Where to buy your RGB cables and what to look for

[Lawfer]

All of my cables are Official.

Friend sent me a Neo Geo AES to fix. Turns out the cable he had bought from retrogamingcables was defective. I wouldn't buy from them myself.

Robert of RetroGamingCables is a stand up guy, if there is a problem just email him.

Well, Robert should just shield his cables, and quit just saying "it doesn't need it!". Give in to your customers pleas, Rob.

I only used his cables for RGBS, not audio. Doesnt shielding and filtering pretty much just make sense for digital LCDs/LEDS/OLEDS etc. and not CRTS?

[Ed Oscuro]

Doesnt shielding and filtering pretty much just make sense for digital LCDs/LEDS/OLEDS etc. and not CRTS?

No, these effects affect digital signals in the same way they do analog signals. It's just that many modern digital interfaces are high speed serial connections and therefore at least as susceptible to noise issues. This doesn't mean that bottom of the barrel components are good enough for 15KHz RGB, though.

[Lawfer]

This doesn't mean that bottom of the barrel components are good enough for 15KHz RGB, though.

Was that directed at retro gamong cables cables or sometghing else?

[Lawfer]

Some related links:
50 Ohm vs 75 Ohm: BNC Connectors Explained (MilesTek Blog) - One manufacturer's description of BNC plugs (we're interested in the 75 ohm type)
Component Video Cables -- A Guide (Blue Jeans Cable) - Mentions the effect of impedance in video.
Is there Really a True 75 Ohm RCA Plug?

I would recommand these:





Canare BCP-RCAJ certofied 75 Ohm

[bobrocks95]

Oh great, I'll be buying BNC male to RCA female adapters on Monday for my new plasma coming in, a conversion I thought would be dead simple. Now I need to worry about signal degradation over the incredibly short length of the adapter due to an impedance mis-match? Is this really a noticeable thing?

[Lawfer]

Oh great, I'll be buying BNC male to RCA female adapters on Monday for my new plasma coming in, a conversion I thought would be dead simple. Now I need to worry about signal degradation over the incredibly short length of the adapter due to an impedance mis-match? Is this really a noticeable thing?

Yes very much, but dont worry get this and you wont have to worry about any of that anymore:

http://www.bestbuy.com/site/audioquest- ... 8324437192

[evil_ash_xero]

I only used his cables for RGBS, not audio. Doesnt shielding and filtering pretty much just make sense for digital LCDs/LEDS/OLEDS etc. and not CRTS?

No, the cables of his that I had problems with, I was using on a CRT. Standard stuff. Turning up brightness causing a buzzing sound. That sort of typical cheap cable crap.
Also, sometimes it can cause interference with the picture (waves and whatnot).

I don't care, to a degree, since I am in the U.S., and can just buy my cables from RCA. But I feel bad for Europeans who would like their cables shipped a bit quicker.
I don't know what deal is with that guy. I mean, how much extra does it cost to shield?
And people bring it up to him, but he just won't budge.

If RCA could chime in, and let us know how much it actually costs to shield these cables, that would be informative.

[BuckoA51]

No, the cables of his that I had problems with, I was using on a CRT. Standard stuff. Turning up brightness causing a buzzing sound. That sort of typical cheap cable crap.

I've never encountered a SCART cable where that didn't happen to some degree or another.

[evil_ash_xero]

No, the cables of his that I had problems with, I was using on a CRT. Standard stuff. Turning up brightness causing a buzzing sound. That sort of typical cheap cable crap.

I've never encountered a SCART cable where that didn't happen to some degree or another.

Comparing my Genesis SCART cable from RCA and my other one from RGC, the difference is big enough to just chuck out the RGC.

I don't have some kind of vendetta against the guy. He should just shield his cables. ESPECIALLY with SCART, which is such an annoying cable to begin with.

If he would listen to his customers, and shield his cables, then I'd be like "here's a great option for people in the UK/EU". But he seems kind of hard headed.

[BuckoA51]

The pack a puched SCART I got from him has the least audio buzz of any Genesis cable I've tested.

I'm in contact with him fairly regularly though and I'll pass that along. I'm actually expecting one of his new design SNES cables in for review so I'll post full pictures when I get it.

[evil_ash_xero]

If you are in contact with him regularly, hammer on him that people want shielded cables.

Why do you think RCA is so popular, and well regarded?

[Xan]

Regardless of what others say, I'd certainly appreciate if he'd overthink his choice of capacitors. Even if it's just a cable, using reputable brand caps as opposed to generic stuff simply eliminates one possible cause of failure.

[BazookaBen]

Does shielding help cut back on ringing and ghosting? I ask because I made custom RGB leads for my systems, which consist of about 8cm of unshielded wire that ends in in a VGA lead, to which I then attach a shielded 4 BNC cable. Wondering if that short distance without shielding is causing the ghosting I get on bright, uniform backgrounds.

[jskyboo]

Some related links:
50 Ohm vs 75 Ohm: BNC Connectors Explained (MilesTek Blog) - One manufacturer's description of BNC plugs (we're interested in the 75 ohm type)
Component Video Cables -- A Guide (Blue Jeans Cable) - Mentions the effect of impedance in video.
Is there Really a True 75 Ohm RCA Plug?

I would recommand these:





Canare BCP-RCAJ certofied 75 Ohm

Where can you find these?

[bobrocks95]

Does shielding help cut back on ringing and ghosting? I ask because I made custom RGB leads for my systems, which consist of about 8cm of unshielded wire that ends in in a VGA lead, to which I then attach a shielded 4 BNC cable. Wondering if that short distance without shielding is causing the ghosting I get on bright, uniform backgrounds.

I noticed an awful lot of ghosting when I hooked my Genesis (using an unshielded SCART cable) into my plasma. It's not really visible on my CRT though. My shielded SNES cables don't show the same ghosting effects.

[BuckoA51]

Can I sheild an unshielded cable myself just by wrapping some electricians tape around the connections?

[Ed Oscuro]

Ahh, and I'm the one going crazy...well, if people follow up on these questions, in short order we should have some better information to fill in the blanks!

Now I need to worry about signal degradation over the incredibly short length of the adapter due to an impedance mis-match? Is this really a noticeable thing?

https://en.wikipedia.org/wiki/BNC_conne ... 75_Ohm.jpg

Despite the picture, they should work together. 75 ohm is most common in this area and probably what you'll find for video.

I'd only be mildly interested in the problem if somebody had mixed 50 and 75 ohm plugs / terminators on one cable. It might not cause any problem even then.

Can I sheild an unshielded cable myself just by wrapping some electricians tape around the connections?

I don't think it'd do anything (not shielding / conducive), but see what happens...if you really want to get serious, put some tinfoil around each wire first I suppose you could conduct an experiment using some of this stuff, but I doubt it'll matter.

[HydrogLox]

Does shielding help cut back on ringing and ghosting? ... Wondering if that short distance without shielding is causing the ghosting I get on bright, uniform backgrounds.

In practice one would not expect these types of issues over a short run of cable - that being said it is conceivable that in your particular case you may have a "Perfect Storm" happening. Wire Crosstalk:

• Any analog (or digital) signal carries information by the means of variation of voltage (and current) over the conductor.
• That variation/signal also leads to a varying electromagnetic field around the conductor carrying the signal.
• Micro-currents are induced when that changing electromagnetic field intersects with an adjacent conductor.
• Those micro-currents ultimately interfere with the signal that is on that adjacent conductor.

Now in practice all you have to do is to reduce the efficiency of the energy transfer between both conductors to reduce crosstalk. That is the basis of the unshielded twisted pair - the wires are never parallel so the respective em-fields are never at an optimal angle for energy transfer (this ever-changing angle also helps when moving through an external em-field).

Now it could be that in your case the R,G,B conductors are straight, parallel and adjacent in the cable bundle. When there is a "bright, uniform background" at least one of them will have a particularly strong signal (i.e. maximum variance) associated with a strong em-field that induces micro-currents in the adjacent conductors resulting in "ringing and ghosting".

Typically interference is expected on longer runs of unshielded cable simply because without countermeasures there is more amble opportunity for crosstalk or interference from outside sources (e.g. acting like antenna for noise from a microwave oven or vacuum cleaner).

See also: TV Scart Cable Crosstalk Interference Causes, Scart Lead Problems

A shield (or screen) is simply a separate conductor that surrounds the conductor that carries the signal - the shield is a Faraday cage that the em-field can't pass though - typically the shield is grounded on the source end to dissipate any micro-currents. In order to protect against crosstalk each individual signal carrying conductor must have its own shield. A single shield around the cable bundle protects against external em interference but not crosstalk as all the signal conductors are within the same Faraday cage.

[BazookaBen]

I guess a way to test that would be to put foil between the wires? I'm sure I would notice some sort of change if that short unshielded part is causing my ghosting.

[ApolloBoy]

Can I sheild an unshielded cable myself just by wrapping some electricians tape around the connections?

LOL what?

[evil_ash_xero]

Can I sheild an unshielded cable myself just by wrapping some electricians tape around the connections?

LOL what?

Well, what if he put an actual shield on it. Like a nice one, with a coat of arms?

[Ed Oscuro]

I'm afraid electrician's tape isn't mentioned in the official heraldic handbooks. Gaffer's tape might be acceptable though. Duct tape is definitely out.

https://en.wikipedia.org/wiki/Speed_tap ... d_tape.jpg

[BuckoA51]

Well we are in the realms of audiophile/videophile black magic here. Electricians tape is insulating after all, not everyone has a good understanding of electronics on here, that's why I asked.

So which bits are the shielding on this cable then?

ps-luma by videogameperfection, on Flickr

[RGB32E]

Well we are in the realms of audiophile/videophile black magic here. Electricians tape is insulating after all, not everyone has a good understanding of electronics on here, that's why I asked.

So which bits are the shielding on this cable then?

ps-luma by videogameperfection, on Flickr

There's a drain wire that is connected to ground which runs along the outer shielding of the cable. For some reason the tubing was never shrunk on this cable?!

[BuckoA51]

OK, that's what I thought.

I don't however see any shielding on any other of the wires? Nobody has given me a satisfactory answer to the question of exactly which wires supposedly need this extra shielding and which don't??

Here's a cable from retro computer shack for comparison.

retro-computer-shak-spectrum-scart by videogameperfection, on Flickr

Looks like he's shielded the grounds and the RGB.

[RGB32E]

OK, that's what I thought.

I don't however see any shielding on any other of the wires? Nobody has given me a satisfactory answer to the question of exactly which wires supposedly need this extra shielding and which don't??

The RCA cable you first shared has overall shielding - all of the conductors are surrounded by the same outer/overall shield. Here's a general illustration of multi-conductor cable with an overall double shield (foil plus braid):

Here's a cable from retro computer shack for comparison.

retro-computer-shak-spectrum-scart by videogameperfection, on Flickr

Looks like he's shielded the grounds and the RGB.

The RCS cable doesn't appear to be shielded from the picture angle. Is there any foil and/or braid around the conductors (underneath the outer jacket)?

The tubing around 4 of the pins is just tubing. Typically used as a strain-relief of sorts to avoid conductors from breaking off. The smaller the conductor the more likelihood of breakage. It looks like the tubing over pin 16 also contains a resistor.

If you want to see what individually shielded conductors looks like:

A "double shielded" cable - 6 mini coax, 1 single conductor for +5VDC, overall braided shield, and drain wire (continuity with outer shield).

[BuckoA51]

Super helpful post RGB32E, thank you. Clearly I have been mistaking the tubing stuff for shielding. Yes, feel free to post insults.

No, there's no foil/braid around the conductors on the RCS cable, though to be fair it seems to work well.

Now at least I know what to look for when reviewing cables.

[HydrogLox]

I guess a way to test that would be to put foil between the wires? I'm sure I would notice some sort of change if that short unshielded part is causing my ghosting.

For the shielding to be effective it has to at least approximate a "hollow conductor" surrounding the insulated wire it is supposed to be screening. Improvising with kitchen aluminium foil you face at least two challenges:

• Ensuring that both sides of the foil have good electrical contact to form the hollow conductor (the faraday cage) - even when overlapping foil portions touch, good electric contact isn't always guaranteed.
• Attaching the drain wire to the foil - again with good electrical contact (FYI in the long run untreated copper to aluminium contacts will corrode).

If you are simply looking for a quick and dirty test and your wires aren't encased in a cable jacket then simply spread the signal wires out, possibly aided by some short pieces from a drinking straw or the like. While that may not entirely eliminate any crosstalk, it should at least reduce it as the wires are no longer running straight, close and parallel.

Nobody has given me a satisfactory answer to the question of exactly which wires supposedly need this extra shielding and which don't??

The problem is that the answer typically is - "it depends". Under some circumstances you don't need any shielding. If you want to counter interference from outside of the cable then a single shield around the cable bundle is sufficient - but that won't counter crosstalk between the wires inside the cable. Crosstalk might not be an issue, the wire insulation between the conductors may provide sufficient physical separation or the wires don't run straight and parallel inside the cable jacket. But if you want to counter crosstalk, individual wires will each need their own shield. DC power and ground conductors shouldn't need to be shielded inside of a cable shield - unless the power and ground are extremely noisy ...

In many cases individually screened wires are overkill - but if you want full coverage you'll have to pay the premium.

See http://www.conrad-electronic.co.uk/ce/e ... aus-Conrad
for some ways network cables are shielded. Now here no example actually shields a single wire because the "twisted pair" is already a common crosstalk countermeasure.

[Ed Oscuro]

For the shielding to be effective it has to at least approximate a "hollow conductor"

Note also that a conductor is not an insulator. Hence the dismissal of electrician's tape.

[RGB32E]

Where can you find these?

http://syntex.sk/p/bcj-rcap/c/connectors?lang=EN