SyncStrike... REDUX (Looking for Feedback!)

[Chipnetics]

Guys, as most you know I've made the SyncSlayer and the SyncBaby... just building upon that hard work something I've always wanted to do is roll a scanline generator into a sync stripper. This time I'm looking for some feedback before sending out to production and being overly confident . Like with my other stuff it will come with acrylic, black PCB, red standoffs, and look sexy AF.

One thing I really regret with the SyncSlayer is not having USB power, so that's a must on this guy. I'm not too crazy about is having the USB on the side but was going for symmetry and compactness... so I will include a right angle cable with all orders. The scan-line pin-outs along the left and the power source switch on the right are actually all very nice red slide switches I sourced from the Netherlands... I don't have a picture handy but they are going to make this look great. I've never seen any switches like them, I think you'll all be impressed.

I'm going back to the LM1881 on this board. It's cheaper (like a third of the cost), easier to solder, and really does everything the community needs anyhow. I'm also dropping all the power filtering... the LM1881 is pretty forgiving after all. The breakout header is gone... I doubt anyone ever used it. However the savings is going to be negated by the nice slide switches so ultimately I will still sell this around $60-$70 including a VGA cable, micro USB to Type A cable (no wall wart), and acrylic.

What's everyone's thoughts? Looking for feedback - people had great ideas last couple products. Thank you!

[energizerfellow‌]

I like where this is going, but I'd suggest looking at the ISL59885 instead of the LM1881/EL1883. It's more modern with a cleaner, faster output for not much more and should be a drop-in replacement for a LM1881. Slightly skewed images from the LM1881 are a thing. You can also use the HD detect pin of the ISL59885 to create a high-pass/low-pass safety that shunts the video signal to protect CRTs from out of range signal (three position switch for pass/high/low).

I'd also argue that USB Type-C has now been common enough, long enough that it's time to make the change. It's ubiquitous now on non-Apple phones and every electronics store in the land has Type-C cables and chargers for cheap. The Nintendo Switch and Samsung Galaxy S8 really lit a fire under the ass of the Type-C cable market.

[Syntax]

I like where this is going, but I'd suggest looking at the ISL59885 instead of the LM1881/EL1883. It's more modern with a cleaner, faster output for not much more and should be a drop-in replacement for a LM1881. Slightly skewed images from the LM1881 are a thing. You can also use the HD detect pin of the ISL59885 to create a high-pass/low-pass safety that shunts the video signal to protect CRTs from out of range signal (three position switch for pass/high/low).

I'd also argue that USB Type-C has now been common enough, long enough that it's time to make the change. It's ubiquitous now on non-Apple phones and every electronics store in the land has Type-C cables and chargers for cheap. The Nintendo Switch and Samsung Galaxy S8 really lit a fire under the ass of the Type-C cable market.

My thoughts exactly!
Now if you just added a SOG cleaner...

[Chipnetics]

Thanks I'll check out that chip, if it appears to be a drop in swap I'll give it a go!

If I go with USB C I'll have to do some research on the price of the cables. Or not include one at all. Micro USB can be had for peanuts. All we are looking for it the power from it... None of the USB C protocol fancies, so I thought this is a good way for people to use a rather defunct cable. Plug it in and forget about it...

[energizerfellow‌]

I'd also suggest removing the SCART pin 8 power option entirely as officially per-spec it's only a signal detection pin with no power draw allowance, plus can be anywhere from zero to 12 volts. It's more trouble than it's worth.

The more I think about what kind of use a over/under 25khz feature might be, maybe only enable scanlines for a >25hkz source? High/low shunt seems kind of pointless the more I think about it.

As for mini USB cables, I saved a few as backups, but the rest of them have either been cut up or thrown away over the years and I can't imagine I'm alone.

Calling it "euroscart" is also kind of pointless and redundant. The Japanese variant was never called SCART and was pretty rare in the grand scheme of things, even more so now.

SoG support would also be interesting and all those PS2 people would be happy I think.

Make scanline intensity variable with a pot?

[Fudoh]

I would suggest choosing a different name for the project. After all bencao74 here on the board (Arcadeforge) has been offering the his syncstrike for several years now. Any new product is welcome of course and I'm not saying that either is better than the other, but you're confusing customers, google and it's a little bit disrespectful as well.

[Chipnetics]

I would suggest choosing a different name for the project. After all bencao74 here on the board (Arcadeforge) has been offering the his syncstrike for several years now. Any new product is welcome of course and I'm not saying that either is better than the other, but you're confusing customers, google and it's a little bit disrespectful as well.

That's certainly fair, I'll choose a different name. I tried reaching out to him a couple times with no reply. I also saw he has been inactive on the forum for a couple years (going off memory)... So I wasn't sure if he was still making them. I can definitely agree with the Google confusion as well.

[Chipnetics]

I'd also suggest removing the SCART pin 8 power option entirely as officially per-spec it's only a signal detection pin with no power draw allowance, plus can be anywhere from zero to 12 volts. It's more trouble than it's worth.

Make scanline intensity variable with a pot?

Good point on pin 8. I am going to drop it... Plus saves one more switch!

The Scanline pot is a great idea however I feel the scanlines are not terribly prominent (I've built the implemented design before) and won't really need to be kicked down a notch.

[Syntax]

Powering a lm1881 via scart pin 8 with no power conditioning is the devil. Good call.

[Chipnetics]

Should there be a switch to turn the unit on and off or just have it always powered on? I guess that's one adantage to pin 8 power.

[nmalinoski]

SoG support would also be interesting and all those PS2 people would be happy I think.

Being able to detect and cleanly convert RGsB to RGBS would be a neat feature. I'm sure there are a number of PS2 owners that would appreciate a device they could put between their PS2 and their downstream devices that could do that without being and costing as much as an OSSC or a gscartsw 5.x; might even be able to retrofit something like this into those squarish inline SCART audio breakout things.

Also, something like that sounds pretty close to being a miniature RGB interface. If the SCART input was replaced with a DE-15 port (keep the DE-15 output), and it could automatically detect between RGsB, RGBS, and RGBHV and 75Ohm and TTL sync levels; properly clean sync from G, luma, or composite; and have user-configurable (via jumpers?) sync level (75Ohm/TTL) and output sync type (S/HV); then it could serve as a more-readily-available, smaller, and lower-power alternative to Extron's RGB interfaces for connecting their consoles to pro AV gear, like CrossPoints and PVMs/BVMs, while being able to take advantage of cheaper VGA cables and VGA<->BNC adapters.

[energizerfellow‌]

Should there be a switch to turn the unit on and off or just have it always powered on? I guess that's one adantage to pin 8 power.

I'd leave it on all the time, no power switch required.

If you want to clean up the layout and make the physical layout pass-through like a laptop power brick, remember that the SCART connector itself is right-angle, so you'll want the power and output on opposite sides, but have the SCART socket come in from the top/side.

Also, something like that sounds pretty close to being a miniature RGB interface. If the SCART input was replaced with a DE-15 port (keep the DE-15 output), and it could automatically detect between RGsB, RGBS, and RGBHV and 75Ohm and TTL sync levels; properly clean sync from G, luma, or composite; and have user-configurable (via jumpers?) sync level (75Ohm/TTL) and output sync type (S/HV); then it could serve as a more-readily-available, smaller, and lower-power alternative to Extron's RGB interfaces for connecting their consoles to pro AV gear, like CrossPoints and PVMs/BVMs, while being able to take advantage of cheaper VGA cables and VGA<->BNC adapters.

A universal matching box for 1V/5V and 75/500+ ohm in/out with DE15 on each end would be nice and the holy grail would be any combination of RGBs/RGsB/RGBHV in/out.

[Chipnetics]

SoG support would also be interesting and all those PS2 people would be happy I think.

Looked into the ISL59885, it is SOIC8, otherwise identical so no issues implementing. Plus it's only an extra $1.50. I just didn't want to get into a big spec-studying game
I'll revise and reroute the board to incorporate it.

Regarding SoG, I've never dabbled with it... reading the ISL59885 it doesn't clarify if it can latch onto composite sync off the green line (i.e. if I just had jumpers and branched green off into the ISL59885) for PS2 users. If anyone can sketch a solution or recommend some IC's I'll be happy to incorporate. I can email Renesas and ask as well.

Also regarding DE-15 on both ends... I couldn't agree more - SCART adapters are ridiculously hard to source where I live, however wouldn't that alienate Original playstation, Super Nintendo, Nintendo, (few others) as there are no factory/aftermarket AV port to VGA cables???

Thanks for all the help

[maxtherabbit]

wouldn't that alienate Original playstation, Super Nintendo, Nintendo, (few others) as there are no factory/aftermarket AV port to VGA cables???

Thanks for all the help

thought you were fixing that

[Chipnetics]

wouldn't that alienate Original playstation, Super Nintendo, Nintendo, (few others) as there are no factory/aftermarket AV port to VGA cables???

Thanks for all the help

thought you were fixing that

Haha! Slowly but surely.... well played.

[nmalinoski]

Regarding SoG, I've never dabbled with it... reading the ISL59885 it doesn't clarify if it can latch onto composite sync off the green line (i.e. if I just had jumpers and branched green off into the ISL59885) for PS2 users. If anyone can sketch a solution or recommend some IC's I'll be happy to incorporate. I can email Renesas and ask as well.

Should be pretty easy to test with a prototype; and, if it doesn't do SoG, being able to reconfigure S to HV or HV to S should still be good enough for the majority of users. If it does support stripping from Green, then the trick will be swapping S/H from the input for Green and stripping sync from Green going to the output.

Also regarding DE-15 on both ends... I couldn't agree more - SCART adapters are ridiculously hard to source where I live, however wouldn't that alienate Original playstation, Super Nintendo, Nintendo, (few others) as there are no factory/aftermarket AV port to VGA cables???

With Retro-Access's recent custom cable builder, it's possible to get DE-15 cables for the Genesis/MD 1/2/32X, Neo Geo, Jaguar, NES (those fitted with AV Multi-outs), SNES, N64, GameCube, PS1, PS2, and PS3; and the Dreamcast and Xbox 360 are obviously accounted for using aftermarket devices/cables and a first-party cable respectively.

Unfortunately, these custom cables don't exactly fit my cost argument on the console end; a 6-inch (I'm assuming this is used as a patch cable) DE-15 cable with a PlayStation plug and audio leads costs $34, while an otherwise identical custom SCART cable is $30 (and BNC is $46.50 for a 1.5-foot cable, the shortest it would let me configure); however, you can save greatly on VGA switching equipment and adapters over comparable SCART equipment. VGA switchers can be had for far less than the $220-$240 than a gscartsw; and VGA<->BNC adapters are cheaper and bidirectional, where SCART<->BNC adapters are more expensive and unidirectional (unless you get one of the fancy ones with a direction switch).

[energizerfellow‌]

Does anybody even care about scanline generators in 2018? That's an honest question.

[nmalinoski]

Does anybody even care about scanline generators in 2018? That's an honest question.

I don't care about standalone scanline generators, but that's because I have an OSSC to generate scanlines from every console that I'd want them for (I don't even use the SLG on the Toro I use for my Dreamcast), and the UltraHDMI in my primary N64 does as well, although my living room TV is still a sad, nearly-10-year-old 1366x768 panel that makes scanlines look like garbage (and doesn't support 3x/4x/5x from my OSSC :/).

These days, I'm more interested in being able to economically a) decode NTSC and PAL to RGB, b) convert between YPbPr and RGB, c) convert between sync types (SoG, S, HV), and d) play PAL games on a US-market TV. I also have a little interest in downscaling to 240p/480i for being able to display anything in my console collection simultaneously on my main LCD and my SD-only CRT, but I already picked up a Corio2 for that (and I still need to get my CRT hooked back up again to validate that it works as intended).

Of course, none of that means that there aren't other people who might find use in a standalone SLG.

[Chipnetics]

Does anybody even care about scanline generators in 2018? That's an honest question.

Fair question... I still use scanline generators personally on certain games. I've even used my design on my Windows 98 PC (DE-15 each end) and it can be fun to muck around with. It's about $7.00 in parts (2 IC's, 3 switches) and can be disabled. I think it's a decent cheap feature as an external SG will be $30 I'm guessing.

The chief intent of this little project - which was pretty easy to whip out - was to get rid of one more peripheral on my end (external scanline generator), possibly improve latency, and maybe garner a little interest, but I'm more than happy to try and solve the whole RGsB problems - but it may be on a separate spin off project. I currently don't have a PS2 to test with and have about 6 other projects 85%+ complete that I want to put the nail in... so this is something I'll have to chip away at with time and research.

It looks like separating sync from G on the output is pretty easy with an opamp/comparator, and can be done cheaply. So it may be fairly easy to do something similar on the input to feed the ISL59885 if it doesn't already strip it off from G.

I think some of the autodetect features are doable with a demux but haven't given it much thought yet.

[Chipnetics]

The diagram below from TI datasheets shows how to separate sync from G... unfortunately the OPA698 are like $5.50 each, also would need to get the -0.2v somewhere.



Someone else online claims the LM1881 can strip sync off Green successfully. I imagine the Renesas chip will do so as well. If I can find a cheap PS2 locally I'll give this all a whirl!

[Syntax]

I havent looked into it myself but im pretty sure stripping sync of green is easy.

Its having a clean green and bringing it back down to .7vpp (from 1vpp) that's the hard part.

If you keep any sync signal on green most monitors will show a green hue.

[energizerfellow‌]

With the side question being is there anything you really need SoG for on the PS2 that you can't do with YPbPr? Other than some old UNIX workstations and the odd piece of medical imaging equipment, I can't think of anything else that even uses SoG.

[Syntax]

Sony pretty much used SOG in the PS2 to keep things safe.
That and there is no dedicated pin on the AV header for csync.

If you put 31k sync into 15k equipment you can break things.

I've tapped the H V and Csync lines in my PS2 and disabled SOG. Looks so crisp on an old CRT VGA monitor.
But now I have to be careful not to send that signal to my Tvs when its outputting 31k.

Most of the time it will just show a double image but sometimes you can fry the sync circuit in the Tv.

[Chipnetics]

Are there any retro-gaming systems prior to PS2 that use SoG? My interests pretty much stop at PS2 and newer.

I may just develop the board with the Renesas chip, USB C, and call it a day.... mauling it over.

[nmalinoski]

Are there any retro-gaming systems prior to PS2 that use SoG? My interests pretty much stop at PS2 and newer.

I may just develop the board with the Renesas chip, USB C, and call it a day.... mauling it over.

Pretty much only the PS2 and PS3 use sync on green, and only for 480p and better resolutions over RGB on their AV Multi-out; but effectively only the PS2, because the PS3 can do HDMI natively.

[energizerfellow‌]

Pretty much only the PS2 and PS3 use sync on green, and only for 480p and better resolutions over RGB on their AV Multi-out; but effectively only the PS2, because the PS3 can do HDMI natively.

That and I think most people really only wanted SoG as RGB tended to look better under older unshielded sync-on-composite cables back in the day and a lot of automatic SCART switches had issues with the composite video line vanishing when the PS2 went into high-res YPbPr/SoG mode (that the new gscartsw handles OK). I'm on board with eliminating SoG support.

I may just develop the board with the Renesas chip, USB C, and call it a day.... mauling it over.

Sounds like a plan. Would be very nice to have a C/HV sync switch though.

I noticed the Renesas reference design has a sample low-pass filter design that auto-enables on a sub-25khz input, which would be cool to combine with removing the scanlines when receiving said low-res input.

[Chipnetics]

I noticed the Renesas reference design has a sample low-pass filter design that auto-enables on a sub-25khz input, which would be cool to combine with removing the scanlines when receiving said low-res input.

Yeah SoG is out, it would make the board too much money anyhow for a real narrow market.

This is the design so far with the revisions.... I liked the idea someone pointed out of the SCART already being a right angle cable, but I'd pretty much have to reroute the entire board. I've ordered the USB-C to test fit, it *may* be doable on the underside of the SCART connector, can't know for sure without a physical sample.

I guess I'll call it the SyncReaper keeping up with the whole death and destruction theme

I noticed to my surprise the ISL59885 outputs Hsync... I don't think I'll make use of it though and just put Csync to the Hsync line... I did a jumper for it on my SyncSlayer board but I don't think anyone particularly requires true Hsync.

Regarding the scanlines, I thought most people preferred them on low res input? With the flip flops I can really only see the scanlines on low res; they aren't wide enough on high res to be ascertainable...

[maxtherabbit]

But now I have to be careful not to send that signal to my Tvs when its outputting 31k.

Most of the time it will just show a double image but sometimes you can fry the sync circuit in the Tv.

I've always heard that, but never seen any proof of it breaking the sync circuit from "incidental contact"

[BuckoA51]

This is pretty cool and actually similar to a project we considered a while back. Lack of Sync on Green conversion is a bit disappointing but maybe that could be done in a separate product just for PS2?

Some kind of adapter or cable to go back to SCART would be needed too, for European televisions.

[mikechi2]

This is pretty cool and actually similar to a project we considered a while back. Lack of Sync on Green conversion is a bit disappointing but maybe that could be done in a separate product just for PS2?

Some kind of adapter or cable to go back to SCART would be needed too, for European televisions.

I think I have a circuit worked out in my head to remove the sync pulse from Green... but what would the use case be?