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 Post subject: Cable Guru's... How and where to ground all that shielding?
PostPosted: Wed Aug 09, 2017 12:20 pm 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
Dear people,

Maybe this has been asked before but I could not find it clearly in the forums so here goes...

I am in the process of creating my own individually shielded scart cables for all of my consoles and was wondering if there is a defenitive way of how to ground all the shielding? I read things about connecting it to ground in both ends of the cable, and I read things about only connecting it to ground on the console side. What is the correct way, and why?

I also try to seperate audio and video shielding as much as I can (this is the correct way I believe?), which is not always easy considering the thickness of the cable and the small size of some plugs. The saturn 10 pin mini din was a real challenge. For those interested I added some pictures below to see what cable I am working with.

Hope someone can shed some light on this.

Thanks!

Image

Image


Last edited by unstablewarpfield on Thu Aug 10, 2017 10:04 am, edited 1 time in total.

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 Post subject: Re: Grounding the shield of individually shielded RGB cables
PostPosted: Thu Aug 10, 2017 10:03 am 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
Ok... I think I have figured it out myself. I guess to avoid ground loops it is best to ground the shielding of the rgb and audio lines only on one side? Still remains... which side will it be? Console side or scart side? If it doesnt matter... Scart side is easier soldering in most cases.

Any ideas?


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 10:31 am 


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Joined: 28 Feb 2015
Posts: 311
Location: Rome
You should ground on both sides and, if using an external sound system, separate audio and video grounds to avoid interferences.

This is how I've made all my own cables and never had an issue.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 10:37 am 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
Allright, this is what I have done in the cables for my saturn, jaguar, mega drive and N64. I use an external sound system, but it takes the sound from the headphones out of the tv, so sound is handled bij the tv. Still... I don't think it can hurt to use seperate audio and video grounds. I'll keep on doing that. Unless somebody else has something to say about this I will continue completing my setup in this way :-)


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 11:50 am 


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Joined: 28 Feb 2015
Posts: 311
Location: Rome
If you're using an external sound system there's no need to route the audio through the scart.

Grab the left, right and audio ground from the cable and instead of soldering them on the SCART connector, solder a female 3,5mm/6,2mm/RCA jack and connect it straight to your sound system. The audio clarity will benefit from this.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 11:51 am 


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Joined: 26 Aug 2016
Posts: 28
It would be nice if you would make some kind of wiring schematic for the rest of us. :)


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 2:35 pm 


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Joined: 28 Feb 2015
Posts: 311
Location: Rome
Uhm, there's no rocket science behind making a cable.

Get the pinout of your console Audio/Video output, see which pin has what and connect it to the corresponding pin on the SCART connector.

Remember to connect all the grounds to the shield and there's not much else to do.

When in doubt, check this: http://members.optusnet.com.au/eviltim/ ... escart.htm


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 3:16 pm 



Joined: 07 Aug 2006
Posts: 424
Location: Sydney, Australia
unstablewarpfield,

The little din connectors are not designed to mate with thick, heavy duty, shielded cable. If you want to use cable like this, a practical way is to use a short thinner cable soldered to the connector which goes into a junction box where the thicker cables is connected. The HD Retrovision cables work like this.

It is important to connect ground wires at both end (this is not a guitar lead). You can used multiple wires for ground inside the cable too. It's normally impossible to make a ground loop with a game console unless you somehow hook your controller to your TV or something odd like that.

The AV socket on my own Saturn is a bit corroded/worn and doesn't make a perfect connection to the A/V plug ground (maybe an ohm of resistance). As a result, even with perfect cables I still get some buzzing in the audio.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Thu Aug 10, 2017 11:53 pm 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
donluca wrote:
If you're using an external sound system there's no need to route the audio through the scart.

Grab the left, right and audio ground from the cable and instead of soldering them on the SCART connector, solder a female 3,5mm/6,2mm/RCA jack and connect it straight to your sound system. The audio clarity will benefit from this.


Actually.. for me the reason to route my audio through scart is that I have 16 consoles using scart. I did not feel like getting another switcher for a seperate audio signal. Easier was to just have one cable from my tv to the audio system and have my switcher handle video and audio. I don't really notice any degraded sound or any buzzing/humming/hissing. That... and with the cable thickness I am using it is pretty hard to add a breakout cable for audio :-p


Last edited by unstablewarpfield on Fri Aug 11, 2017 12:10 am, edited 1 time in total.

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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 12:10 am 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
viletim wrote:
unstablewarpfield,

The little din connectors are not designed to mate with thick, heavy duty, shielded cable. If you want to use cable like this, a practical way is to use a short thinner cable soldered to the connector which goes into a junction box where the thicker cables is connected. The HD Retrovision cables work like this.

It is important to connect ground wires at both end (this is not a guitar lead). You can used multiple wires for ground inside the cable too. It's normally impossible to make a ground loop with a game console unless you somehow hook your controller to your TV or something odd like that.

The AV socket on my own Saturn is a bit corroded/worn and doesn't make a perfect connection to the A/V plug ground (maybe an ohm of resistance). As a result, even with perfect cables I still get some buzzing in the audio.


Yeah... I kinda noticed that the mini dins are not easy on this type of cable. So much even that I was dremeling parts of the back shell away. The 10 pin mini din came with a chassis that was simply not useable so I took the back shell of a 9 pin mini din. That worked. Unfortunately I had to resort to epoxy to get any form of strain relief on the plug. It was the only way. I did thesame for the snes cable and the atari jaguar (another nasty connector to source) that I made. They turned out really well and give me exellent image and no audible buzz whatsoever.

Thanks for the clear answer. I shall ground both sides of my shielded cables and will keep on working like that until I finish all of my cables. Think I'll do some consoles that I modded with a normal din out and my cd-i with scart out next. Those are a bit easier than the mini dins or proprietary connectors :-)

Here are a couple of pics of the cables I made. All of them required epoxy to glue parts together. I did not trust hotglue to do that job.

Image

Image

Image


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 11:59 am 


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Joined: 28 Feb 2015
Posts: 311
Location: Rome
unstablewarpfield wrote:
Actually.. for me the reason to route my audio through scart is that I have 16 consoles using scart. I did not feel like getting another switcher for a seperate audio signal. Easier was to just have one cable from my tv to the audio system and have my switcher handle video and audio. I don't really notice any degraded sound or any buzzing/humming/hissing. That... and with the cable thickness I am using it is pretty hard to add a breakout cable for audio :-p



Oh I see, then that makes perfect sense, for the sake of convenience ;)


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 4:33 pm 


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Joined: 03 Jul 2014
Posts: 27
unstablewarpfield wrote:
Here are a couple of pics of the cables I made. All of them required epoxy to glue parts together. I did not trust hotglue to do that job.


Clean looking cables.

Where did you get your female scart connector?


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 5:01 pm 



Joined: 14 Mar 2011
Posts: 70
Location: Sacramento, CA
I agree those are very clean and heavy duty looking cables...

How is the audio/video isolation during bright scenes?


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 5:20 pm 


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Joined: 25 Dec 2013
Posts: 231
Location: Indiana
thebeautifulones wrote:
unstablewarpfield wrote:
Here are a couple of pics of the cables I made. All of them required epoxy to glue parts together. I did not trust hotglue to do that job.


Clean looking cables.

Where did you get your female scart connector?


That appears to be a jaguar connector.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 6:15 pm 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
Thanks for the comments :-)

That is not a female scart. It is a connector for my jaguar. The problem is that you dont see these types of edge connectors with a shell around them. At least... not that I could find. I sourced these two seperate parts on one of the major electronic sites on the web (not sure if I can mention them here) and selected them to be the closest match possible. Then with the help of some epoxy I glued the connector in the shell. Works perfect. (If you look closely you can see the connector is just a bit off. That's what happens when your clamps slip halfway during the curing process :( No problems though. It still fits in the console.) Disadvantage? When anything happens to that cable there is no way on earth I am going to crack that connector open without damaging it. I'll take my chances though since all my cables will almost never be removed from my consoles.

One of the first things I did was testing a white screen, since before it gave me trouble on that. Now... nothing! When I listen super super carefully I can hear the faintest hint of a hiss, but I hear that also with my whole video system turned off so that must be the quality of my 1996 phillips stereo as a sound amplifier :P Running some brighter scenes does not change a thing in the audio. I guess I am on the right track here :-)


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 7:28 pm 


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Joined: 03 Jul 2014
Posts: 27
citrus3000psi wrote:
thebeautifulones wrote:
unstablewarpfield wrote:
Here are a couple of pics of the cables I made. All of them required epoxy to glue parts together. I did not trust hotglue to do that job.


Clean looking cables.

Where did you get your female scart connector?


That appears to be a jaguar connector.

Oh yeah, you're right. When I thought it was a scart connector I liked that it was straight instead of angled.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 7:30 pm 


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Joined: 03 Jul 2014
Posts: 27
unstablewarpfield wrote:
Thanks for the comments :-)

That is not a female scart. It is a connector for my jaguar. The problem is that you dont see these types of edge connectors with a shell around them. At least... not that I could find. I sourced these two seperate parts on one of the major electronic sites on the web (not sure if I can mention them here) and selected them to be the closest match possible.

What was the shell originally intended for?


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 8:02 pm 



Joined: 14 Mar 2011
Posts: 70
Location: Sacramento, CA
unstablewarpfield wrote:
Thanks for the comments :-)

That is not a female scart. It is a connector for my jaguar. The problem is that you dont see these types of edge connectors with a shell around them. At least... not that I could find. I sourced these two seperate parts on one of the major electronic sites on the web (not sure if I can mention them here) and selected them to be the closest match possible. Then with the help of some epoxy I glued the connector in the shell. Works perfect. (If you look closely you can see the connector is just a bit off. That's what happens when your clamps slip halfway during the curing process :( No problems though. It still fits in the console.) Disadvantage? When anything happens to that cable there is no way on earth I am going to crack that connector open without damaging it. I'll take my chances though since all my cables will almost never be removed from my consoles.

One of the first things I did was testing a white screen, since before it gave me trouble on that. Now... nothing! When I listen super super carefully I can hear the faintest hint of a hiss, but I hear that also with my whole video system turned off so that must be the quality of my 1996 phillips stereo as a sound amplifier :P Running some brighter scenes does not change a thing in the audio. I guess I am on the right track here :-)


How easy are these cables to produce? Do you mind sending me a test cable for SNES? I would like the test out the isolation myself. Having a source of high quality SCART cables to refer people to would go great with my next project.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Fri Aug 11, 2017 9:47 pm 



Joined: 02 Sep 2012
Posts: 22
Fusion916 wrote:
unstablewarpfield wrote:
Thanks for the comments :-)

That is not a female scart. It is a connector for my jaguar. The problem is that you dont see these types of edge connectors with a shell around them. At least... not that I could find. I sourced these two seperate parts on one of the major electronic sites on the web (not sure if I can mention them here) and selected them to be the closest match possible. Then with the help of some epoxy I glued the connector in the shell. Works perfect. (If you look closely you can see the connector is just a bit off. That's what happens when your clamps slip halfway during the curing process :( No problems though. It still fits in the console.) Disadvantage? When anything happens to that cable there is no way on earth I am going to crack that connector open without damaging it. I'll take my chances though since all my cables will almost never be removed from my consoles.

One of the first things I did was testing a white screen, since before it gave me trouble on that. Now... nothing! When I listen super super carefully I can hear the faintest hint of a hiss, but I hear that also with my whole video system turned off so that must be the quality of my 1996 phillips stereo as a sound amplifier :P Running some brighter scenes does not change a thing in the audio. I guess I am on the right track here :-)


How easy are these cables to produce? Do you mind sending me a test cable for SNES? I would like the test out the isolation myself. Having a source of high quality SCART cables to refer people to would go great with my next project.


Adding to that theme.

Does anyone know, or have any suggestions for, a suitable shielded cable for making SCART cables that could be bought in USA?

I looked up the cable that unstablewarpfield uses and it looks awesome but it also seems to be Europe only, understandably.


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 Post subject: Re: Cable Guru's... How and where to ground all that shieldi
PostPosted: Sat Aug 12, 2017 9:48 am 



Joined: 30 Jun 2017
Posts: 9
Location: The Netherlands
Wow... I didn't expect this haha. My intention was not to fabricate these cables for distribution. People have asked me this before though. Time-wise it is just not worth it (I don't even think I have the time) Besides... It is a hassle to get the proprietary connectors since I scavenge them off of cheap cables. Even then the connectors might be unusable since many times the cheaper cables are AV and for some reason they choose to cut back on the amount of pins inside these connectors. After ordering two failed ps1 cables I have learned to ask the seller first to check up on all the pins inside the connector :P

As to the where, how and what regarding the jaguar connector... I don't know if I am allowed to link it here, but down below are the parts I used. I like using this website since it has no shipping costs and with small cheaper parts that is extremely welcome :-) You can check out the dimensions in the schematics to see how close a fit they are. I remember the strain relief was really nice on this perticular shell.

Edge connector
Back shell

I can recommend to check this website for the more unconventional parts if you need them but the real electronics wizzards on here will probably already know their sources :-)

For example, I managed to find on there the expansion connector for the amiga cd32 so I made a quick and dirty rgb adapter board. Perfect image :-D
Image
Image


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