VGA Splitters

[Johnno]

Does anyone know whether a passive VGA splitter (D-sub Y cable) will give good results if feeding a monitor and projector (about 4m away) simultaneously? I saw a comment on one advertisers blurb to the effect that they're only good if feeding identical devices. With different devices I assume the different impedances and terminations can give rise to reflections that degrade the signal.

[Vanjast]

Does anyone know whether a passive VGA splitter (D-sub Y cable) will give good results if feeding a monitor and projector (about 4m away) simultaneously? I saw a comment on one advertisers blurb to the effect that they're only good if feeding identical devices. With different devices I assume the different impedances and terminations can give rise to reflections that degrade the signal.

 

I'd imagine your talking about analogue VGA signals, if so there will be a slight signal loss due to about 1/3 third termination overloading. As video signals are terminated with 75ohm resistors on both ends, you'd now have 3 resistors and will experience about 1/3 loss in signal strength resulting in probably sync and brightness problems. I would imagine this would be the same if there were identical monitors/projectors.

 

It's probably better to get an 'active' splitter, as this will boost the signal to normal levels on both pieces of equipment.

 

Van

[bruce]

The theoretical answer is "improperly terminated, so don't do it". The pragmatic answer is "you may well get away with it".

 

You could "suck it and see"...

 

but since active VGA splitters start at (checks catalogue) less than 15 pounds, it's perhaps not worth economising here.

[obsoperator]

I've tried it, and the most common result is decreased signal at both devices. If you're using a projector, that's an indication to me that this is unacceptable. (I'm talking about a Trade Show, Speaker Support, or even projected scenery. It's just not worth renting the equipment and then presenting a feeble image.) If you rented a sports car, would you buy 87 octane petrol for it?

[stebee]

hi,

 

If, for some reason, an active splitter is out of the question, try to get hold of a projector with a monitor output installed. this should prevent signal loss.

 

 

But as the man said for £15.....

 

Ste

[Vanjast]

Just thought of another option. you might be able to get hold of a projector/monitor that has both video-in and video-out connectors. If you can get hold of just one of these you should be able to 'daisy-chain' (connect in series) the 2 pieces of equipment.

This should resolve the issue without a splitter.

 

:D

[Johnno]

Thanks for your replies.

[Guest minisrule192]

Lindy make some good active splitters but for a four way splitter they cost about £60.

[Chris Beesley]

Lindy make some good active splitters but for a four way splitter they cost about £60.

I go with Paul on this one... there are plenty of budget splitters in the market place aimed at the PC market (ie cream coloured case not black) for £15+

[Jivemaster]

Maplin UY20W 8-1 SVGA Splitter 2 in Stock £69.99 looks an OK item without breaking the bank.

[Dave]

IMO the only splitters worth bothering with are Extron ones. Metal case and internal PSU. Having said that, I have heard that Kramer ones are OK if you don't mind an external PSU.

[Jivemaster]

The "identical devices" bit comes from the days when monitors had fixed resolutions. so the video card had to have the correct rate selected and two devices may not have had the same res so would not operate off the same vga out, but two identical devices would!

[Johnno]

Thanks all. The projector wouldn't work through 23m of cable without a booster so I got a splitter after all, on offer at £20.