Questions that do not deserve a thread

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lechu
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Re: Questions that do not deserve a thread

Post by lechu »

Has anyone here calibrated a TCL TV using HCFR? I've been trying to do so for a couple days, but I'm having a lot of difficulty. I've been using the expert picture settings on the phone app, but I just can't get my delta E values correct with it. I feel like there's something I'm missing. (I did my computer monitor and a VGA CRT with little issues).

I end up using these values in the app after measuring, but they seem really extreme, and the picture just looks terrible: https://imgur.com/kAAvBTB
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

ross wrote:How do HD CRTs convert 480i to 960i? Do they simply double every line (in a way the OSSC can't) or do they deinterlace, upscale to 960p, pad out to 1080p, reinterlace, etc.?
AFAIK the tube and deflection circuitry is incapable of displaying a 960i signal. It can only scan at 33kHz or thereabouts, so it's 1080i.


I'll assume you mean an analog 480i signal via the composite or component inputs; such a signal is first routed to a stand-alone, third-party chip that converts it into a digital signal. From there, it goes to the Sony DRC chip which converts it to 1080i. I'm not 100% sure what the DRC chip does to the signal at that point, and Sony never published what they do, so no one can verify anything, but people have their assumptions based on subjective analysis of the resulting image. FWIW, I think the image gets scaled to fit the center of the buffer in the 1080i raster, and then stretched vertically to make up the difference. In addition to being scaled, the DRC chip also clearly performs some "enhancement" to the image, digitally.
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

ross wrote:Sony technical documents apparently state the DRC circuit converts 480i to 960i, with the MDI circuit responsible for converting 960i to 1080i.
I've seen conflicting accounts of this, also on the AVS forum, also by credible members of the forum. I'm not saying that it's wrong, but I can't remember what it looked like the last time I studied the schematic. (which I have done to some extent) I believe it's most likely possible to sort of figure out the chain in that way, but it's been awhile.

Is this DRC digital enhancement defeatable?
Yes. It involves turning off the DRC and adjusting the automatic vertical compression setting in the service menu. Once you do that, anything you input that is 33kHz is output without any molestation at all. If I remember correctly, you have to use either the digital inputs or the component video inputs for this to work. If you input anything else (like a 480i signal) it immediately overrides the DRC bypass and turns on the chip again. This is done because the CRT deflection circuitry can't scan down below 1080i.

It requires either a computer with the ability to control your output signal with high degree of precision, or a scaling device capable of turning your console into 1080i or 540p (960x540) . Either resolution is fine and they both display perfectly on the tube. If you go with a scaler option, you'll have to adjust the geometry in the service menu.

I use a Raspberry Pi with an HDMI output and RetroArch or Lakka. That allows you to set the video output in the kernel with modelines. You could also use as PC loaded up with CRT emudriver and tweak the hell out things.

I personally love the results of this kind of setup, but it's a bit of a pain in the ass to get going for the first time. It was my hope that the OSSC Pro would have the ability to do this scaling (automatic preset from input signal to 1080i/540p centered timings and padded to fit), or at least the ability to create a custom scaling profile that would achieve the same results. I mentioned it in the thread, but I don't know what the chances of it happening are.
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

ross wrote: 480p from an OSSC padded out to 540p with an Extron DSC 301 HD could achieve that, I think. That's what some have been doing to get 960p from the OSSC displaying as 1080p on their flat panels.

Would add about a frame of lag though.
I'm not really looking for a way to play 480i material in 540p, and even if I was, I don't think the OSSC handles deinterlacing well enough for me to use it that way.

What I'm looking for is the ability to watch 480i DVDs in 1080i and play 5 gen console games in 1080i or 1080i/540p in games that do resolution changes (like Dino Crisis). This is possible with a PC and CRT switchres, for example, thought it's a pain to setup (and hasn't seen a lot of updating for the past year).

The best candidate that I haven't tried yet is GBSControl, but I'm too busy for a new project right now, and my HDCRT is in storage anyway. I'll wait to see what happens with the OSSC PRo, and whether it has the functionality.
Remistewart
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Re: Questions that do not deserve a thread

Post by Remistewart »

BVMD24 owner. Today, when I turned on the monitor, there was a shrill screeching coming from the flyback area. I took the top off and can see an orange LED next to the flyback lighting up. The orange light intensifies when I turn the contrast up, and the screen starts to shimmer violently. The light turns off and the screen stabilises when the contrast is turned down. Is the monitor fried?
SamIAm
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Re: Questions that do not deserve a thread

Post by SamIAm »

Surely the function of that orange LED is explained somewhere in the service manual?

https://www.retrorgb.com/servicemanuals.html
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Einzelherz
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Re: Questions that do not deserve a thread

Post by Einzelherz »

I've got a bit of a programming question.

I have an old Altera USB JTAG programmer from ages ago when I was adding palettes to my NESRGB.

The question I have is can I use this programmer to pull hex off of an 8 pin eeprom and then rewrite to it? I've googled a bit but I'm so rusty with all of this that I feel like I'm not asking the correct question.

Thanks in advance!
7evenforce
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Re: Questions that do not deserve a thread

Post by 7evenforce »

Okay, so I'm at my wits end and I really could use some hardware suggestions.

I have my PS3 hooked up to my sony trinitron CRT with YUV component cables. The trinitron takes a 480i signal from the PS3 (the "standard" setting in the PS3's output options). As you may already know, the PS3 has a huge amount of overscan when doing this. Furthermore, blu ray discs play windowboxed. It's also a huge pain to constantly have to change settings in the TV's super secret service menu.

To solve this issue I bought an Extron VSC 900 for its pan and zoom controls and user profiles. Fuck me, it doesn't accept a 480i input. Setting the PS3 to send 480p at 4:3 worked but I could never solve the constant screen tearing i was getting.

So I bought a DVDO iScan VP30 instead since it takes a 480i input and has overscan and underscan adjustment, and again it has user profiles. Fuck me it outputs 480p minimum. Even following the threads made years ago on this forum, I cannot adjust the user aspect ratio settings to output a 480i or 240p 60Hz signal that my TV will display properly.

So I hooked them both up together. Why not? Well, it kinda works but I get grainy horizontal lines everywhere (like how a bad coax connection looks).

Now what do I buy next as a final solution? I come to this forum asking if there is any kind of converter that will do a 480i YUV component pass-through that lets me zoom in, zoom out, and pan, and save it to a profile. Something like the cinemateq picture optimizer 2 except with underscan as well as overscan. Any suggestions before I ebay the VSC 900 and the VP30?
diamondtron
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Re: Questions that do not deserve a thread

Post by diamondtron »

My Extron CVC 300 shows a very thin white line on the right side of the outputted image when there’s lots of blue being displayed. Has anyone experienced something like this? It happens at multiple different resolutions when doing ypbpr -> RGBS and ypbpr -> RGBHV. Every ypbpr to RGB transcoder I try ends up having small problems.
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NewSchoolBoxer
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Re: Questions that do not deserve a thread

Post by NewSchoolBoxer »

vol.2 wrote: What I'm looking for is the ability to watch 480i DVDs in 1080i and play 5 gen console games in 1080i or 1080i/540p in games that do resolution changes (like Dino Crisis). This is possible with a PC and CRT switchres, for example, thought it's a pain to setup (and hasn't seen a lot of updating for the past year).
I saw a streamer who said she used PS3 with Framemeister because PS3 outputs a constant resolution for PS1 games that do resolution changes. Must be case for PS2 as well. Maybe to watch 480i in 1080i I'd consider looking for 2010 and earlier LCDs and Plasmas that capped at 1080i. Not saying they don't convert to 480p but possible they scale to 1080i instead.

Thanks for the advice jd213! I overlooked your post since I had the tab open and didn't refresh before posting. I like the link to the Nichicon capacitors that I see references to being the best to use. Can buy in US but the major suppliers price shipping high, I assume to encourage bulk purchases. Maybe I can write to My Life in Gaming and ask if they know how to open official SFC JP21 cable.
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

NewSchoolBoxer wrote: I saw a streamer who said she used PS3 with Framemeister because PS3 outputs a constant resolution for PS1 games that do resolution changes.
That's interesting to note. I don't actually need to do that though because I can play PSX stuff in emulation at flat 240p on a 15kHz setup.
Maybe to watch 480i in 1080i I'd consider looking for 2010 and earlier LCDs and Plasmas that capped at 1080i. Not saying they don't convert to 480p but possible they scale to 1080i instead.
This would be specifically for watching material on an HDCRT. Yes, they scale everything to 1080i, but I don't like the scaling they do, and they scale everything, while what I'm looking for is a solution that will seamlessly switch between 1080i/540p, scaled and centered in the frame.
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NewSchoolBoxer
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Re: Questions that do not deserve a thread

Post by NewSchoolBoxer »

vol.2 wrote: This would be specifically for watching material on an HDCRT. Yes, they scale everything to 1080i, but I don't like the scaling they do, and they scale everything, while what I'm looking for is a solution that will seamlessly switch between 1080i/540p, scaled and centered in the frame.
Extron makes scaling presentation switchers that can accept 2 Component inputs and has horizontal and vertical image adjustment: https://media.extron.com/public/downloa ... 0-01_B.pdf
Would be convoluted but you could split the Component source and scale one to 1080i with switcher and keep the other at progressive. Perhaps you can find the scaling circuit in the HDCRT and bypass it.

On another note, I see why people downvote most questions on Reddit about PVMs and give no response. Ask if the PVM can support X video type from Y console versus thinking to see if there would be a user manual like all other televisions. Other side is asking why PVM RGB video is bad with various gaps of game console, cable type, video resolution, sync and RGB/COMP setting on PVM and sometimes there is a switcher or the PVM model number that they leave out. If from Raspberry Pi, no given Lakka configuration or emulator settings or shader used.

I think I need to make a written and video guide to the basics and then I can paste the link in every question for 1 cent ad revenue profit.
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

NewSchoolBoxer wrote: Would be convoluted but you could split the Component source and scale one to 1080i with switcher and keep the other at progressive.
Nah. I already have convoluted solutions to the signal path. I'm looking for set-it-and-forget-it. Hoping that OSSC Pro lets that happen. If It doesn't, I'll eventually move on to GBSControl or the Raspberry Pi based scaling solution (which seems to be capable of a lot).

Perhaps you can find the scaling circuit in the HDCRT and bypass it.
You cannot do it. HDCRTs were designed to be fixed scan rate monitors. They are hard set at 33kHz, so you can only display 1080i or 540p. All resolutions are scaled to that, and you were to try bypassing it, you would damage it or just get nothing. You can bypass the digital processing unit, but it maintains the bypass if you feed it a 1080i/540p signal. It has a self-preservation feature that makes sure everything goes to the screen as 33kHz.

On another note, I see why people downvote most questions on Reddit about PVMs and give no response.
I think this happens for a variety of reasons. First of all, they are $$$, and not everyone has money, so it may seem like bragging in some cases to some people. To people who have them, there is a leet syndrome where they think you aught to know that shit already or you should figure it out yourself. And then there is just the dumb questions that don't make any sense because no one knows if there is something wrong with your particular monitor or your particular setup and trying to troubleshoot someone else's mistake remotely is an exercise in futility.
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

NewSchoolBoxer wrote: Would be convoluted but you could split the Component source and scale one to 1080i with switcher and keep the other at progressive.
Nah. I already have convoluted solutions to the signal path. I'm looking for set-it-and-forget-it. Hoping that OSSC Pro lets that happen. If It doesn't, I'll eventually move on to GBSControl or the Raspberry Pi based scaling solution (which seems to be capable of a lot).

Perhaps you can find the scaling circuit in the HDCRT and bypass it.
You cannot do it. HDCRTs were designed to be fixed scan rate monitors. They are hard set at 33kHz, so you can only display 1080i or 540p. All resolutions are scaled to that, and you were to try bypassing it, you would damage it or just get nothing. You can bypass the digital processing unit, but it maintains the bypass if you feed it a 1080i/540p signal. It has a self-preservation feature that makes sure everything goes to the screen as 33kHz.

EDIT: This only pertains to SONY HDCRTs and some others.
On another note, I see why people downvote most questions on Reddit about PVMs and give no response.
I think this happens for a variety of reasons. First of all, they are $$$, and not everyone has money, so it may seem like bragging in some cases to some people. To people who have them, there is a leet syndrome where they think you aught to know that shit already or you should figure it out yourself. And then there is just the dumb questions that don't make any sense because no one knows if there is something wrong with your particular monitor or your particular setup and trying to troubleshoot someone else's mistake remotely is an exercise in futility.

Anyway, reddit is a fucking cesspool so just ignore all that noise. I use it, but very carefully and I don't get involved in anything controversial (even PVM posts).
Last edited by vol.2 on Fri Jan 22, 2021 5:47 pm, edited 1 time in total.
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maxtherabbit
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Re: Questions that do not deserve a thread

Post by maxtherabbit »

vol.2 wrote: You cannot do it. HDCRTs were designed to be fixed scan rate monitors. They are hard set at 33kHz, so you can only display 1080i or 540p. All resolutions are scaled to that, and you were to try bypassing it, you would damage it or just get nothing. You can bypass the digital processing unit, but it maintains the bypass if you feed it a 1080i/540p signal. It has a self-preservation feature that makes sure everything goes to the screen as 33kHz.
This is misinformation. Please stop making this blanket statement. Yes, SOME of them are made that way but I have a samsung that will NATIVELY scan out both 1080i and 480p
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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

maxtherabbit wrote:
vol.2 wrote: You cannot do it. HDCRTs were designed to be fixed scan rate monitors. They are hard set at 33kHz, so you can only display 1080i or 540p. All resolutions are scaled to that, and you were to try bypassing it, you would damage it or just get nothing. You can bypass the digital processing unit, but it maintains the bypass if you feed it a 1080i/540p signal. It has a self-preservation feature that makes sure everything goes to the screen as 33kHz.
This is misinformation. Please stop making this blanket statement. Yes, SOME of them are made that way but I have a samsung that will NATIVELY scan out both 1080i and 480p
Ah sorry MTR. I forgot about the Samsung guys. I'll edit the original statement.
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BuckoA51
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Re: Questions that do not deserve a thread

Post by BuckoA51 »

We all know Groovymame is king when it comes to CRTs and suchlike, but does it have any advantage in terms of input lag reduction when used with a PC connected to a Gsync/freesync monitor or am I just better off using regular Mame in this instance?
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orange808
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Re: Questions that do not deserve a thread

Post by orange808 »

BuckoA51 wrote:We all know Groovymame is king when it comes to CRTs and suchlike, but does it have any advantage in terms of input lag reduction when used with a PC connected to a Gsync/freesync monitor or am I just better off using regular Mame in this instance?

You're still better off with Groovymame. Frame delay is a killer feature that seperates Groovy from the competition. On a powerful new machine, you'll get very good performance. Beyond that, Groovy still has a few other tweaks that aren't going to get merged into main Mame any time soon. Even without additional tweaks, Groovy will outperform stock Mame.

Mame's low latency mode was a nice improvement, but it doesn't close the gap.

Of course, the best option is to ask Calamity directly for a little clarification.
We apologise for the inconvenience
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BuckoA51
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Re: Questions that do not deserve a thread

Post by BuckoA51 »

Perfect thanks, I'll set up Groovymame on my new rig :)
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friedskater
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Re: Questions that do not deserve a thread

Post by friedskater »

If I was to measure the voltage difference on the CVBS input on the back of my Sony 14L4 PVM should I expect a voltage? My multimeter shows -2V on Line A, while Line B and the component inputs reads 0V. Wondering if this is evidence of a dodgy cap?

I'm been having progressive video degredation on two AV modded Famicoms which I had been testing using Line A and I've ruled out pretty much all the alternatives. The one I'm currently testing required the replacement of the capactior on the video output line after about an hour of use.
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NewSchoolBoxer
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Re: Questions that do not deserve a thread

Post by NewSchoolBoxer »

friedskater wrote:If I was to measure the voltage difference on the CVBS input on the back of my Sony 14L4 PVM should I expect a voltage? My multimeter shows -2V on Line A, while Line B and the component inputs reads 0V. Wondering if this is evidence of a dodgy cap?
No, it doesn't really mean anything. You'd expect Line A and B to read the same but CVBS isn't a pure DC or AC signal so it's hard to draw a conclusion.

Think about DC vs AC. 5V battery is 5V DC. Can measure 5V on multimeter no issues. A 5V sinusoidal AC signal, with no DC offset, will measure 5/sqrt(2) ~3.5V in AC mode because it measures Vrms. Basically is the DC equivalent so if you had a light that glowed based on voltage, 3.5V DC = 5V AC = 10Vp-p = 3.5 Vrms. The p-p means "peak to peak" that you would measure with an oscilloscope from the highest voltage level to the lowest, including negative. So a 5V sinusoidal oscillates between +5V and -5V = 10Vp-p. I have to mention because I see PVM manuals use this figure.

My PVM manual defines Composite video as such that it takes on Line A and B: 1.0 Vp-p +3 dB/-6 dB, sync negative
The +3 dB/-6 dB is the error tolerance so the signal can be 1.4 to 0.5Vp-p and work, assuming no other issues.

Composite is a complicated video signal that carries luma, chroma and sync on one wire. Basically why it's blurry. There's no way you can get meaningful measurements with a multimeter or with Component for that matter. The sync is two square waves, the chroma is contained in a sinusoidal colorburst of its own subcarrier frequency and luma is amplitude modulated. The 1Vp-p comes from the max value of luma being +0.7V and vertical sync of -0.3V. The only meaningful way to look at it is with an oscilloscope.

But sure, -2V is an impossible value from a signal that goes from -0.3V to 0.7V. Probably a bad sign and could still have a capacitor problem but it's not proof.
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NewSchoolBoxer
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Re: Questions that do not deserve a thread

Post by NewSchoolBoxer »

Oh wait, you mean you're measuring Line A and B with the PVM turned off. Still doesn't mean anything but different reasoning. I haven't tried to mod or repair a CRT but every guide I come across warning about shocking yourself from capacitors. Can take days or even a week from power off, from what the guides say, for them to dissipate all their energy.

Skipping over explanation of RC time constants, I think that's your problem. If you played Composite on Line B a few days from now and then measured, I think you'd get -2A from there and 0V on Line A. I guess checking that the voltage is decreasing over time at the same (exponentially decreasing) rate from each Line would actually be a decent test if a capacitor is dodgy because the time constant would be different or non-constant.

As to why it's negative voltage, it's about your frame of reference. Negative voltage means it's flowing the opposite direction from your frame of reference. If you opened the CRT, could find a point to measure +2A instead. I would expect charge to flow away from you when viewing from outside.

If you open the CRT and measure things, which is not a beginner task, you'd probably want to use a special ESR meter to determine if capacitors are near end of life. If they've burst and leaked fluid then, well, no need to measure just replace.
friedskater
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Re: Questions that do not deserve a thread

Post by friedskater »

@NewSchoolBoxer

Thanks. Just to clarify, the PVM was turned on but there was no input connected. I had a BNC -> RCA convertor on the input of the PVM, and an RCA->RCA lead connected. I measured the voltage, with my multimeter ground probe on the outer of the RCA plug, and the positive probe on the center. I thought the negative interesting enough to mention, but that's all.

I didn't expect it to mean anything. I'm pretty much clutching at straws. I had been measuring the voltage at the video output of the Famicom. I am aware that composite video is not DC, but I just was checking it wasn't wildly wrong - like I say I was clutching at straws trying to figure out why my two AV mods both starting failing after a similar amount of time. While checking this I noticed the non-zero voltage reading after I had turned off the Fami and thought it a bit strange.
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NewSchoolBoxer
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Re: Questions that do not deserve a thread

Post by NewSchoolBoxer »

Yeah sure! I like your testing approach without an oscilloscope available.

I assume since every pre-HDMI console outputs Composite that you've tested if other source has video degradation after 1 or 2 hours and on Line A and B. Just that you modded the Famicoms leaves room open to speculate. The transient response of circuits tends to be well under 1 ms so that isn't the problem. Taking an hour means something like the console heating up too much due to faulty voltage regular or heat sink. Or was fine but mod put extra heat out by consuming more power. Or console is fine but audio or video signal is over volted due to amp and on edge of what PVM can handle.

That you replaced one capacitor suggests you know what you're doing. Maybe the service manual exists online and the circuit diagrams can narrow down the capacitors you need to check. I haven't heard of a voltage regulator going bad in a PVM but definitely happens on SNES.

One device I like but lost in my move is Kill-A-Watt that measure the power used of electrical devices, even when they are turned off. More features than that but can compare stock Famicom or NES vs modded if you rule out PVM being the issue, as in, it's only Composite from the Famicoms that degrades.
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Re: Questions that do not deserve a thread

Post by NoAffinity »

If I incorporate a lm1881 based sync stripper into the output of my scart switch, will it pass through csync without affecting it?

I have 4 consoles connected to the switch that are csync and 2 that are sync on luma. Looking to clean up the sync on luma signals without affecting the csync'ers.

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vol.2
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Re: Questions that do not deserve a thread

Post by vol.2 »

NoAffinity wrote:If I incorporate a lm1881 based sync stripper into the output of my scart switch, will it pass through csync without affecting it?

I have 4 consoles connected to the switch that are csync and 2 that are sync on luma. Looking to clean up the sync on luma signals without affecting the csync'ers.

Sent from my SM-G955U using Tapatalk
I would say probably fine. Try it first though. https://www.ti.com/lit/ds/symlink/lm188 ... 1582111958

look on page 3 for the waveforms
setiawan
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Re: Questions that do not deserve a thread

Post by setiawan »

Once all the parts come in, my signal chain will look like the following:

Raspberry Pi HDMI -> Portta HDMI to VGA converter -> JVC TM-H150CG (RGBHV input card)

Now I'm wondering, is there the possibility that I might damage my monitor, by sending it the wrong signal? The JVC has 15kHz horizontal sync, so it will handle 240p/480i just fine. But what happens if I accidentally try to send through a 1080p signal?

Will my monitor recognise that it's out of range, and actively refuse to even try to draw the picture? Or will it try to draw the 1080p picture anyway, and potentially damage something internally due to attempting to perform out of spec?
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Fudoh
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Re: Questions that do not deserve a thread

Post by Fudoh »

Yes, you can damage your monitor.

But switching over the Pi to 15khz is rather easy, since you can leave it on a HDMI display while switching the UI to 480i. Then you can switch all the emulators to 240p and test it on your HD display first (even just to verify that you don't get a picture when launching a game, but get back to the 480i menu when you quit out of it). And once you're done switching everything over to 15khz only then you can connect the Pi to your JVC.
setiawan
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Re: Questions that do not deserve a thread

Post by setiawan »

Hmm that's a little concerning. Do you know how bad it would be? E.g. instantly damage when fed the wrong signal? Or perhaps only if it's high enough (1080p vs 480p say), and attempting to display it for long enough (a couple of seconds, or a few minutes maybe)?

I do intend to ensure that only 480i/240p ever gets sent over. In fact, that's basically how it's set up now. However just yesterday I installed Kodi on my pi, and when I booted it for the first time it unexpectedly opened in 1080p. Thankfully right now I'm using a HDMI to S-Video converter and it scales the signal down to 480i before outputting, so no harm was done. With the Portta HDMI to VGA converter though, no such scaling will take place.

I'm sure that kind of scenario will be rare in the future - especially now that I know it can damage the monitor, and these monitors are getting rarer and more expensive, I'll try to be extra careful. I guess I want to know how careful I have to be. If I accidentally send a 1080p signal through, will I have a few seconds to change the signal (or even quickly switch inputs on the monitor) before irreversible damage is done? Or is it more like, send a 1080p signal through and insta-smoke out of the back?
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Re: Questions that do not deserve a thread

Post by NewSchoolBoxer »

More electrical engineering questions, I'm kind of excited.
setiawan wrote:If I incorporate a lm1881 based sync stripper into the output of my scart switch, will it pass through csync without affecting it?
The second paragraph of the chip's datasheet states that the sync signal gets delayed between 40 ns and 200 ns. "This much delay will not usually be significant" if you don't add in further signal processing and you aren't. Still not ideal not to run csync into it but video quality shouldn't be affected.
setiawan wrote:Hmm that's a little concerning. Do you know how bad it would be? E.g. instantly damage when fed the wrong signal? Or perhaps only if it's high enough (1080p vs 480p say), and attempting to display it for long enough (a couple of seconds, or a few minutes maybe)?
This is like the 3.3V knockoff flash carts and X in 1 games on SNES where the correct voltage is 5. Everyone agrees that it could damage the SNES but no way to say how likely the damage is. 1% chance per hour? 0% chance until X part is near end of life? Is 2chip more resistant than 1chip model that had cost cutting measures? Not going to test and find out.

I can tell you that I tested around with 480i -> 480p with PS2 Rock Band progressive mode. My L2 PVM video split video into 2 parts on the screen at 480p but could run video out to SoG computer monitor that had clear video. 480p on consumer CRT scrambles video as expected. No damage but I only tried for a minute. Yes, more risk the higher the resolution.

As to if the damage would occur, you'd have check the +/- dB voltage range on the sync signal, study the video processing circuit on the specific CRT model, see what transistors and voltage regulators are being used, try to simulate the circuit etc. Square wave sync signal is like DC but the transitions have an AC frequency response. Basically, 480i uses 15 kHz horizontal sync, analog 480p / 1080i doubles that to 31 kHz and 720p / 1080p triple or quadruple. When you increase the frequency, you increase the impedance, in a linear amount in a simple circuit. You therefore *decrease the current by that amount. The voltage drop is higher so you may be under the acceptable range. Transistors may have a certain minimum base current to operate as well. Similar under volting issue to SNES then. Low risk but not 0 risk.
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