Maybe you've got a few HD devices around and only one component video input on your HDTV. We've even got component out on our dear old laserdisc player. So we were rooting around in our box of parts and realized that we could make our own component video switch. HDTV switches are ungodly expensive, but KVM have gotten dirt cheap; in today's How-to we'll show you how to turn one into a component video switch.
Today's How-To is pretty easy. We'll have to make some component to VGA cables up, and trick the switch into thinking that there's a computer on each input. Our inspiration came from the
VGA from Cat5 writeup. We decided to extend the simple VGA to component video converter idea into our DIY component video switch. The mod should work as long as the switch doesn't do ANY video processing. You can also use the setup to switch between VGA and component input sources - but it will only work outputting component video. The VGA to component trick combines some signals to work, they can't be easily split apart to turn component back into a VGA signal.
Before all the videophiles freak out about the cables, this was built as a proof of concept. A better build would use quality cable components, etc. Feel free to point out your favorite high quality cable components in the comments.
The concept is simple. We'll build some RCA component to HD15 VGA cables for inputs and a HD15 to component cable for the output. We know that the Cybex can switch between VGA video sources. The premise behind our build depends on the Cybex passing component video signals in place of the VGA. Since it doesn't do any processing, it doesn't care what it's passing through.
We only need some basic tools for today's How-To. Wire strippers, soldering iron, cutters and a sharp knife. Oh, and grab a multi-meter with continuity testing. Most digital meters include one that beeps when they sense a completed circuit.
We'll have to add a 5 volt power source and some jumper wires to the keyboard connectors to make each input line active for the Cybex to switch to it. Our switch uses male HD15 D-Sub connectors for each input.
When a source is available the Cybex indicates it by lighting up the bottom LED. In reality, it looks for 5 volts on the keyboard connector. We need to trick it into thinking that our component sources are available. We could chop some keyboard connectors or we can do a little soldering.
Opening the case is easy, we just remove two screws from the bottom.
To get the Cybex to think that there's a source, we need to supply 5 volts to this pin. We can steal 5 volts from the power input or supply it from a keyboard port. It's up to you. Just jumper 5v to this pin of the keyboard connector for each input you want to use.
For our build we dug up some cheap male to male cables. We'll cut each one in half. For three inputs and an output, two cables will suffice.
This is why the cable geeks will hate this. We used some $.49 rca cables from
Parts Express to make our component ends. They're dirt cheap, and perfect for our test build.
Grab your knife and carefully slit the outside sheath. If you go too deep, you'll cut some of the wires you need.
Strip each of the leads so we can identify the wires we'll need.
Grab your meter and identify the wires you need. A helper or a set of alligator clips will make the job much easier. Check out the
VGA pinout at pinouts.ru and the component to VGA adapter pinout at the
VGA over Cat5 writeup. (We've simply used the colors of the normal connectors to designate the wires below.)
Simple VGA to RGB pinout:
- HD15 pin1 -- Red Signal
- HD15 pin 6 -- Red Shield
- HD15 pin 2 -- Green
- HD15 pin 7 -- Green Shield
- HD15 pin 3 -- Blue Signal
- HD15 pin 8 -- Blue Ground
Once you've identifed your wires, you can get soldering. We used our alligator clip helping hands to hold things steady. Before soldering each one, we double checked the pin outs with our meter.
As we soldered each pair, we marked the connectors with a Sharpie.
After everything is built, all of the connections need to be insulated. For a permanent build, we prefer heat shrink tubing. For our test setup, we grabbed the electrical tape and got busy.
That's it. They Cybex is modified, and the cables are built. Oh, and it worked. Enjoy your new found component switching freedom!
By the way: you can buy a commercial video switch for about $100, so keep an eye on what you spend building this project. We had all the parts in our junk box, so it only cost a few inches of solder and some crappy cables. (And we just had to try it.) Double check EVERYTHING before hooking it up, and you should be just fine. If you'd like this to be remote controlled, a PIC controller could be built to recieve IR commands and either input the keyboard shortcuts or simulate button presses. Let us know if you build your own!
posted Sep 5th 2006 at 7:15PM
Reader Comments (Page 1 of 1)
c @ Jun 5th 2008 12:49AM
HD15 TO component is this the same for AV red white & yellow
c @ Jun 5th 2008 5:20PM
ok i now know there is no auido from HD15 so can all the video be put to one RCA say yellow
jeh @ Jun 13th 2008 5:39PM
> video is 75ohm, audio is 110ohm... keep this in mind when modding
Video is indeed 75 ohm impedance (not "resistance"!). But analog audio runs in "bridged" mode, with source impedance 600 ohms or less (sometimes as low as 100 ohms) and load impedance 10K. This is not an "impedance mismatch", it's supposed to be that way.
A VGA KVM switch should (if it's designed well) present a 75 ohm impedance (since this impedance is used in the VGA connections as well as in component video).
Digital audio over coax to an RCA connector (SPDIF, now called IEC 958) is 75 ohms and can use the same RG59 cables as component video. If you have an XLR jack for digital audio you are then dealing with 110 ohms (AES/EBU
A cheap passive switch as some are recommending here is almost certainly NOT 75 ohms.
Using Y-adapters to combine signals of almost any sort is an absolutely TERRIBLE idea. The impedances will be all wrong. Even for analog audio, let alone video.
Here's an idea: Any VGA KVM switch is also switching the H and V sync lines... and it shouldn't alter those signals any more than it should alter the R G and B signals. So it ought to be possible to run digital audio through one of those (the impedance will even be correct), or analog audio through both of them (the impedance won't matter). I'm going to try it.
Matthew Castillo @ Sep 5th 2006 7:24PM
o.O It works! That's very kewl. I've been wondering how I could remedy my lack of component-in issue for a long while. Nice to see a good DIY, but engadget always does provide :)
Brett @ Mar 29th 2007 11:22PM
So, I can use that hook up to Have my Xbox connected to my monitor via Component>VGA, right?
James @ Sep 5th 2006 7:33PM
Why would you go though all this trouble? Is $20 too much for a manual component switcher? If it is go pick up a regular video switcher with audio and video RCA jacks and use the 3 for for component instead of Video/Audio. $10 problem solved.
Scoobydoo @ Sep 5th 2006 7:36PM
This does seem kind of silly, places like Monoprice sell a manual VGA switch for under $10. Why anyone would rip open a Cybex to do this is beyond me...
Edward @ Sep 5th 2006 7:41PM
i was literally wondering where to buy one of these this morning. you guys seriously just made my freaking day
TVGenius @ Sep 6th 2006 10:15AM
Crap. Save all the soldering and just buy three RCA Y-adapters... when you want Xbox, turn DVD player off. When you want DVD, turn Xbox off.
J1000 @ Sep 5th 2006 8:04PM
FYI, if you don't mind RCA audio, MadCatz (yes, MadCatz) makes an excellent component switch. It allows 4 sources, has a corded switch box with suction cups, and only costs about $30. It's hard to find though.
Adam @ Sep 6th 2006 4:36AM
Here's an idea... buy a reciever... it will do all of of this for you, there will be no signal loss and its alot easier..
Adam @ Jan 17th 2007 7:39AM
Come on now, of course there is signal loss - even on very high end receivers with very nice cables. I used to work at a very high end audio shop - when showing off 1080p televisions we would never connect the video cables through the receiver. We actually used picture in picture to show the difference, it was noticable enough to make you want to hook up all your high definition devices straight to the back of the television
J1000 @ Sep 5th 2006 8:07PM
Aha! Found a link. Here's the Madcatz component switch I use, and these guys are selling it for $10!
http://www.amazon.com/Madcatz-Universal-Game-System-Selector/dp/B00002CETC/ref=sr_11_1/103-1788475-5323065?ie=UTF8
J1000 @ Sep 5th 2006 8:11PM
OOPS, that was the wrong Madcatz switch. It looks very similar. Here's the one I should have linked to. This one is $20. The only difference is it has 5 RCA jacks per source, as opposed to 3.
http://froogle.google.com/froogle_cluster?q=madcatz+component+switch&btnG=Search+Froogle&lmode=online&oid=13059901895379698553
SHEiK124 @ Sep 5th 2006 8:20PM
Forgot even buying a special component switch! A normal RCA switcher (composite + L/R audio) should work fine...
scenestar @ Sep 5th 2006 8:54PM
I was pissed to see this cause i just ordered one but that does look like a lot of work. search ybpbr on lik-sang.
murphy @ Sep 5th 2006 8:27PM
For 1080i you really need a switch with at least 30Mhz (-3db) of bandwidth - 50Mhz or more would be ideal. That will ensure minimal loss of signal.
Since the bulk of the signal is in the Y portion of the image a lower bandwidth component would result in a less sharp image, especially around high frequency areas (lines, edges, etc).
If you don't care about a degredation of image quality or have a really small screen you can save a few bucks by purchasing a cheaper switch. But then, why would you waste thousands of dollards on an HDTV in the first place?
Here are a few examples of higher bandwidth components:
http://www.ramelectronics.net/html/40-814.html
http://www.pccables.com/02450.htm
http://www.digitalconnection.com/Products/Video/1154A.asp
blurry @ Sep 5th 2006 8:27PM
I used a simple RCA switch I picked up for less than $20 -- it was originally meant for L/R analog audio and 1 video per input -- so instead it is now a 4x1 component video switch. Think about it, component video is analog so therefore anything that can switch analog can work, when it comes right down to it.
Seriously, get one of these switches and paint the yellow and white rca inputs to blue and green and sell it on eBay for double its price with the fancy "Component Video" label on it. The idiocracy we live in is madness! You people will buy anything if it's rebranded well enough!
kalmbach @ Sep 5th 2006 9:04PM
Just a small warning for you people deciding to go with the composite+L/R swith:
I've come to notice that audio and video cables sometimes (always should?) have different resistance. This would result in a difference in resistance between the three separate signals carried in your component cable. You could then get different results depending on which two cables you decide to run through the audio L/R switch.
Sorry to say, I never tried this out myself. But in theory the could be problems.
kalmbach
Peter @ Sep 5th 2006 9:16PM
Those of you who think you can buy a $10 composite switch need to read murphy's post. There is MUCH more to video switching than just making the physical connections. Any timing differences in the signal caused by mismatched cables, differing cable lengths, poor connections or anything else will manifest themselves in a poorer quality image. You will see artifacting, ghosting, color shifts and other anomalies.
And as murphy said, if you spent all that money for an HD setup, spend the extra money and get a good quality switcher.
doug @ Sep 5th 2006 9:23PM
I got this one from GameStop. It was $20 and the last one in the store, so I nabbed it. I didn't even need it at that point, but I knew I would in the future.
http://www.gamestop.com/product.asp?product%5Fid=801888&Section=#PROD
jonnyep @ Sep 15th 2007 9:23PM
This is an S-Video / RF coaxial switcher, not for component video
Revenant @ Sep 6th 2006 9:13AM
Most RCA jack selector switches just switch the inputs from a -> b -> c and have very minimal internal wiring. They dont use any type of resistor or coils to change the resistance or impedance of the signal one way or the other. Same exact thing as moving the cables by hand. No difference whatsoever. Doesnt matter if they are component, composite, audio, data or whatever. The internals are usually not shielded (rf-wise) from each other on the cheap ones though. That is about the only difference between a $100 switch and a $10 radio-shack special. (I am a former "you got questions..." victim ...er employeee, so I know.) :P
MJ @ Sep 6th 2006 6:43AM
How about a guide of how to get the my PS2 connected to my computer monitor? Now that would be an awesome guide. I have no idea about this stuff, but I'm bookmarking in case I could use this somehow...
J1000 @ Sep 5th 2006 10:09PM
To the people who say to use a simple composite selector: the one obvious thing you've forgotten is sound. If you have a separate means of switching the sound channels (like two switch boxes) then great, otherwise get the 5-jack Madcatz one.
The cable quality concerns, as always, sound like a bunch of FUD to me. If I were viewing in 1080i I might be more critical (only a bit more), but most people aren't trying to do this. If people were trying to use coathangers in place of component cables then yeah, I see your point, but there's nothing wrong with your typical RCA cable set of a reasonable length.
Xenozx @ Sep 5th 2006 10:22PM
I have the Lik-sang component switch. It switches through 3 HD devices using the RED BLUE GREEN cables, pluse left and right audio cables. Its a manual switch, but has worked perfectly for many months, and I notice no difference in visual quality even at 1080I. Although I do have a 27 inch Picture tube HDTV, so I dont know what it would be like on a screen twice that size.
jonnyep @ Sep 15th 2007 9:23PM
Lik_Sang is out of business
Mike @ Sep 6th 2006 2:02AM
I'm using a cheap 2+1 switcher for my component and always have. I can plug my Xbox 360 into my 42" plasma with it - then without it - and it looks exactly the same. There is no timing issues, ghosting, or anything else funky about it. If there were I wouldn't use it. It works fine and costs $15.
Michael @ Sep 6th 2006 3:19AM
The video quality on this thing must be terrible... The KVM may be decent, but the cables are appalling.
betty @ Sep 6th 2006 4:07AM
component does not carry HD signals, only HDMI or DVI can do this.
jonnyep @ Sep 15th 2007 9:23PM
wrong
Mymac @ Sep 6th 2006 9:49AM
While you're at it. Would it be posible for you to make a how-to on "how-to make your own dvi/usb-kvm"? It would be really nice since most kvm's of that type costs too much for my budget
Arpad @ Sep 6th 2006 8:03AM
does anybody make a kvm with a remote control to switch between the devices? of course usb and audio is a must...
Adam: most receivers that switch component video will cost much more than this project does
ChickenSangwich @ Sep 6th 2006 8:34AM
RE:betty
component does not carry HD signals, only HDMI or DVI can do this.
Wrong. Component isn't digital like HDMI or DVI, but it is perfectly capable of carrying a HD signal, and has been for many years. FUD is on the march!!
slooth @ Sep 6th 2006 11:48AM
video is 75ohm, audio is 110ohm... keep this in mind when modding
slooth @ Sep 6th 2006 11:49AM
"component does not carry HD signals, only HDMI or DVI can do this."
not true, analogue HD is usually component.
Carson @ Sep 6th 2006 11:02AM
If folks want to do this, a much easier way to get the cables is to purchase VGA->BNC cables and some BNC->RCA adapters (unless you're lucky enough to have pro gear with BNC connectors)
schalliol @ Sep 7th 2006 7:33AM
Arpad, yes, there are IR KVMs out there.
For a component video switch for up to 8 ports and IR, you could probably use the IOGEAR 8 port VGA switch: http://www.iogear.com/main.php?loc=product&Item=GVS881 For a full KVM, others do exist.
I think I'm going to use a Kramer 8x8 VGA switcher to connect both VGA and component to a projector (Dell 2400MP) that accepts HD Component Video over a VGA connector (as well as VGA). After talking to one of their techs, this product should work for this function (even says HDTV compatible). I want other output sources too, so this will be ideal, though expensive.
Arpad @ Sep 10th 2006 1:41PM
schalliol: thanks, that would be perfect except I need usb and audio as well :~( I couldn't find any iogear kvm that has all three...
Gary M. @ Jan 11th 2007 7:24PM
Betty,
Said: "component does not carry HD signals, only HDMI or DVI can do this."
Are you sure, my HDTV does not have DVI or HDMI inputs, only Component and it get 1080i HD signals. How is this possible unless you are incorrect?
Andrei @ Jan 16th 2007 9:03AM
Is anyone familiar with the HP J1474A console switch (kvm switch) or similar CYBEX models?
I have one but no cables so I cannot check it by tester. It uses a 25 pin connector and I don't have a wiring diagram. Help me please!!
icq: 166827146 skype: andrei_kazan e-mail: shumaa2004(at)yahoo.com
Adam @ Jan 17th 2007 7:39AM
Does this mean if i just solder some 75 ohm composite cables to the correct wires on a vga cable, I can use a component out device to display on my monitor?
Andrei @ Feb 1st 2007 12:49PM
Is anyone familiar with the HP J1474A console switch (kvm switch) or similar CYBEX models?
I have one but no cables so I cannot check it by tester. It uses a 25 pin connector (like DB2 LPT on PC) and I don't have a wiring diagram. Help me please!! icq 166827146 skype andrei_kazan e-mail shumaa2004(at)yahoo.com