The 9 pin SEGA style shouldn't be applied as the standard setup to anyone's mod kit design unless it's specifically for SEGA. 

When going from 8 pin config and using a 9 pin SEGA cable you get half as much p-p as you should (dim video but harmless).

When going from SEGA config to a 8 pin you will get twice as much video as you should. A device is expecting 0.7V maybe 0.714V doubling that is probably bad.

Also there are no through hole connectors for the 9 pin. Soldering the 9pin shell to the motherboard is probably out of the question for novices; and means you would have to remove RF. 

So TLDR 8 pin mini din should be the standard since it is the easiest to install; I would prefer the multi-av connector but it is not something I would want to produce/supply myself. 

 

 

I noticed on testing the new board that sync when not terminated (as to make TTL C-sync) gives a very crappy signal. 

This signal is fine when terminated; so I wouldn't try to use this in a TTL sync fashion. If you need TTL sync then there is probably a device which would condition sync to TTL levels like the LM1881. 

 

I will be testing RGB soon. 

[leonk]

I really like how SVideo came out!  The colors are not that much off from what composite picture looks like.

 

As for csync, as long as at the end of the SCART cable you're close to 0.3Vpp it should work.  I know that devices like XRGB are very finicky about the sync voltage.  But other devices (like PVM) can sync to a shoe string.  If you look at the Sony spec of a late 90's PVM, you'll see that CSYNC can support pretty much anything!

 

Edited December 10, 2021 by leonk

[+-^CrossBow^-]

1 hour ago, leonk said:

 

When you say YUV, do you mean YPbPr? Traditional component in North America is YPbPr with:

• Y is the luminance or "brightness" (greyscale) component (or the picture in black and white)
• Pb is the difference between blue and Y (B - Y)
• Pr is the difference between red and Y (R - Y)

Yes, but I do tend to use them interchangeably for simplicity with my clients.

 

42 minutes ago, the_crayon_king said:

Also there are no through hole connectors for the 9 pin. Soldering the 9pin shell to the motherboard is probably out of the question for novices; and means you would have to remove RF. 

Do you mean no panel mount 9-pin similar to what you provide on the 8-pin? That is probably true. And the RF doesn't have to be removed to use the 9-pin other than in the case of the Intelly 2 as there just really isn't anywere else along the main board to solder it down too. But on the model 1 I usually solder them off to the side and that is why I designed the PCB board to help with mounting them in that fashion. The main problem with soldering down the 9-pin or the 8-pin ones I also have upside down in this style, is that on the model 1, the port sits too high for a cable to fit easily, and on the model 2 it sits too low causing fitment issues. That is why I designed the PCB with nearly a 2.5mm thickness on it to help compensate for this so that little to no case modification is needed when using it to replace the RF output opening.

 

And whether to consider the 9-pin standard or not... it seems to be the most commonly used one in the RGB installs I've seen being used. Followed closely by using the Nintendo multi-out connectors. I've even wondered if the ones that Laser bear sells can fit in the lower case shell of the Intellivision but I think the shell casing might be a bit too shallow with the curve it has.

 

[leonk]

I always cringe when I see the Nintendo multiAV port installed in a non-Nintendo console.  When I used to install Kono's RGB amp a few years ago, here's how I did the RGB install into the Intellivision 1 and 2 with 8 pin miniDIN.

 

 

[+-^CrossBow^-]

57 minutes ago, leonk said:

I always cringe when I see the Nintendo multiAV port installed in a non-Nintendo console.  When I used to install Kono's RGB amp a few years ago, here's how I did the RGB install into the Intellivision 1 and 2 with 8 pin miniDIN.

 

 

 

How did you create the opening through the vented slats of the plastic without it breaking? What does it look like when looking at it straight on? I would like do this but have installed it in the bottom section where the plastic is more solid for rigidity like I do with RCAs.

 

[the_crayon_king]

This is a direct capture of the RGB through OSSC 4X mode > datapath capture card. 

Looks better when going directly to the TV in 5X mode.

 

I still have more things to test but so far (except for TTL sync) it looks like a decent board. 

[leonk]

@the_crayon_king Is it fair to say that "Baked potato" and "Orange Peel" will use the same color palettes and the RGB output will be identical?  As far as you know, there won't be new firmware updates to Baked potato?

[leonk]

14 minutes ago, -^CrossBow^- said:

How did you create the opening through the vented slats of the plastic without it breaking? What does it look like when looking at it straight on? I would like do this but have installed it in the bottom section where the plastic is more solid for rigidity like I do with RCAs.

 

 

When you look straight at the opening it looks stock.  If you have high quality, professional stepper drill bits, it's no big deal to drill it out without breaking the vents.  The Intellivision 2 plastic can handle it.  I've done it a few times with no problem.

 

 

[leonk]

16 minutes ago, the_crayon_king said:

 

I really like the RGB color palette you're using.  Here's a comparison of the colors for those wondering:

 

TOP: the same screen on my LCD (XRGB mini running Fred Kono's RGB board)

MIDDLE: Fred Kono on a PVM

BOTTOM: RF to my test monitor

 

I think the best way to compare the colors is to look at the colors sample bar at the top of the attract screen.  You got the most accurate "beige" (left of red).

 

 

[the_crayon_king]

5 minutes ago, leonk said:

@the_crayon_king Is it fair to say that "Baked potato" and "Orange Peel" will use the same color palettes and the RGB output will be identical?  As far as you know, there won't be new firmware updates to Baked potato?

The color palettes should be the same for the most part as far as data in/out the R2R DAC (Orange peel) uses 8 bits whereas the Video DAC (baked  potato) uses 7. 

That just means there are less possible colors that can be made on baked potato; but you only need 16 so...TLDR no significant difference in the palette values other than an extra bit. 

None of that matters just FYI; just gee wiz info.

 

The colors can still be different since the methods are so different:

The little box is Orange Peel. The bigger one is baked potato. 

These were captured with different settings but it gives a rough idea of the colors being slightly different. 

 

Later tonight I will do a capture back to back with the same settings and we will have a better comparison.

There is still the possibility I might have to change out those 3 resistors values that I had mentioned previously. 

[the_crayon_king]

This is a size comparison with Yannick's board. Purple is Orange Peel, grey is Yannick's:

 

This is a comparison with Baked Potato; Orange Peel is on the bottom:

 

Color compare of Backed Potato "BP" and Orange Peel "OP". If I hadn't labeled these I would have no idea which is which. 

The only obvious color difference (to me) is the background Green/Brown color. 

 

 

TLDR I will make a batch of the new boards and have them up later tonight or tomorrow.

This great since these are so much easier for me to make; I could make 3 (or more) in the time it takes to make one baked potato board. 

 

Let me know if you have any questions or comments. 

[YannAros]

Nothing important but my latest (V2.0) boards are now smaller :

 

Edited December 13, 2021 by YannAros

[the_crayon_king]

12 hours ago, YannAros said:

Nothing important but my latest (V2.0) boards are now smaller :

 

Interesting I didn't know it had changed that much in size. It appears like it is roughly the same size as the Orange Peel board (with your board being slightly smaller.)

Anyway it looks good. That must be the one for sale over at console5 right?

 

 

 

Anyway, for those wondering I am still in the process of taking pictures and writing a basic tutorial.

Here is the ebay link: https://www.ebay.com/itm/284566484576

 

I did a batch of 10 and confirm they are all working. 

It should be noted these can flashed to work on the other consoles (O2, Aquarius, Arcadia 2001) just like the Baked Potato board. 

 

 

[YannAros]

13 hours ago, the_crayon_king said:

Interesting I didn't know it had changed that much in size. It appears like it is roughly the same size as the Orange Peel board (with your board being slightly smaller.)

Anyway it looks good. That must be the one for sale over at console5 right?

I reduced the size when working with @-^CrossBow^- to adapt the board for the NTSC versions, and this is the one that was available at Console5.

The bigger siez of the Frennch variant was really made to be mounted at the place of the power supply PCB that is not present in this version.

 

It's fun that we have ended up with board of very similar sizes, even if yours has more features.

[+-^CrossBow^-]

1 hour ago, YannAros said:

this is the one that was available at Console5.

Yeap I see that C5 is currently sold out of your boards. Is there a replacement shipment to be provided in the future?

 

@the_crayon_king I did purchase 2 Orange Peel boards last night. Likely swap it out with the one in my Intelly 2 that has a v5 Potato in it or maybe install it into a different Intelly 2 I have that is a spare.

 

[the_crayon_king]

12 hours ago, YannAros said:

It's fun that we have ended up with board of very similar sizes, even if yours has more features.

I think the size is just right; big enough to solder in the parts needed, while being small enough to place about anywhere.

I am sure either one of could make our boards even smaller., but I don't see the point. 

 

10 hours ago, -^CrossBow^- said:

 I did purchase 2 Orange Peel boards last night. Likely swap it out with the one in my Intelly 2 that has a v5 Potato in it or maybe install it into a different Intelly 2 I have that is a spare.

I mean if you swap it out it should look more or less the same via RGB. The benefit of these boards would be the addition of s-video or composite without needing an extra board; that and the SEGA cable thing.

 

For anyone else reading this keep in mind the "RB" "GB" and "BB" are for RGB bypass; as in bypass the 75 ohm resistors so that this may work on the SEGA cables now without dropping the voltage.

 

I am looking forward to insights you might have comparison wise between the new board and others.