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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Nov 28, 2020 10:07 pm 


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no, there was no dedicated PS2 version of Sony's JP21 cable. There are two box revisions of the PS1 cable though. One in the brown/black striped classic box and the other one in a newer packaging with a picture of the cable on it.

I think Sony wanted to promote their TVs with the Playstation-style AV input, so cables with that particular connector on both ends became available instead.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Nov 28, 2020 10:28 pm 


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Fudoh wrote:
I think Sony wanted to promote their TVs with the Playstation-style AV input, so cables with that particular connector on both ends became available instead.


Aha. I didn't know that was a thing. I that JP21 was a flop though, so it doesn't surprise me that they stopped using it.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sun Nov 29, 2020 3:33 am 


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Thanks you two! Glad I'm not crazy for thinking there was no PS2/3 JP21. Also glad I don't collect boxes. Cable is too collectible and valuable to me to pry open. My basic multimeter that came with the soldering kit doesn't measure capacitance ugh but I can get 1-10 ohms on R and G to the common Video GND Multiout pin and Sync In to Sync In. Maybe that's the Effective Series Resistance (ESR) of the capacitors. Sync In passes continuity with Composite Video Multiout pin as expected.

Interesting that the cable comes without pins 2, 4, 6, 8, 10, 12 (Audio Left Out, Audio Ground, Audio Right Out, Sync Ground, Sync Out):
https://imgur.com/a/JyIA5c1 (image link didn't work for me)

No audio breakout so the "In" pins are "Out" from my point of view.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sun Nov 29, 2020 1:38 pm 


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NewSchoolBoxer wrote:
I can get 1-10 ohms on R and G to the common Video GND Multiout pin and Sync In to Sync In. Maybe that's the Effective Series Resistance (ESR) of the capacitors.


You can't get ESR with a multimeter (well, you can if you build a circuit to do it, but it's not the same as resistance).

If you read from Red out to Red in, a series capacitor would make it appear open (no connection) to an ohmmeter. If you get some small resistance, that's likely just the resistance of the line and the connector itself.

(meaning that if it doesn't appear open, there are no caps in the cable)

That would be interesting if there's no caps, because from what Fudoh is saying, they only made PS1 JP21 cables.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sun Nov 29, 2020 7:10 pm 


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I looked into measuring ESR. Yeah, there are meters designed specifically to measure it since regular ones cannot. Thanks for pointing that out.

I did measure RGB pins on the JP21 side to their Ins on the Multiout side and got open connection and no continuity. I realize that capacitors make an open circuit with DC. So the multimeter creates a DC voltage to measure resistance. Makes sense.

What I gather then is that the RGB lines have a capacitor in the cable but I can't prove the μF value. No capacitor on the Sync line due to Sync JP21 to Composite Video Multiout pin having a measurable Resistance and passing continuity. If the caps are 220 μF like PS2 and PS3 have then the Feq is 110 μF. My Life in Gaming video says using a 1000 μF capacitor in the cable to drown out the 220 uF inside the consoles. Makes Feq 180 μF.

I don't see anything wrong with my PS2 RGB picture quality with the PS1 cable. Of course, no one has showed the different capacitor values ever making a difference or proving official Sony RGB cables for PS2 or PS3 exist.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Nov 30, 2020 5:02 pm 



Joined: 11 Nov 2013
Posts: 247
Dochartaigh wrote:
FinalBaton wrote:
Hmmm... I haven't figured out how to type the SIS commands to the Extron (software to use etc)
https://www.extron.com/download/software.aspx?material=2&id=M


For SIS commands, I want to say I found some apps for my ancient iPad 2 which would send the commands over my house network to my Extron Crosspoints. Might have been using the Linux based Terminal on my Mac though (it was so long ago I completely forget...). You can actually embed SIS commands within a HTML link as well some guy on Reddit found on some Extron documentation (I might have linked to it on my Extron Crosspoint touchscreen post here).

I'll PM you the software which might be what you're looking for (think I might have bundled it in the link in my aforementioned touchscreen post too). I'm pretty sure the MVX is the same software the Crosspoints use (the other newer version is for SMX era stuff I believe).


Sorry to resurrect, but what do I need to do to telnet into my Extron DXP 84? I'm trying to change the EDID values. They say they have a default IP of 192.168.254.254, but that doesn't seem to work when I attempt to telnet into it plugged into my router OR when plugged directly into my laptop's ethernet port. The IP returned in Windows' IPCONFIG also doesn't work. What am I missing?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Nov 30, 2020 6:25 pm 



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SavagePencil wrote:
Sorry to resurrect, but what do I need to do to telnet into my Extron DXP 84? I'm trying to change the EDID values. They say they have a default IP of 192.168.254.254, but that doesn't seem to work when I attempt to telnet into it plugged into my router OR when plugged directly into my laptop's ethernet port. The IP returned in Windows' IPCONFIG also doesn't work. What am I missing?

I don't think I've ever had one plug into ethernet first and let me do anything with it - I always had to use a USB to Serial cable the first time + their windows software to turn on DCHP as outlined below, then you can use ethernet regularly afterwards:

viewtopic.php?f=6&t=63212


Yours might be different since it's an Extron DXP (assuming HDMI version), but I think those first steps are the same at least. By the way, what are you using this for? I was never able to get similar Extron HDMI switchers to work - they only (for the majority) like standard-type signals and would give me black screen dropouts (if they would display at all) with a ton of the OSSC signals for instance (if my memory serves I was getting some dropouts on original Xbox 480p too when ran with an Extron DSC 301) – no matter what settings like EDID I changed (and I changed literally every single settings for probably 10+ hours to try to get it to work).


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Nov 30, 2020 6:37 pm 



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Dochartaigh wrote:
I don't think I've ever had one plug into ethernet first and let me do anything with it - I always had to use a USB to Serial cable the first time + their windows software to turn on DCHP as outlined below, then you can use ethernet regularly afterwards:

viewtopic.php?f=6&t=63212


Yours might be different since it's an Extron DXP (assuming HDMI version), but I think those first steps are the same at least. By the way, what are you using this for? I was never able to get similar Extron HDMI switchers to work - they only (for the majority) like standard-type signals and would give me black screen dropouts (if they would display at all) with a ton of the OSSC signals for instance (if my memory serves I was getting some dropouts on original Xbox 480p too when ran with an Extron DSC 301) – no matter what settings like EDID I changed (and I changed literally every single settings for probably 10+ hours to try to get it to work).


I had an AV friend get me the Matrix Switcher program, and I was able to get into it via USB -> Serial port (for some reason it liked being COM3, while it's COM1 for my Corio downscaler). The switch was in Executive mode. I probably should have done a factory reset when I received it.

Adjusting all of my EDIDs to 1080p/60hz/stereo has made it much more reliable. I have a 360, a Switch, a MiSTer, a laptop, and an OSSC routed to it. The reason I started doing this in the first place was the fact that my OSSC was not displaying the gray bar, but would work with 720p signals. The device required multiple attempts to get it to switch properly because a lot of hardware wanted to send a 1080p signal, but the default EDIDs were all 720p. I will update if I am getting drops, but so far it's been fine.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Nov 30, 2020 9:03 pm 



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SavagePencil wrote:
I had an AV friend get me the Matrix Switcher program, and I was able to get into it via USB -> Serial port (for some reason it liked being COM3, while it's COM1 for my Corio downscaler). The switch was in Executive mode. I probably should have done a factory reset when I received it.

Adjusting all of my EDIDs to 1080p/60hz/stereo has made it much more reliable. I have a 360, a Switch, a MiSTer, a laptop, and an OSSC routed to it. The reason I started doing this in the first place was the fact that my OSSC was not displaying the gray bar, but would work with 720p signals. The device required multiple attempts to get it to switch properly because a lot of hardware wanted to send a 1080p signal, but the default EDIDs were all 720p. I will update if I am getting drops, but so far it's been fine.


Mine likes COM4 - seems to be random based on the computer but glad you got in!

Would you mind sharing exactly what setting(s) (like on what tab(s) and options to choose) you used to fix your issues? Might help me or others with these Extron HDMI matrix switches.

I don't have the DXP but the multiplane SMX switcher with HDMI cards from the same Extron line-up/era as the DXP. Could very well explain why yours is working and my two don't like the OSSC (I tried like ~14x consoles on the OSSC, with 2x to 5x - I wish my memory was better or that I took notes but just know some worked but many had dropouts so I stopped using the SMX).


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Mon Nov 30, 2020 9:25 pm 



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EDIT: It's really quite simple to update the EDID.

1. From the Matrix Switchers program, go to Tools -> EDID Settings
2. For each input, select the resolution you are anticipating. For mine, I'm setting 1080p @60hz stereo.
3. The "Advanced Info" button on this dialog can also show you which resolutions have passed through it, which can be very useful!


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Tue Dec 01, 2020 9:03 pm 


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I have the Datapath E1S and sound card for pixel-perfect-ish RGB + Component video but I want to go down the fruit loop to S-Video and Composite pixel-perfect-ish recording as well. Set on Nintendo and Sony 240p/480i. No need to stream.

Is there a device under $150 that is accurate, video quality flaws and all?

My current plan is to buy a VHS+DVD recorder that accepts S-Video and Composite (and RF to boot) and burn to DVD but then I don't know how accurate one make/model is to another.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 03, 2020 7:24 pm 



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NewSchoolBoxer wrote:
I have the Datapath E1S and sound card for pixel-perfect-ish RGB + Component video but I want to go down the fruit loop to S-Video and Composite pixel-perfect-ish recording as well. Set on Nintendo and Sony 240p/480i. No need to stream.

Is there a device under $150 that is accurate, video quality flaws and all?

My current plan is to buy a VHS+DVD recorder that accepts S-Video and Composite (and RF to boot) and burn to DVD but then I don't know how accurate one make/model is to another.

Very interesting! May I ask more details? Do you want a digital signal that is exactly the same as the analog signal (i.e. interlaced, etc.)? What are you wanting to do with that? Compare signals digitally?

I think there can be a big difference between devices, though I'm no expert. One thing that pops into mind is the term "comb filtering". Sounds like you're the first person to want to try this. Let us know what you find out!


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 03, 2020 8:21 pm 



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SavagePencil wrote:
EDIT: It's really quite simple to update the EDID.

1. From the Matrix Switchers program, go to Tools -> EDID Settings
2. For each input, select the resolution you are anticipating. For mine, I'm setting 1080p @60hz stereo.
3. The "Advanced Info" button on this dialog can also show you which resolutions have passed through it, which can be very useful!


Thanks, and same thing I tried on my Extron SMX but unfortunately I still had drop-outs. Oh well, my 2x HDMI splitters and 4x HDMI switcher are working great and have taken the place of my SMX so at least my setup isn't suffering from the incompatability. Glad your DXP is working well!


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 05, 2020 4:43 am 


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@vol.2
I bought a cheap LCR-T4 + 9V battery and co-opted my multimeter's leads to measure JP21 pin 19 (Green) to Multiout pin 12 (Green / Y) and got ~220 μF as expected. No need to open the cable now but cost me $15.
https://imgur.com/dLCPPuA
People say the ESR and Vloss on those kits are inaccurate so I haven't set a baseline to make a better cable.

@Issac Zachary
Thank you! The forum where I learned that only L5 PVMs can display 480p is probably not the best place to ask about recording S-Video. :? Yes, I want exact digital recordings of every cable type. I feel I can trust the ADC on a VHS/DVD Recorder. Not going to treat 240p as 480i. I see recommendations for I-o DATA USB that takes S-Video and Composite. Accepts 240p but I don't know how it's processed. DVD should sample at 44.1 kHz for 29.97 fps recording. I assume it will dodge flickering from 60.0988 fps SNES and 61.1679 Super Game Boy.

If that's Phase 1, Phase 2 is electrically measuring cable quality. We're stuck with "the quality looks better in person" because video is compressed into 4:2:0 on YouTube. I want to prove how good each cable on the market is and promote which are best value for the money. I have a "Proof of Cable Quality" post that elaborates. Phase 3 is profit.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 05, 2020 4:04 pm 



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NewSchoolBoxer wrote:
@vol.2
I bought a cheap LCR-T4 + 9V battery and co-opted my multimeter's leads to measure JP21 pin 19 (Green) to Multiout pin 12 (Green / Y) and got ~220 μF as expected. No need to open the cable now but cost me $15.
https://imgur.com/dLCPPuA
People say the ESR and Vloss on those kits are inaccurate so I haven't set a baseline to make a better cable.

@Issac Zachary
Thank you! The forum where I learned that only L5 PVMs can display 480p is probably not the best place to ask about recording S-Video. :? Yes, I want exact digital recordings of every cable type. I feel I can trust the ADC on a VHS/DVD Recorder. Not going to treat 240p as 480i. I see recommendations for I-o DATA USB that takes S-Video and Composite. Accepts 240p but I don't know how it's processed. DVD should sample at 44.1 kHz for 29.97 fps recording. I assume it will dodge flickering from 60.0988 fps SNES and 61.1679 Super Game Boy.

If that's Phase 1, Phase 2 is electrically measuring cable quality. We're stuck with "the quality looks better in person" because video is compressed into 4:2:0 on YouTube. I want to prove how good each cable on the market is and promote which are best value for the money. I have a "Proof of Cable Quality" post that elaborates. Phase 3 is profit.


Awesome! That would be awesome! Right now I'm using only S-Video on all my consoles (Snes, Wii, PS2). And may stick with S-Video even when I get other consoles I'm interested in just because it looks so good and I haven't had time to attempt to mod my TV to accept RGB nor does it have a component input. By profit do you mean you intend on selling the best cables out there?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Sat Dec 05, 2020 4:30 pm 


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NewSchoolBoxer wrote:
@vol.2
I bought a cheap LCR-T4 + 9V battery and co-opted my multimeter's leads to measure JP21 pin 19 (Green) to Multiout pin 12 (Green / Y) and got ~220 μF as expected. No need to open the cable now but cost me $15.
https://imgur.com/dLCPPuA
People say the ESR and Vloss on those kits are inaccurate so I haven't set a baseline to make a better cable.


Glad you have your answer. I have one of those things, and it's good for quickly checking things. Don't worry about the esr as that is fine for and electrolytic. It's probably small surface mounts inside the cable. Unfortunately, surface mounts from that time period (mid 90's) are notoriously bad and they tend to leak when they see a lot of use. I've found this to be especially true of Sony devices from that time period. (I've recapped many small devices from around then). Then again, it's not a high power spot, so it might be fine. You might want to check it again after 6 mo or a year and see if it changes any.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Wed Dec 09, 2020 8:32 am 


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Anyone own any of those inline TTL -> 75ohm attenuating mini-cables that Retro Access used to make? I was wondering if they are intended to have the male end (1 end is male, 1 is female) connected to the source (like an Extron Crosspoint, etc), or if the male end is intended to be connected to your display...
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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Wed Dec 09, 2020 3:09 pm 



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kitty666cats wrote:
Anyone own any of those inline TTL -> 75ohm attenuating mini-cables that Retro Access used to make? I was wondering if they are intended to have the male end (1 end is male, 1 is female) connected to the source (like an Extron Crosspoint, etc), or if the male end is intended to be connected to your display...

I don't think which end you connect it to makes a difference; it's not directional.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 10, 2020 12:48 am 


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nmalinoski wrote:
kitty666cats wrote:
Anyone own any of those inline TTL -> 75ohm attenuating mini-cables that Retro Access used to make? I was wondering if they are intended to have the male end (1 end is male, 1 is female) connected to the source (like an Extron Crosspoint, etc), or if the male end is intended to be connected to your display...

I don't think which end you connect it to makes a difference; it's not directional.


Cool, thanks for the peace of mind - I definitely didn’t see a discernible difference one way or the other!
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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 10, 2020 8:45 pm 



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Is a Lumagen Radiance any good for deinterlacing with PS2? Are the various radiance models all the same with regards to deinterlacing?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Thu Dec 10, 2020 10:01 pm 


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The deinterlacing is good, but the unfortunately the whole processing chain on the Radiance is 4:2:2 only, so you get chroma upsampling and the Lumagens have always been messy at that. If you don't have the comparison to a pure 4:4:4 processor, it's not that bad, but it can be annoying, since it's otherwise a great machine.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 1:19 am 



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Thanks for the response, I currently have a VP50 for PS2 deinterlacing duties so am already in the 4:2:2 space I beleive. So I don't have a comparison to a 4:4:4 machine. I'm looking at a Radience as a backup device for PS2 deinterlacing in case the VP50 ever fails. Mainly because the prices for some Radience models are less than VP50 prices.
I tried one of the earlier Lumagens with the SIL504 and had no problem with input lag, but it combs a bit too much in comparison with the VP50. Is the Radience deinterlacing more comparable to the VP50 with regards to combing and input lag?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 11:56 am 


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huh, it's been a long time since I compared these two. I think the DVDO is better in terms of video deinterlacing. The Radiance (you're probably looking at something like the XS, XD or XE) is considerably better in scaling though. For deinterlacing the Radiance uses the Gennum VXP (same chip as the Crystalio II), which makes it even weirder, since the Gennum in the CII and in the Optoma retain full 4:4:4 all the time.

If you want a visible upgrade from a VP50 you need a Framemeister. Or you wait how the OSSC Pro's deinterlacing turns out. On the later one chances are that deinterlacing will evolve over time.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 3:59 pm 


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Thanks vol.2! I never thought about surface mounts going bad. I need to test all cables I buy going forward.

To All: Do you see advice floated around that isn't proven? Anything you wanted tested?

[*] I used to be on "keep cables short" train, until I thought about it. Here is a nice Extron chart showing specs of two 75 ohm cables: https://media.extron.com/public/download/files/specs/rg59-spec_062409.pdf
Notice the resistance of the cable is rated by the frequency of the signal and the length in db loss / 100 feet. In analog television non-sync lines you're looking at ~6 MHz so 0.7 db loss at 100 feet. This is linear so 0.07 dB loss at 10 feet of cable. To give meaning, I found a chart using video game cables that gave 25.9 dB for Composite, 27.2 dB for S-Video and 30.4 dB for Component. So you need 185 feet of cable to degrade S-Video into Composite? Like I'm sure there is more noise at longer cable length but how about we actually test what cable limits are? Would be a shame if someone bought a 1 foot cable when they had a 6 foot one.

[*] The loss no one talks about is connecting components together - the interconnections such as SNES to SNES Multiout to Switcher input to output to TV for 4 connections. Not much online about it. One source uses 0.6 * sqrt(frequency in GHz) so 6 MHz is 0.6 * sqrt(0.006 GHz) = 0.05 dB loss per BNC connector: https://www.amphenolrf.com/faq/technical/what-is-insertion-loss-and-how-is-it-specified/

Seems easy enough to chain BNC or RCA connectors together and measure loss at NTSC and PAL frequencies.

[*] I get that "lag free" is a marketing gimmick and in the fine print it states lag is in the nanosecond range. To give, perspective, 1 million nanoseconds is 1 millisecond and one NTSC frame is 16.7 ms. Is okay then. We use CRTs or buy expensive scalers in part to prevent the 1 frame or so of lag from LCD analog to digital conversion. So what about the delay in the cable length, the propagation delay in transistors, rise and fall time in a square wave, capacitance lagging voltage and the 200 MHz clock speed in a typical FPGA? You chain enough ns delays together, when do you mismatch the sync and video signals?

Also, CRTs have lag. Here is a video showing that: https://www.youtube.com/watch?v=tDLQrGKEnVI
Basically, the 60 Hz rate means the top line is colored instantly, middle line at 1/2 frame of lag and bottom at 1 frame.

[*] TTL sync (4-5 Vpp) vs 75 ohm sync (0.3 Vpp) could damage your SCART equipment and television! Could it? Do we actually have capacitors that fry and transistors that get saturated at 5V in television circuits? I'm not saying people should test this on SCART televisions but I did read a thread here stating that, even on the same television, TTL may work or it may mess the colors up. No one mentioned permanent damage but SCART switchers is a different matter and gscartsw isn't covered under warranty when used with superguns. What are our voltage and current limits? https://shmups.system11.org/viewtopic.php?f=6&t=66639


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 4:10 pm 


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NewSchoolBoxer wrote:
[*] TTL sync (4-5 Vpp) vs 75 ohm sync (0.3 Vpp) could damage your SCART equipment and television! Could it?


Impractical to test because it would depend on the individual monitor or TV. You would have to look at the schematic and evaluate the circuit and anything upstream from the input to determine the effect of 5V. That would mean pulling datasheets to look at absolute maximum ratings in addition to a holistic evaluation of the sync input in the system.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 7:39 pm 


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I think you can obsess too much about such things!

1- In terms of cable length, it can become more of an issue if you are not using proper 75 ohm termination, as I believe there is some signal reflection which is magnified over longer cable runs. For example if you take "TTL" csync from a Genesis or SNES, and stick a resistor to bring the voltage down, this is not true 75ohm termination and there is still an impedance mismatch. If you need a long cable, it's probably fine to and the degradation will be negligible.. and I certainly wouldn't worry about a 1 ft vs a 3 ft cable, but why use overly long cables if you don't need to? They are just harder to manage. If your chain ends up with a digital output, you're technically better off making the digital cable longer instead. Personally, I tend to go for the most convenient solution and see how it looks, usually it looks good enough for me and I stop there.

2 - People do talk about this loss. Generally the "optimal" solution is for the cable run to be as short as possible from the console to the display. RetroRGB recently released a SCART coupler partially to address this. [Edit: Sorry I didn't fully parse what you were saying - insertion loss is as you say probably a larger concern than cable length but ultimately it should only be something you investigate if you notice issues in your setup.. not something to fret about beforehand]

3 - Many lag writeups will explain that CRTs are considered the baseline for lag, they are essentially drawing the frame as it arrives and it is not possible to produce a signal any faster. Of course they are not truly 0 lag, and the software they are running has inherent lag also, but for the purposes of measuring lag in your display chain, it is safe to consider a direct CRT connection as 0. In terms of longer cables producing lag, this is so negligible as to not be worth thinking about in any reasonable scenario. Think about how many miles of cable you are passing signal through to talk to someone in another country, and you end up with only a few ms of lag (probably mostly due to other factors as well).

4 - Components have varying tolerance, but these circuits are designed with a particular voltage level in mind. Asking "how off-spec can I get before my stuff breaks?" is not a particularly constructive question. Why do you want to go off-spec? Just use proper video circuits. Plenty of superguns can do this, but the gscartsw has this caveat because people have managed to damage them in the past with dodgy superguns.


Last edited by Kez on Sat Dec 12, 2020 4:15 pm, edited 1 time in total.

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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 9:27 pm 



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Didn't want to make a new thread because everybody and their brother has sync problems at some point, but these are some unique symptoms so hopefully someone can point me in the right direction;

My PVM20M4U has started to lose horizontal sync over RGB upon power up, but I've found if I go into the menu and tweak the video phase value higher, it will restablish sync, even if I return the setting to its initial value afterward, kind of like the amplification of the signal is enough to complete the circuit across some faulty component(s) until the monitor is shut off again.

Additionally, if I'm using something with integrated sync, like a VCR or anything else with composite, I can't seem to establish sync no matter how much I tweak the settings, which would also make sense because that sync signal is much weaker/dirtier.

I know there are schematics, but I suck at reading them. I'm not sure what component of the sync circuit could be responsible for this failure. I had some geometry problems, so I took this as an opportunity to recap the whole deflection board, but the problem still persists. Are there major sync components on the input or neck boards that could be responsible for this? I've come across some info that most or all of the sync is handled by a single IC, but I'll be damned if I can figure out which one.

Any help would be appreciated, thanks dudes.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 9:46 pm 



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Posts: 247
Should I be worried about all my old cartridges with battery backups having the batteries leak?


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 10:01 pm 


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Joined: 05 Mar 2018
Posts: 1383
NewSchoolBoxer wrote:
[*] The loss no one talks about is connecting components together - the interconnections such as SNES to SNES Multiout to Switcher input to output to TV for 4 connections. Not much online about it. One source uses 0.6 * sqrt(frequency in GHz) so 6 MHz is 0.6 * sqrt(0.006 GHz) = 0.05 dB loss per BNC connector: https://www.amphenolrf.com/faq/technical/what-is-insertion-loss-and-how-is-it-specified/

I'm glad you bring up insertion loss. It is a very real issue, and would likely have more effect than cable length in a typical retro setup using coax cables and many various passive adapters. Sticking with one type of connector is best to minimize the quantity of adapters, and impedance controlled connectors are a plus too.


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 Post subject: Re: Questions that do not deserve a thread
PostPosted: Fri Dec 11, 2020 10:33 pm 


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ajdesmarais wrote:
Didn't want to make a new thread because everybody and their brother has sync problems at some point, but these are some unique symptoms so hopefully someone can point me in the right direction;

My PVM20M4U has started to lose horizontal sync over RGB upon power up, but I've found if I go into the menu and tweak the video phase value higher, it will restablish sync, even if I return the setting to its initial value afterward, kind of like the amplification of the signal is enough to complete the circuit across some faulty component(s) until the monitor is shut off again.

Additionally, if I'm using something with integrated sync, like a VCR or anything else with composite, I can't seem to establish sync no matter how much I tweak the settings, which would also make sense because that sync signal is much weaker/dirtier.

I know there are schematics, but I suck at reading them. I'm not sure what component of the sync circuit could be responsible for this failure. I had some geometry problems, so I took this as an opportunity to recap the whole deflection board, but the problem still persists. Are there major sync components on the input or neck boards that could be responsible for this? I've come across some info that most or all of the sync is handled by a single IC, but I'll be damned if I can figure out which one.

Any help would be appreciated, thanks dudes.


Looking at that manual shows the sync goes through components in the Q board. (page 74-75) There are caps, diodes and transistor for each input. However, if you are experiencing sync issues on all inputs, then that probably points to a bigger issue. It's unlikely that a single bad component in the input board is going to ruin the sync for all inputs. (but not impossible if the sync circuit is being shorted out or something.

The sync goes through more than one IC. The main IC in the set, IC101, is the UPD78014FYCW-W23 and that would be part of the sync. I guess if that was bad it would screw things up. It's hard to say. The IC is not made anymore, but you may be able to get it through a sony part place. Probably cost a lot to find out if it's the issue.


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