RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess”: ?

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kitty666cats
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RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess”: ?

Post by kitty666cats »

I’m sure many of you have seen the elusive ‘RsGsBs’ as an option on your Extron, Kramer, etc gear/devices.

What I would really like is to, once and for all, get the model number of some sorta device that natively outputs said signal / some type of monitor that requires it. I have never come across anything that most definitely needs RsGsBs, I’ve only seen hearsay that some super old CRT projectors implement this type of sync, and also hearsay that some obscure/possibly vintage(?) military equipment/computers/displays use it.

Have any of you fine folks ever stumbled upon a device that you can confirm actually requires this odd, obscure variant of RGB? Would love to hear more, if so!
Ikaruga11
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by Ikaruga11 »

That sounds crazy. Also,

RsGB (Sync on Red)
RGBs (Sync on Blue)

Do these signals even exist? I bet it's possible to make those signals. The problem is displays and devices accepting those signals.
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matt
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by matt »

RGB is basically 3 Luma signals, you could add sync to any (or all) of them and likely still be compatible with RGBs equipment.

RsGsBs would be useful for projectors since they have 3 separate monochrome tubes.
SamIAm
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by SamIAm »

If anyone thinks it's interesting, my test signal generator, a Shibasoku TG19CC, outputs RsGsBs.
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kitty666cats
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by kitty666cats »

SamIAm wrote:If anyone thinks it's interesting, my test signal generator, a Shibasoku TG19CC, outputs RsGsBs.
I do think this is interesting, because it reminded me of this device I have been interested in / am wondering if you know of it or have any firsthand expereience! :)

https://www.ebay.com/itm/ShibaSoku-CD10 ... 2845687842

^ Ever hear anything about this or perhaps muck around with one? I've been eyeing it for ages... maybe next time I have a lot of spare spending $ to splurge with, hah
SamIAm
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by SamIAm »

kitty666cats wrote:I do think this is interesting, because it reminded me of this device I have been interested in / am wondering if you know of it or have any firsthand expereience! :)

https://www.ebay.com/itm/ShibaSoku-CD10 ... 2845687842

^ Ever hear anything about this or perhaps muck around with one? I've been eyeing it for ages... maybe next time I have a lot of spare spending $ to splurge with, hah
As it happens, I actually do have experience with variants of this device: the CD902A and CD902B. I picked them both up for a very reasonable price from Yahoo Auctions.

The "A" and "B" actually indicate the generation, while the numbering indicates the options/outputs. The thing about the A generation is that it goes all the way back to the mid-80s. You can expect that that CD10A1 would need a recap, and you can also expect on the order of 100 caps.

Inside possibly all of these devices is the Hitachi HA11580. This appears to be a fairly ordinary chroma decoder.

https://datasheetspdf.com/pdf-file/7862 ... /HA11580/1

But if you look at what's under the hood, you can see that this clearly isn't using a minimal approach to RGB decoding. This is the CD902B:
Spoiler
Image
Spoiler
Image
Notice the labeling of the boards. These devices probably share a lot of circuitry. It could even be that the "10" line fills in some of the empty pads.

In my case, the CD902A had been stored outside for what I can only assume was years and didn't work. The CD902B turns on and kind of works, but the default picture is dark, and sync is a bit unstable. It doesn't look like any of the caps have ever been replaced. One of these days, I'll give that a shot, but it's likely that the unit would then need a recalibration to be performing at it's best, and Shibasoku keeps a tight lid on their service manuals.

If you're lucky, you'll find one that hasn't seen a lot of use, but age alone will probably have an effect on all of them.

One thing I can say is that Y/C separation was quite good, for a device that predates the fancy digital comb filters of the 90s.

Have a look at this advertisement if you haven't seen it already:

https://worldradiohistory.com/hd2/IDX-S ... e-0146.pdf
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kitty666cats
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by kitty666cats »

SamIAm wrote:Have a look at this advertisement if you haven't seen it already:

https://worldradiohistory.com/hd2/IDX-S ... e-0146.pdf
Hehe, I had that chillin in an open tab already ;)

Much more relevant to my thread on decoders, but I will ask here anyway: did you happen to check if 240p was properly processed?

My current monitor has abysmal comb filtering/decoding, so I’ve personally been rocking composite out of my JVC DVR (with a built in VCR - funky unit, can output VHS or connected sources in both 480i and 480p component), into an Extron YCS 100 (external CV to Y/C comb filter with a TBC as well) into a CYP CMT-7 decoder (15kHz RGBS, RGBHV or YUV out). Makes VHS (or Laserdisc ran through the DVR first) in native res RGBS look very nice for the instances where I don’t feel like upscaling/processing said devices :)
SamIAm
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Re: RsGsBs “sync on all” “sync errywhere” “big ol’ sync mess

Post by SamIAm »

kitty666cats wrote:Much more relevant to my thread on decoders, but I will ask here anyway: did you happen to check if 240p was properly processed?
I didn't test mine very far, but I'm 99% sure that these let 240p through unaltered. They don't seem to have much in the way of a digital nerve-center at all, and there are no controls for changing the vertical and horizontal position of the picture. It's most likely that sync is being passed through as-is, I'd say.
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