Connecting a PC to a CRT TV via composite

The place for all discussion on gaming hardware
User avatar
NoAffinity
Posts: 1018
Joined: Mon May 07, 2018 5:27 pm
Location: Escondido, CA, USA

Re: Connecting a PC to a CRT TV via composite

Post by NoAffinity »

Well it looked very clean, as good as composite gets. No 480i flicker. The TV out wouldnt work with the stock drivers. I dont remember all the details and test scenarios. Most of the time it wouldn't display. Some times I would get split screen. I got the right combination of gui settings and could then manipulate the res with the pull down res menu.

But I could've just been too excited, thinking I got it working and deliberately overlooked flickering.

I will put the 7000 back in this weekend and see what I can confirm.

:edit: my magewell pro hdmi has composite input and should be able to properly identify the signal.

Sent from my SM-G955U using Tapatalk
User avatar
NoAffinity
Posts: 1018
Joined: Mon May 07, 2018 5:27 pm
Location: Escondido, CA, USA

Re: Connecting a PC to a CRT TV via composite

Post by NoAffinity »

Apologies folks, you're all absolutely right, it is a 480i output. What threw me is that making changes in quickres or the wolfmame pull-down seem to have an effect on how the trinitron handles the signal, but its still a 480i in all cases. :oops: Terribly sorry for the mis-information.
energizerfellow‌
Posts: 208
Joined: Thu Sep 27, 2018 1:04 am

Re: Connecting a PC to a CRT TV via composite

Post by energizerfellow‌ »

Greg2600 wrote:I found an old Monoprice VGA to Component (YPbPr) Converter but after I got it realized the specs only output component over 480p/720p/1080i which is too high for the CRT.
I'll bet money on it working perfectly at 15khz 240p/480i if it doesn't have an internal scaler. It won't "officially" support 15 khz as they probably never bothered to test the VGA input at anything under 31 khz.
nmalinoski
Posts: 1974
Joined: Wed Jul 19, 2017 1:52 pm

Re: Connecting a PC to a CRT TV via composite

Post by nmalinoski »

Greg2600 wrote:What's the best way to convert VGA (say Dreamcast or Laptop) to Component 480i/240p on CRT TV? I found an old Monoprice VGA to Component (YPbPr) Converter but after I got it realized the specs only output component over 480p/720p/1080i which is too high for the CRT.
Some laptops should be able to natively output composite and S-Video. If yours can't, you could use something like a Corio2 to downscale to 480i or 240p.

If you're simply transcoding RGB to YPbPr, like in the case of the Dreamcast (Which is only RGBHV in 480p mode, otherwise RGBS or composite/YC for 480i/576i, all of which determined by the connected cable), then you have your choice between the Retrotek SCBV1P3 (RGBS/SCART->YPbPr/RCA; limited to 480i/576i), the Retrotek VGACTV1 (RGBHV/VGA to YPbPr/RCA, does at least 1080i), linuxbot3000's transcoder (RGBHV/VGA to YPbPr/RCA, unsure of limitations), or the ShinyBow SB-2840 (RGBS/SCART to YPbPr/RCA, limited to 480p).

Personally, I'd handle each device separately. The Corio2 for downscaling output from the laptop; and I'd stick to a transcoder for the Dreamcast, since it does 240p/480i natively, and the transcoder shouldn't add any lag (so light gun games, yay).
User avatar
buttersoft
Posts: 383
Joined: Sun Jul 24, 2016 7:49 am

Re: Connecting a PC to a CRT TV via composite

Post by buttersoft »

NoAffinity wrote:Apologies folks, you're all absolutely right, it is a 480i output. What threw me is that making changes in quickres or the wolfmame pull-down seem to have an effect on how the trinitron handles the signal, but its still a 480i in all cases. :oops: Terribly sorry for the mis-information.
D'oh! Don't sweat the mistake, we've all jumped to conclusions before. It's the heartbreak you've caused us all you should let haunt you :D

That's that then. As i said, i have heard there's a way to get 240p out of some TV-out ports, and if any Spanish speaker wants to jump into the GroovyMAME Chile group and ask politely for some leads, that would be great :) It might be a forced-240p though, but i'm still curious.
User avatar
NoAffinity
Posts: 1018
Joined: Mon May 07, 2018 5:27 pm
Location: Escondido, CA, USA

Re: Connecting a PC to a CRT TV via composite

Post by NoAffinity »

buttersoft wrote:
NoAffinity wrote:Apologies folks, you're all absolutely right, it is a 480i output. What threw me is that making changes in quickres or the wolfmame pull-down seem to have an effect on how the trinitron handles the signal, but its still a 480i in all cases. :oops: Terribly sorry for the mis-information.
D'oh! Don't sweat the mistake, we've all jumped to conclusions before. It's the heartbreak you've caused us all you should let haunt you :D

That's that then. As i said, i have heard there's a way to get 240p out of some TV-out ports, and if any Spanish speaker wants to jump into the GroovyMAME Chile group and ask politely for some leads, that would be great :) It might be a forced-240p though, but i'm still curious.
Thank you sir for letting me off the hook. I'm still embarassed, tho. :oops: :)

But, on to forward thinking. I picked up a HD4350 off of ebay, with s-video output. I'll give that a test too, not that I would expect any difference at this interval, but if some new information comes to light that forces 240p out of the TV out port, I'm ready to test!

One interesting thing, from my limited testing with the composite out port: the TV out doesn't work until Catalyst Control Center is installed. The screen constantly rolls vertically. Once CCC is installed, there's a few apparent re-initilizations of the TV out port after a reboot and once getting to the desktop, and the image is then solid. Wondering if there's some magical setting in CCC that might enable progressive output. I will poke around in CCC tonight.
User avatar
Greg2600
Posts: 118
Joined: Fri Feb 22, 2013 12:43 am
Location: New Jersey
Contact:

Re: Connecting a PC to a CRT TV via composite

Post by Greg2600 »

energizerfellow‌ wrote:
Greg2600 wrote:I found an old Monoprice VGA to Component (YPbPr) Converter but after I got it realized the specs only output component over 480p/720p/1080i which is too high for the CRT.
I'll bet money on it working perfectly at 15khz 240p/480i if it doesn't have an internal scaler. It won't "officially" support 15 khz as they probably never bothered to test the VGA input at anything under 31 khz.
I'm afraid you'd lose that bet as I did, because it does not. Basically I get B&W image that's doubled.
nmalinoski wrote:
Greg2600 wrote:What's the best way to convert VGA (say Dreamcast or Laptop) to Component 480i/240p on CRT TV? I found an old Monoprice VGA to Component (YPbPr) Converter but after I got it realized the specs only output component over 480p/720p/1080i which is too high for the CRT.
Some laptops should be able to natively output composite and S-Video. If yours can't, you could use something like a Corio2 to downscale to 480i or 240p.

If you're simply transcoding RGB to YPbPr, like in the case of the Dreamcast (Which is only RGBHV in 480p mode, otherwise RGBS or composite/YC for 480i/576i, all of which determined by the connected cable), then you have your choice between the Retrotek SCBV1P3 (RGBS/SCART->YPbPr/RCA; limited to 480i/576i), the Retrotek VGACTV1 (RGBHV/VGA to YPbPr/RCA, does at least 1080i), linuxbot3000's transcoder (RGBHV/VGA to YPbPr/RCA, unsure of limitations), or the ShinyBow SB-2840 (RGBS/SCART to YPbPr/RCA, limited to 480p).

Personally, I'd handle each device separately. The Corio2 for downscaling output from the laptop; and I'd stick to a transcoder for the Dreamcast, since it does 240p/480i natively, and the transcoder shouldn't add any lag (so light gun games, yay).
Well my MAIN desire is to be able to use one device that accepts VGA and outputs component, because I have the DC, and the McWill modded Game Gear and Lynx which I want to use as well. Thanks for the suggestions, I'll see if any of those will work.
Classicgamer
Posts: 873
Joined: Thu Sep 11, 2014 3:37 pm

Re: Connecting a PC to a CRT TV via composite

Post by Classicgamer »

As an FYI, these vga breakout boards make it a lot easier to connect a PC to a jrok:

https://www.ebay.com/itm/Electronics-Sa ... SwakJcWbGv

Much easier than trying to figure out which wire connects to each pin if you cut a vga cable.
dreadnought
Posts: 53
Joined: Sun May 21, 2017 2:34 pm

Re: Connecting a PC to a CRT TV via composite

Post by dreadnought »

Bratwurst wrote:The RGB to NTSC/PAL board from TimeHarvest came in yesterday, it took me a bit of trial and error setting up Groovymame for the first time but I am super pleased to report that this thing works!
Thanks for the follow up :) Any further impressions?
User avatar
Bratwurst
Posts: 273
Joined: Mon Jul 31, 2017 3:09 am

Re: Connecting a PC to a CRT TV via composite

Post by Bratwurst »

dreadnought wrote:
Bratwurst wrote:The RGB to NTSC/PAL board from TimeHarvest came in yesterday, it took me a bit of trial and error setting up Groovymame for the first time but I am super pleased to report that this thing works!
Thanks for the follow up :) Any further impressions?
I haven't had much time to do much further, but I will try to get around to some things soon:

My setup is a fresh Win7 64-bit build, 2400 Pro Radeon using Mame 203 with super resolutions. I wired a female VGA plug into the H-sync, V-Sync, RGB and ground inputs of the TimeHarvest board so I could just use a standard VGA cable without cutting it up.

As I mentioned before, anything with a deep blue color appears fuzzy/poorly defined (such as the blue text on black in Battle Circuit's bootup). Overall image doesn't seem as sharp as it could be with s-video, and when I try to adjust vertical position within Mame I don't see the movement incrementally between lines like I would using an Extron Emotia. I did attempt adjusting the color pots thinking perhaps blue is just overwhelming everything else but didn't get very far. I didn't really get the chance to play much with that.

I was able to appreciably compare composite and s-video switching between two inputs on the fly and you're going to want to stick with s-video if possible. Composite's just not that great, noticeable artifacting.

The upside is that the frequency / framerate is proper, for example I observed no horizontal clipping with the yellow scrolling text for the intro of Turtles in Time like I would with the Emotia. Setting up 60hz or 15hz within Emu Driver's menu seemed to make no difference.

I would like to hook up my Super Famicom to the RGBSync inputs and compare the Time Harvest s-video to the s-video output of the Super Famicom itself, that's next on the list.

I'm also wondering if going with a WinXp 32-bit setup would yield better results without those super resolutions. That is to say, displaying the games in native res instead.

Here is a close picture of the board if anyone would like to dissect it: https://i.imgur.com/0M3QpoR.jpg

IC1 is BH7236AF. IC2 & IC3 are 74HC86D. XT1 is NTSC standard 3.5795 Mhz crystal.
User avatar
Bratwurst
Posts: 273
Joined: Mon Jul 31, 2017 3:09 am

Re: Connecting a PC to a CRT TV via composite

Post by Bratwurst »

Sorry to dredge up a somewhat stale thread but I gotta update my experience with this RGB to S-Vid/Composite board from Timeharvest. It's friggen great.

Went with a new build of Groovymame/CRT Emudriver: Windows XP 32-bit, Mame v.152, Radeon X600 card. Basically, Magic Resolutions instead of the Super Resolutions of Windows 7. The pixels match up way better with the scanlines of the television now, but initially I was dismayed because the colors were so saturated that it was difficult to wring good contrast out of the image by playing with the adjustment pots on the Timeharvest board.

Then I dropped the color setting on my Sharp television from 30 (out of 50) all the way down to 1. If you go to zero, the image turns monochrome. But just barely enabling color brings everything to acceptable levels. No more fuzzy bloom on blues, red's not overwhelmig everything. I love it.

Sample pictures, my camera's not the best nor am I the greatest photographer in the world, but I'm extremely happy.

https://i.imgur.com/O9MmV63.jpg
https://i.imgur.com/Cp4YexB.jpg
https://i.imgur.com/s3aJGHM.jpg
dreadnought
Posts: 53
Joined: Sun May 21, 2017 2:34 pm

Re: Connecting a PC to a CRT TV via composite

Post by dreadnought »

Bratwurst wrote: Sample pictures,
Looks really good, I appreciate your reports. I'm living in Europe now, larging it up in with the SCART/RGB mode, but will definitely get one of these doodahs when back in Asia.
User avatar
Bratwurst
Posts: 273
Joined: Mon Jul 31, 2017 3:09 am

Re: Connecting a PC to a CRT TV via composite

Post by Bratwurst »

dreadnought wrote:Looks really good, I appreciate your reports. I'm living in Europe now, larging it up in with the SCART/RGB mode, but will definitely get one of these doodahs when back in Asia.
If you ever want a 3D printed enclosure for it, hit me up.

Image
Image
thchardcore
Posts: 481
Joined: Wed Jun 22, 2005 9:20 am
Location: Liberal cesspool

Re: Connecting a PC to a CRT TV via composite

Post by thchardcore »

Oh! I do want a case for mine. PMed
A camel is a horse designed by a committee
thchardcore
Posts: 481
Joined: Wed Jun 22, 2005 9:20 am
Location: Liberal cesspool

Re: Connecting a PC to a CRT TV via composite

Post by thchardcore »

Bratwurst is a very very nice person! Wish everyone was as nice as this.
A camel is a horse designed by a committee
Post Reply